The Iron Age 1926-09-30: Vol 118 Iss 14

THE IRON AGE New York, September 30, 1926 ESTABLISHED 1855 VOL. 118, Ne. 14 Steel Treaters Reach New Heights Notable Array of Technical Contributions at Chicago Convention Last Week—Exposition Surpasses All Others in Scope and Size Drake Hotel, Chicago ing at its annual meeting this year! Both in its technical and exhibition phases, the eighth annual convention and steel and machine tool exposition surpassed any previous affairs. Meeting this year at Chicago, Sept. 20 to 24, it in a measure cele- brated the eighth anniversary of its birth. In 1919, at the Seventh Regiment Armory in the same city, the first convention and ex- hibition of the American Steel Treating Society was held. This finally expanded into the present large organization, and the con- trast between the imposing achievement of this year and the one seven years ago has been most striking. This story has been told many times. \ GAIN a new record by the American Society for Steel Treat- In technical offerings this year’s program fully sustained the high standard set last year at Cleveland, Sept. 21 to 25. In attendance and keen interest, the former high water marks were met. The outstanding feature was the expansion of the exposition—exceeding by nearly 100 per cent the space engaged and the number of exhibitors a year ago. Op«n-Hearth Operating Problems VER 35 papers were presented at the 10 sessions held by the American Society for Steel Treating in the ball room of the Drake Hotel, the headquarters. With two exceptions, the sessions were devoted to mis- cellaneous topics, the program in each case being a varied one. The features were the steel-melting ses- sion and the symposium on hardness. About 60 per cent of the papers were pre-printed. In the following columns only the chief features of each session are briefly presented. A year ago the board of directors inaugurated, Chicago Municipal Pier, Which Housed the Steel and Machine Tool Exhibition at the Cleveland meeting, the plan of holding a ses- sion on steel and steel melting. It was a decided suc- cess and had the largest attendance of any meeting. This year an excellent program of four papers, under the organization and chairmanship of W. J. Priestley, Electrometallurgical Sales Corporation, New York, was presented before a large audience. Hair Cracks in Steel Rails One paper came from a British author. It was en- titled “Hair Cracks in Steel Rails,” by J. H, Whitely, South Durham Steel & Iron Co., Ltd., Malleable Works, é : ' a THE IRON AGE E. J. Lowry (at left), metallurgist Hickman, Williams & Co., Chicago, contributed a paper entitled “Desul- phurization.” His career has included a factory fore- manship at the Watertown Arsenal, research work for the United States Cartridge Co., and work as chief chemist and metallurgist for the Oliver Chilled Plow Works. His present work takes him around the coun- try consulting with clients on iron and steel manufac- turing problems A. L. Feild (at right), physicist Central Alloy Steel Corporation, Canton, Ohio, read a paper on “Solidifica- tion of Steel in the Ingot Mold.” For work on viscosity of blast furnace slag he was the recipient of the J. C. Johnson, Jr., prize of the American Institute of Min- ing and Metallurgical Engineers. He investigated the effects of zirconium in steel during a connection with the Union Carbide & Carbon Corporation September 30, 1925 Stockton-on-Tees, England. It was read by Arthur Briefly, the author contends that hair cracks are due Meyer, Alan Wood Iron & Steel Co., Philadelphia. to poorly made steel. He describes various tests he + made to detect these and similar flaws, in which he used two methods, the magnetization and treatment with iron dust in kerosene, and the effect of a reagent. Mi- croscopic examination revealed the chief features. The faulty steel contained numerous cavities filled with gas under high pressure, due in part to the rapid cooling sorbitizing. As a result, severe stresses developed near the cavities, forming local incipient cracks. It was also shown that the steel was over-oxidized, caus- ng nearly all the trouble. Hair Lines in Crankshafts F. T. Sisco, metallurgist Air Corps, McCook Field, Dayton, Ohio, asked whether the author considers hair lines dangerous. In an inspection of 100 crankshafts, they all contained hair lines, he said; and it is not going too far to say that, in the case of chrome-nickel steels, if a highly polished section such as a crankshaft is carefully examined, the defect will be found in prac- tically every case. Mr. Sisco said he had had the same experience with ball-bearing steels. The prevalence of this defect in alloy steels makes it important to know just what effect these lines may have in accelerating failure by fatigue or vibratory stresses. Crankshaft failures in service are comparatively rare, which would seem to indicate that they are not dangerous, though, on the other hand, many failures cannot be explained in any other way. Rail Steel Semi-Finished Material Contending that most rail steel is semi-finished steel, George Dornen, Gathmann Engineering Co., Bal- timore, said such steel will pass most specifications but a better-made steel would undoubtedly result in a su- perior rail. J. G. Morrow, Steel Co. of Canada, Hamil- ton, Ontario, testified that the use of hot tops had re- sulted at their plant in less cracks and defects in rails. Open-Hearth Practice A valuable contribution to open-hearth literature was a paper entitled “Basic Open-Hearth Practice,” by C. H. Herty, Jr., research associate Massachusetts In- stitute of Technology, school of chemical engineering practice, Lackawanna, N. Y. The author takes three heats of steel having three types of charges for com- parison. The first two are pig iron and scrap heats with no ore, one being charged with very heavy scrap and the other with only medium scrap. The third heat is an iron-ore heat, 20,000 Ib. of ore being charged with this scrap. The author’s comparison covers the absorption of sulphur by the scrap during melting, the oxidation of the scrap, condition of the bath one hour after the hot metal addition, elimination during the lime boil, action of fluorspar in one heat, and other stages up to re ne ee ety the final steel. The author does not discuss the effect of the process on the finished steel, preferring to limit the paper to the open-hearth furnace itself. Desulphurization and Fluxes The results of an investigation of about 176 heats of steel treated with soda ash, fluorspar and other fluxes are contained in a paper, “Desulphurization,” by E. J. Lowry, metallurgist Hickman, Williams & Co., Chicago. The paper is an assemblage of his own results and those of other workers. One object was to find out the possibilities of soda ash as a substitute for fluor- spar and also the desulphurizing effect of these fluxes- He is of the opinion that fluxes have “def “te lines which divide them into classes which producee€1) prop- er slags, (2) proper slags combined with an efficient desulphurization and (3) improper slags. He believes that a secondary function of the three factors, slags, fluxes and desulphurizers is temperature which plays a most important part, and he sets forth by means of tables and a resumé exactly what work was performed and what fluxes were used. Some exceptions were taken to some of the author's statements by C. H. Herty, Jr., who contended that one cannot study fluxes without taking into account the entire composition of the slag. In his experience, the use of large amounts of soda ash did not reduce the sulphur in the steel. In adding it to the blast- furnace ladle, soda ash does not act as a desulphurizer when the manganese is high. He also stated that when slags are high in iron oxide, they are thin and active. Solidification of Steel in the Ingot Treating mathematically the linear rate of solidifi- cation of steel and the location and shape of the shrink- age cavity, with certain simplifying assumptions, Alex- ander L. Feild, physicist Central Alloy Steel Corpora- tion, Canton, Ohio, made an important contribution to the literature on the steel ingot. His paper was enti- tled “Solidification of Steel in the Ingot Mold.” In the case of steel poured at its melting temperature, the maximum rate of solidification is shown to be inversely proportional to the square root of the elapsed time, measured from the moment of contact between liquid steel and mold wall and also the distance through which solidification has progressed is directly propor- tional to the square root of the elapsed time. The effect or degree of super-heat above the melting tem- perature and of mold-wall thickness upon solidification rate are discussed. Finally, equations defining the sur- face of the shrinkage cavity are derived for mold cham- bers of uniform cross-section, ordinary taper and in- verted taper, and the important effect of pouring rate and taper upon pipe formation emphasized. Emil Gathmann, president Gathmann Engineering Co., Baltimore, discussed some of Mr. Feild’s equations and said that the author’s mathematical treatment of a very complex subject is a valuable addition to the literature of the art. THE IRON AGE AeA ny et Ramanan ee RN eRe) een I Dr. D. J. McAdam, Jr. (at left), member of the United States Naval Engineering Experiment Station, Annap- olis, has specialized in the invention and improvement of machines for impact and endurance tests of metals. His contribution to last week's meeting was a paper on the influence of inclusions on the fatigue strength of steel Howard M. German (at right), metallurgist with the Universal Steel Co., Bridgeville, Pa., is the author of a paper on “Standardizing of the Brinell Hardness Tests.” About 15 years ago he was professor and head of the department of metallurgy at the South Dakota School of Mines, and later was metallurgist for about 10 years with Henry Disston & Sons, Inc., Philadelphia Considerations of the Hardness Question EVERAL papers were presented at a symposium conducted by the hardness testing committee of the society. Standardizing the Brinell Test A paper on the “Standardizing of the Brinell Hard- ness Test” was presented by H. M. German, Universal Steel Co., Bridgeville, Pa. He said that the Brinell test has its limitations in that the only metal that can be tested is that which will stand permanent deforma- tion and that which is of sufficient thickness and hard- ness so that a bulge will not be caused on the opposite side. The standard load when testing comparatively hard steel is 3000 kg. and in order to obtain accurate readings the load must not be subject to variations. He pointed out defects of various types of machines due to the fact that gages and springs could not re- tain their accuracy. He claimed that only one of the various devices for applying pressure that will give an accurate and con- stant pressure is a type of weight and lever machine in which the load is obtained by weights and compound levers and applied to a plunger containing the ball which is pressed into the piece to be tested. Errors in testing are due to the fact that the applied load is not constant, owing to the design and manipulation of the machine and to the fact that the rate of application of the pressure and the time the full load is applied are not fixed, but are optional with the operator. The author described a new design of Brinell machine of the weights and levers type operated by a cam through a motor with push button control, which, he said, would overcome the defects found in other types of machines, as it would remove the personal factor, assure fixed rate of pressure of application, fixed time of pressure application and constant application of the load. This paper was discussed by Herman H. Holz, test- ing engineer, New York, who said that the Hultgren Brinell balls, which had been mentioned by Mr. German, are now in extensive use and are giving good service, their development representing a distinct advance in hardness testing. The etching of Brinell balls to pro- duce clearer outlines is an American development. Etched balls have been criticized on the ground that a greater load is required to force an etched ball into a metallic surface than would be necessary with a polished ball. However, he had made many tests with etched and polished balls and had been unable to detect the slightest difference due to such theoretical variable friction. The general tendency, he said, is toward the use of hydraulic machines for both hardness and tensile testing. He did not favor the use of automatic ma- chines except for large production work. If power machines are used he favored having them operated with motor driven pumps. In conclusion, Mr. Germaft said that anything that can be done to eliminate the personal element will help to standardize Brinell tests. Dr. William M. Guertler, Charlottenburg, Germany, gave a talk on the hardness of metals and Prof. S. R. Williams, Amherst College, Amherst, Mass., discussed in two papers some of the factors that enter into the problems of hardness. One of these papers was on the correlation of magnetic properties with mechanical hardness in cold worked metals and the other on hard- ness testing of steel balls by magnetic methods. Toughness of High-Speed Steel The subject of toughness of high-speed steel was discussed by Robert K. Barry, Barry Co., Muscatine, Iowa, the data being supplemental to a paper pre- viously presented before the society by Mr. Barry. He stated that in his previous paper it had been shown that 18 per cent tungsten high-speed steel previously hardened developed maximum hardness and usable toughness after a 1100-deg. draw. It had been stated that when making impact tests the highest values of greatest strength may be expected after an 890-deg. draw in the range where austenite is being rapidly converted. Mr. Barry had been asked to prepare several sets of treated test specimens as near alike in composition, physical condition and treatment as possible to further compare impact and deflection test values as governed by various drawing temperatures. The tests were made with cold-drawn high-speed drill rod. The sets tested by impact showed that the highest impact value was ob- tained after drawing to 900 deg. A drawing at 650 deg. was productive of inferior hardness and the lowest value. This was the point of lowest hardness for a draw up to 1100 deg. The test for deflections showed that up to 1100-deg. draw, the highest deflection was obtained when drawing to 1100 deg., the point of maxi- mum hardness. He said it is significant that more force was required to break the pieces at 1110 deg. than to break them when drawn at any lower temperature. This clearly indi- cated the desirability of a 1100-deg. draw when maxi- mum hardness, deflection, strength and fiber stress are required. Low deflection followed an 800-deg. draw. The 900-deg. draw produced values slightly superior to those resulting from 800-deg. draw. However, it is apparent that both draws are inferior unless the results determined by impact testing are accepted. The speaker remarked that the bundle method of conducting tests of this nature has much in its favor and that the deflection or slow bend method of testing hard steel indicates a superior sensitivity. If in a high- speed tool toughness is most essential, the hardening temperature must be considered or the manner of treat- ing to harden, for attempts to toughen by severe draw- ing may prove disappointing. . . j THE IRON AGE W. J. Merten (at left) discussed “Wear Resistance of Carburized Steel Versus High Manganese Steel.” He is metallurgical engineer connected with the Westing- house Electric & Mfg. Co. Formerly he was metat- lurgical engineer with the Union Switch & Signal Co., Swissvale, Pa., and the Twin City Forge & Foundry Co., Stillwater, Minn., and was assistant manufactur- ing superintendent Ohio Brass Co., Mansfield, Ohio John M. Lessells (at right), metallurgist, Westing- house Electric & Mfg. Co., presented a study of the fatigue strength, or hardness, and the tensile strength of hard steels. He was born in Scotland and was em- ployed on the staff of the British Air Board as inspec- tor during the war. Among various technical contri- butions was one for which he was awarded a prize by the Institution of Mechanical Engineers nee venaennny! September 30, 1926 OeseieneLONNNRDNE ET ONNERARDOAHOOONLEN OUND ORE FREE DETAEBEFD LESH EEK G Cus: Discuss Fatigue Failure of Metals = of three papers was given on this subject i of the fatigue failure of metals. F. F. Lucas, Bell Telephone Laboratories, New York, presented a story of the path of fatigue fracture in ingot iron, illustrated by a series of excellent photomicrographs, taken at very high magnification. Non-metallic inclu- sions mark the path like stepping stones; a thin dis- turbed region appears to exist on either side of the rack. Carbide inclusions do not appear to be a source of weakness; neither do grain boundaries, nor do crys- tallographic planes govern the location of the break. Another indication of the great influence of inclu- sions on the fatigue strength of steel was contained in a paper by Dr. D. J. McAdam, of the U. S. Naval Engineering Experiment Station, Annapolis, Md. In a continuation of the work reported last spring to the American Society for Testing Materials, he shows that the fatigue resistance of steels, as determined by the rotating beam test, is greatly lowered by merely play- ing cold water on the specimen during test. Rapid localized corrosion starts in at the non-metallic inclu- sions, which corrosion causes incipient cracks to start in a very short time, one of these cracks eventually extending through the sample and causing unexpected- ly early failure. To quote an extreme instance, a 5 per cent nickel steel having a tensile strength of 125,000 lb. per sq. in., a Charpy impact value of 38, and a normal endurance limit of 69,000 Ib. per sq. in. is able to withstand onl) 25,000 lb. per sq. in. alternating stress when in a moist condition. H. Styri, S. K. F. Laboratories, Philadelphia, comment, noted that the cleanliness of the steel is known to have a marked influence on the performance of ball bearings. Over half the balls and races exam- ined after fatigue failure show tiny cracks associated with slag. It is also known that corrosion, due to hu- midity or to unsuitable lubricant will cause premature breakdown of ball races. Another speaker said that a high tungsten die for bolt-heading gives better performance than a high chromium die when running without coolant; but the relative life was reversed when the die was cooled with a stream of water—a fact which might be taken to in- dicate a superior corrosion fatigue limit of the chro- mium steel. J. M. Lessells, metallurgist of the Westinghouse Electric & Mfg. Co., Pittsburgh, studied the fatigue strength, or the hardness, and the tensile strength of certain hard steels, and found the relation to be nearly constant if the quenced steels were adequately tem- pered. He thinks that variation from the straight-line relation is due to internal strains induced by the hard- ening, and by experimentation discovers such residual stresses of the order of 110,000 lb. per sq. in. in the freshly quenced metal. Wearing Properties of Certain Steels WO papers dealing with the wear resistance of some special steels created considerable interest. An ab- stract of each, with some of the discussion, follows: Carburized versus Manganese Steel Experiments conducted to determine the compara- tive wear resistance of 14 per cent manganese steel and case-hardened steel were the subject of a paper on “Wear Resistance of Carburized Steel vs. High Manganese Steel,” by W. J. Merten, Westinghouse Elec- tric & Mfg. Co., East Pittsburgh, Pa. The experiments were made to ascertain the relative wear-resisting qualities of these steels used in flexible spring seats and pads. A quill drive spring unit assembly was connected to a belt driven crank shaft and clamped between an adjustable stationary upright member, to which were welded the wearing pads, providing appa- ratus for tests that closely resembled actual service conditions. Direct comparisons of wearing qualities were made by using one seat and pad of carburized plain carbon steel, and the other seat and pad of cast manganese steel. Tables were given showing the re- sults of -five tests. The author said that a summary of the results ob- tained not only confirms what has been known about plastic flow of 14 per cent manganese steel when sub- jected to heavy pressure when in a sliding motion, but it also establishes the fact that even under an appar- ently more favorable structural condition (martensitic) it compares unfavorably with case-hardened steel. However, one factor in favor of manganese steel is that its entire sectional dimension gives practically the same value of wear resistance, while the depth of 4 wear resistance case in case-hardened steel is rarely more than 3/32 to % in. He pointed out that favor- able results from case-hardened steels obviously de- pend upon the care exercised in carbonizing and heat treating. John Howe Hall, metallurgical engineer, Taylor- Wharton Iron & Steel Co., High Bridge, N. J., came to the defense of manganese steel in a prepared dis- cussion which, in his absence, was read by F. F. Lucas, Bell Telephone Laboratories, New York. Mr. Hall said that the conclusion might be drawn from Mr. Merton’s paper that, in case of metal-to-metal abrasive, a cas¢- hardened article is better than one of 12 per cent steel. He declared that Mr. Merton’s conclusions held good only for such services as characterized by his par- ticular test. Twelve per cent manganese steel in the heat-treated condition is comparatively soft and does THE IRON AGE Dr. Kotaro Honda (left) is joint author with Keizo Iwase of a paper on “Transformation of Retained Aus- tensite into Martensite by Stress." Dr. Honda is a member of the Imperial Academy of Japan and direc- tor of the Research Institute for lron, Steel and Other Metals of Japan. He was awarded the Bessemer gold medal by the Iron and Steel Institute of Great Britain and is a prolific author on metallurgical subjects and the recipient of numerous international honors H. K. Herachman (right) is joint author with H. J. French, both of the Bureau of Standards, of a paper on “Wear of Steels with Particular Reference to Plug Gages.” Besides applying himself to research, Mr Herschman has been admitted to the bar of the Dis- trict of Columbia 911 not resist wear unless the wear is accompanied by severe pressure or pounding. Under severe cold work- ing, the hardness of the surface of manganese increases to about 500 Brinell, and, because of this hardness, this steel successfully resists wear accompanied by heavy pressure. This change in surface hardness con- tinues as the manganese steel article wears down, the metal hardening as rapidly as exposed to wear, so that the rate of wear is uniform. This change in hardness is due, he said, to an alteration of the physical state of the metal. He and Mr. Lucas had explored the metallographic change involved, the exact value of which they were not yet ready to make public. Mr. Hall declared that in such service as metal-to-metal gear drives, where the loads are very heavy, man- ganese steel castings harden rapidly on the surface and will outwear any other material from 5 to 10 times. Gages and the Wear of Steels “Wear of Steels with Particular Reference to Plug Gages” was the subject of a paper by H. J. French and H. K. Herschman, Bureau of Standards, Washing- ton, read by the former, that brought out considerable discussion. A new plug gage wear testing was de- scribed, and there were outlined the results of tests with the use of this machine with heat treated steel gages and chromium plated gages. Both metal-to- metal wear tests and abrasive wear tests were made. Under wet sliding friction, with the gages in contact with file-hard 1.06 per cent carbon steel rings, the chromium plated gages showed an exceedingly high resistance to wear in comparison with file-hard or file- soft carbon and special tool steels. File-soft gages were more resistant to wear than file-hard gages made from the same steels. The chromium plated gages did not show the marked superiority in wear resistance in the abrasive wear tests that they did in the metal- to-metal wear test, their life being more nearly the same as gféges made from quenched and tempered high- speed tool steel, which in turn was more resistant to wear than file-hard or file-soft high carbon, chromium ball race and so-called oil hardening now deforming tool steels. In the abrasive wear tests, and to a lesser de- gree in the metal-to-metal wear tests, the soft gages were less than the file-hard high carbon steel rings in which they were sliding. B. H. Blood, Hartford, Conn., in a written discus- Ob SENEERNER EEN LAO: «beNETEAN EONS van ony emENEDS LONE ET seeeee en 8 OR ee ARE TET sion of the paper, declared that the authors were doing valuable work, and urged the necessity of cooperation on the part of gage users if laboratory results are to be checked against actual performance. It is appar- ent, he said, that no one steel and no one heat treat- ment is likely to be found best for all conditions. He suggested that for the abrasive wear tests shop condi- tions might be more closely simulated by using in the place of lard and emery a water solution such as is generally employed in grinding operations, carrying the usual amount of abrasive and steel chip. He alae suggested that, with plug gages as the starting point of this investigation, similar work on thread gages might be of more importance commertially. In view of the results shown, the wisdom of requiring gages to be file hard may be further questioned, though this depends on the metal to be gaged. He believed it would be advisable to use one steel or temper for work- ing gages and another for final inspection when the work has been cleaned. L. A. Dause, Cadillac Motor Car Co., Detroit, stated that tests at the Cadillac plant showed that those run by repeated applications of the same test surfaces to the gage do not wear the gage nearly as rapidly as do applications of new surfaces to the gage, the increased wear to the latter being due to the roughness of the grinding wheel. Their tests positively demonstrated the superiority of file-hard gages over file-soft ones. With Stellite gages “loading” is seldom encountered. Chromium plated gages also have a marked resistance to loading. A. H. d’Arcambal, Pratt & Whitney Co., said that the wear test machine should give reliable results, but that the results obtained do not check with gages in actual service. Plug gages made of high-carbon tool steel and incorrectly hardened by oil quenching would give very little service under working conditions, as they would not take as high a polish as file-hard gages. Gage makers, he said, are primarily interested in the comparative wearing qualities of file-hard gages with gages correctly hardened but drawn to 425 to 440 deg. Fahr. instead of the 360 deg. Fahr. draw. Mr. French, in concluding the discussion, said that a marked superiority was found in chromium-plated gages when properly lapped, but the results were poor when the gages were not lapped. He pointed out that he was not recommending file-soft gages at this time, but only showing the results of tests. English Practice on High-Speed Steel F. C. A. H. Lantsberry, William Jessop & Sons, Sheffield, England, presented a lengthy paper on “High- Speed Steel,” which attracted attention as probably indicating good metallurgical practice in England. Crucible steel is preferred by the writer to electric steel, even though it may cost 50 per cent more, be- cause the former starts with purer raw materials and the latter is hard to control. Judging from the Ameri- can comment, the repute of electric steel is steadily growing; large tool manufacturers now find it easier to get uniform and satisfactory tool steel from the electric furnace than the crucible melter. Steel makers also insist that it is good metallurgy to do some of the refining in the steel making operation rather than ed FBI ES os Bt ee S32 ok 2 THE IRON AGE seeeeenoeesneenanseoeseeneneernnespennesansareneuscereawennen rym senensnteneoneeeenenenesnet P. G. MeVetty (at left), mechanical engineer, Westing- house Electric & Mfg. Co., together with N. D. Mochel, presented a paper on the tensile properties of stain- less iron and other alloys at elevated temperatures. For a time Mr. MeVetty was in charge of research for the Leather Belting Exchange and later an assistant superintendent of the south side works of the Jones & Laughlin Steel Corporation Victor E. Hillman (at right), director of chemical re- search, and E. D. Clark, metallurgist Crompton & Knowles Loom Works, Worcester, Mass., were authors of a paper entitled “Cyanide Brittleness.” During the war Mr. Hillman was affiliated with the Savage Arms Corporation as chief of the metallurgical staff September 30, 1926 to expect to do it all in preliminary smelting. Accepted English analyses fellow: “Super” 14 Per Cent 18 Per Cent Steels Type Type ——_——" Tun 2.0 to 14.0 16.0 to 18.0 17.9 19.0 Carbor 1.60to 0.65 0.60 to 0.65 0.71 0.77 Chromiu : 3.5 3.8 3.8 Vanadiur 0 20 { { 0.20to 0.30 1.3 0.6 Molybdenun 0.7 Cobalt ‘ 5.4 Mr. Lantsberry noted that the 14 per cent tung- sten steel ingots are 20 per cent cheaper than the 18 per cent, and tools made from them are well able to resist considerable stress while cutting. Therefore these steels make extellent twist drills, reamers and dies. (It may be remarked that the first two steels are quite low in vanadium, as compared to American steels, and also about 10 points low in carbon.) HNEVOCEEDERODEULUEDOEODOOEONSEDEUEEDUREETONEA DCEO OUOROUERRDOEERENTERRERE ENERO TEREDDORD OH OEROVORROHELLERDN ON HERT OFT tr rir itsce/eianeR In the author’s opinion there is little chance of in- creasing the speed of present steels—indeed, he feels that this is hardly necessary, since cutting speeds of 150 ft. per min. are common in mild steel. Red hard- ness is now satisfactorily maintained up to 700 deg. C., and this is as hot as anyone would want to work a tool. Something may be gained by increasing the in- trinsic hardness by getting a more uniform distribution of the carbide in the steel. Several speakers, in comment, were of the opinion that a carbon content of 0.70 to 0.75 per cent would give a marked increase in cutting ability. A little more tungsten and a hardening temperature about 200 deg. Fahr. higher than that recommended by Mr. Lants- berry would also give a better red hardness without undue grain growth. Hardening Light Metal Alloys A LLOYS of the duralumin type are rather difficult to work and their commercial developments have been somewhat retarded by this characteristic, said Robert S. Archer, Aluminum Co. of America, Cleveland, in a paper entitled “The Hardening of Metals by Dispersed Constituents Precipitated from Solid Solutions.” In view of the potentially great utilities of strong alumi- num alloys, the Aluminum Co. of America, several years ago, undertook the production of new alloys. This work resulted in the production of two types of aluminum alloy of the strong alloy class having distinctly im- proved fabricating qualities. One of the new types referred to consists chiefly of aluminum and copper. ‘he binary aluminum-copper alloys, especially when made from metal of ordinary purity, show very little age hardening at room temperature after the solution heat treatment. They are, however, susceptible to marked hardening by reheating at 212 to 347 deg. Fahr. (100 to 175 deg. C.). The other type of alloy referred to consists chiefly of aluminum, magnesium and silicon. These alloys show distinct age hardening at room temperature after the solution heat treatment. The strength retained un- der these conditions, however, is not very great, usually well under 40,000 lb. per sq. in. In the laboratories of the Aluminum company it was found that the hardness. strength and elastic ratio of these alloys could be fur- ther increased to a marked extent by an artificial aging at about 212 to 347 deg. Fahr. By this means it was possible to obtain a tensile strength as high as 54,000 lb. per sq. in., a Brinell hardness of 120 and a yield point of about 40,000 lb. per sq. in. In summarizing, Mr. Archer said that metals mav be effectively hardened by highly disbursed particles within the grains, such as may be formed by super- saturated solid solutions. A typical process of harden- ing by this means consists in a solution heat treatment at a relatively high temperature followed by rapid cool- 4 ing in a region of super-saturation, then by precipita- tion treatment or aging to permit the formation of a very fine precipitate. The precipitate tends to grow to a critical particle size conducive to maximum hardness, beyond which the hardness decreases. Mr. Archer’s paper is an elaboration of others which he and Dr. Zay Jeffries have presented in the recent past. The new paper, however, brings out particular- ly some recent developments in connection with mag- nesium and its alloys. Interesting discussions were offered in writing by Dr. Paul D. Merica, director of research, International Nickel Co., New York; by R. S. Dean, Western Electric Co., Chicago; by O. W. Ellis, research laboratory, West- inghouse Electric & Mfg. Co., East Pittsburgh, and H. C. Knerr, consulting metallurgical engineer, Phila- delphia. Space permits only an allusion to these. Doctor Merica said that there is still controversy concerning the exact mechanism of the hardening phe- nomenon in some cases. One stumbling block facing the precipitation theory of the hardening of duralumin is the established decrease of conductivity during ordi- nary temperature aging of it. Mr. Archer makes some quite pertinent comments on this difficulty and raises the question whether we have a right to expect an in- crease of conductivity with decreasing solid solution concentration under all circumstances. But there are other factors which play some part in the conductivity of an aged sample of duralumin. Elastic strain affects electrical conductivity in the tensional axis. It ap- pears most difficult to estimate the probable value, dis- tribution or effect of these internal stresses, but it seems most probable that they exist, said Doctor Merica in conclusion, adding that he is compelled to join with Mr. Archer is questioning the absolute solid- ity of the conductivity evidence against the precipita- tion theory. September 30, 1926 THE IRON AGE 913 r Francis J. Curran (at left), with Prof. C. G. Priester, University of Minnesota, offered a discussion of the mechanical and machining properties of an annealed cast iron. Mr. Curran was engaged as metallurgical engineer for two years for the Arrow Head Steel Products Co., Minneapolis, and later for the Associated Chemists, Minneapolis Dr. Vsevolod Nicholas Krivobok (at right), bureau of metallurgical research, Carnegie Institute of Technol- ogy, Pittsburgh, is the author of a contribution en- titled “Dendridic Crystallization and Grain Formation in Steels.” The Government of Russia sent him to the United States as a member of an Artillery Commission in 1915-1917. He went back to Russia in 1919 as engi- neer in the metallurgical department, Ministry of Rail- ways, Government of South Russia. In 1920 he returned to the United States REI S10 FONT POREREDORUENERNL DERE DUNN OELONELOORALAD NAG TENDOLELT DONOONELLI/INNCEIELOEEODESURLEDESD DEREUUEE!® RVHEDL EN Bs UPREEY LEHERADEREQBEDEAUSBREFEY ERI Oe \eemR AE NERY OL ou TREE OCLUBERL EOS Saou pEEE RE Per evdnees pENORERRAE On es can HeREORa ONT Aer H¥e! Ors OF DENaRONEMREEELESEaE: s6) HE resent Other Papers of Notable Importance Some of the other papers of commanding interes ‘ presented at various sessions of the meeting of American Society for Steel Treating are reviewed briefly in the following: Stainless Iron at High Temperatures AT that attracted more than the usual amount of interest was one on “The Tensile Properties of Stainless Iron and Other Alloys at Elevated Tempera- tures.” This was prepared by P. G. McVetty and N. D. Mochel, mechanical engineer and metallurgical engineer respectively, Westinghouse Electric & Mfg. Co., and was presented by the former. The tests covered in the paper were made with me- dium carbon steel, 5 per cent nickel steel, stainless iron in the form of forged and rolled bars, cast manganese bronze, brass and Monel metal. Results that were ob- tained in short time tensile tests at high temperatures were shown on charts. In these the main tensile properties of the nine materials were compared in the entire range of temperature studied. The data in- dicated that annealed stainless iron of the grade ex- amined has good tensile properties up to 752 deg. Fahr. without evidence of brittleness. Between 732 and 932 deg. the strength decreases more rapidly and the ductility increases. Hot rolled Monel metal up to 752 deg. shows good tensile properties, but it becomes brittle at 932 degrees. The authors pointed out that the short time tensile tests cannot indicate the service conditions upon mate- rials exposed to high temperatures. In this connection they referred to some of the long time tensile tests they had made. Results of long time tests of stainless iron were shown in tables. The tests showed that annealed stainless iron does not deteriorate as a result of ex- posure to stress and temperature for periods up to one month. Similar tests of heat-treated stainless iron showed that the ultimate strength and ductility are not seriously affected by such exposure for periods up to four and one-half months. The authors found that the Martens mirror type ex- tensometer gave good results in the measurement of extensions in short-time tensile tests, but it was al- most impossible to prevent disturbances of this instru- ment when used for long-time tests. Consequently the Martens telescope was replaced by a specially de- signed projection apparatus with which it is possible to estimate millionths of an inch. H. R. L. Templin, Aluminum Co. of America, in dis- cussing the paper, said that tests have recently been made of aluminum at high temperatures and that a paper is being prepared on this subject. He did not find test specimens with threaded ends satisfactory for high temperature work and used a different form of test piece. He had made short-time tests of various alloys to show their tensile properties at high tempera- tures, but had not attempted long-time tests. H. J. French emphasized the great practical importance of “creep” in its relation to tensile tests. He also pointed out that the load-carrying ability of steel at different temperatures is a matter of great interest. In closing the discussion, Mr. MeVetty said that be- cause of the variation in test bars he had adopted a system of magnetic testing of test bars and those that show much variation are discarded. The proportional limit shown in short-time tests, he said, is good evi- dence of the maximum load-carrying capacity in ser- vice. In making tests he pressed the thermocouple against the test piece, which he regarded as preferable to pitting the thermocouple in the test piece. “The Decomposition of the Austenitic Structure of Steel” was discussed in a paper prepared by Dr. O. E. Harder and Dr. R. I. Dowdell, University of Minnesota, which was presented by the latter. The authors had handled this subject in six sections, but only the last section was preprinted. In this part of the paper the authors used the results of their investigations as the basis of a proposed theory for the hardening and tem- pering of steel. Brittleness Due to Cyanide “Cyanide Brittleness” was discussed in an interest- ing paper by V. E. Hillman, director of chemical re- search, and E. D. Clark, metallurgist, the Crompton & Knowles Loom Co., Worcester, Mass., which was read by Mr. Hillman. Low carbon steel cyanided, he said, is extremely brittle if the core is intact, but when the core is removed it shows extreme ductility. Results of various tests were given and graphs and photographs shown. Six standard test specimens were immersed in a cyanide bath at 1500 Jeg. Fahr. for 15 min. and then quenched in water. This was repeated at 30, 45 and 60-min. intervals. These showed that the brittle- ness of the metal becomes more pronounced as the period of cyaniding increases. The percentage reduc- tion of area decreased from 62 to 0 per cent. A 30-min. cyanide treatment, which conforms to shop practice, resulted in a reduction of area of only 4 per cent. The tensile strength, which is an index of brittleness, in- creased as the period of immersion was prolonged. Similar results, to a less degree, were obtained from oil quenching. Other test bars were cyanided, the case was removed by turning the specimens in a lathe, then they were reheated and quenched. These showed by virtually no change in the percentage reduction and in the tensile strength that no brittleness was in evi- dence. The case of other specimens after cyaniding was removed by grinding, but ductility was still in evi- dence. The opinion was advanced that the apparent brit- tleness of the core with the case intact might be due to the strained condition of the metal caused by quenching. Se re at eens ome emp! ATE SL eran ; ; I ale et. Brat ; ph or 9 914 THE IRON AGE Consequently specimens were cyanided, quenched and reheated. Notwithstanding the drawing treatment, brittleness was still in evidence. The data indicated that a piece of steel after cyaniding and quenching in water will break readily when subjected to stress, but when the case is removed the same piece possesses ductility. ‘Therefore the brittleness in the core is ap- parent, not real. Among the conclusions were that breakage of yanided products is developed by the extreme brittle- ness of the case which causes an incipient crack when sudden shock or a steady load are applied, and when inchoate fracture is once effected, breakage is rapidly transmitted through the core because the crystals of the hard surface and tough interior are mutually in- volved or intertwined. In briefly discussing the paper Stanley P. Rockwell, Stanley P. Rockwell Co., Hartford, Conn., stated that he regretted that impact tests were not made and that an analysis was not made for nitrogen. He thought re was no doubt that cyanided steel increases in rogen and that nitrogen is a harmful element when troduced in quantity. C. A. Lampard, Yale & Towne Mfg. Co., Stamford, onn., said that he had had experience in case harden- ing high phosphorus steel, but he had to come to low phosphorus steel, running 0.15 per cent in carbon, to eliminate brittleness. Mr. Hillman replied that he got rid of much of the hardness by quenching in oil. Valleable Iron Three papers of a theoretical nature were pre- ented by H. A. Schwartz and H. H. Johnson of the National Malleable & Steel Castings Co., Cleveland, and by Prof. H. P. Evans and Anson Hayes of Iowa State Sapenensees ree ee messeenmemrswenservveeHNeT reesnens aves pens rensdts Hee pees eneemenenenenenaonaene SUUEMENTEOCG. VRAUERIMEN ENDS DORA EALDITARATEN O40 008GSEUSUOEEI//OERUDERERURDADLDSEDI ERS OSDEDEREDABEDORDLELGETOOADIONL ONG OT ISOREDUNTRASDERERPEDHNGT I VGEHITY F44y rou enEEOESE UNEROTTENN TENT? September 30, 192+ College. These had to do with the transformations the stable and meta-stable iron-carbon diagrams, es). cially as affected by the presence of a third element lik. nickel, silicon or oxygen. The mechanism of the change from white iron malleable iron is not well understood, and the attentio: now being given to it by physical chemists of marke: ability will undoubtedly bring results which can late: be utilized to advantage by the malleable industry. Heat Treatment Furnaces Two very efficient furnaces of the continuous type were described by W. A. Timm, Western Electric Co. and by E. R. McPherson, Packard Motor Car Co. Th former has installed a double tunnel car bottom furnace for box annealing small iron parts for electromagnets The material progresses through the furnace in op- posite directions on the two sides; the pre-heating zon in one is therefore alongside the cooling zone in the other tunnel. At the middle of the furnace is a com- mon chamber for the soaking heat. Heat is supplied by banks of electric resistors suitably placed in the walls and roof of the furnace, and in the car bottoms to which current is brought by a third rail contact; 160 kw. of power are required. It requires 18 hr. for a car to pass through the furnace. The furnace contains six cars at all times, each of which carries 1500 lb. of work and an equal weight of box. The installation thus has a capacity of 8 tons per day. A year’s operatior shows that it produces better work at a lower price and with far better working condition than the 11 oil- fired furnaces which it replaced. The Packard installation comprises two continuous furnaces, 25 ft. long, 4 ft. wide, for carburizing gears and pinion shafts. Each furnace is equipped with four High Lights at the Chicago Convention YPLENDID array of technical pa- A) pers bringing up to date the latest developments in steel treating and re- lated subjects. A steel and machine tool exposition excelling in comprehensiveness and size any previous ones. The display of machine tools made up nearly 50 per cent of the total space and was nearly double that of a year ago. The attendance at the technical ses- sions and particularly at the exposition. was large. All records at the latter were greatly exceeded. Several noted German, French and British scientists were present. Plant visitations were a feature of week's program. These were sched uled for morning and afternoon of each of the five days and included 13 sepa rate trips to plants of 15 or more companies. Chicago offers special ad- vantages in its steel plants, foundries and heat-treating departments of vari ous manufactories With T. V Purcell, Peoples Gas Light & Coke Co., Chicago, as general chairman and A. G. Henry as general secretary of the Chicago convention committee, every phase passed off smoothly and satisfactorily. The Chi- cago chapter and its co-workers de- serve the highest praise for the com- plete arrangements made for the larg- est convention and exhibition of its kind ever held. Of a total of 4000 members of the society, 2025 were registered. No sooner have the doors closed on the 1926 convention than preparations are set in motion for the one in 1927. This is scheduled already for the week of Sept. 19 at Detroit with the expo- sition located at Convention Hall, where 100,000 sq. ft. will be available The society’s secretary, W. H Eisenman, after weeks of arduous work, has been granted a leave of ab- RH 0800 4F THEOL ERPTNONR CTC EMINNOR NEL ETIEN HHL!) HH NN NOL I INAUEALUDOEREN (ILI ODNSD) OLPLEWERINNE PHEERERERRREDSERE UH ENESIGE 614) Geet Oy pee sence of about six weeks He will sail for Europe on Oct. 9, visiting En- giand, Germany, France and other countries, where he expects to meet some of the leading metallurgists in various industrial centers Attendance at the steel and ma- chine tool exposition exceeded the ex- pectations of the most optimistic pro- moter. The total attendance is placed at 80,000. This was particularly true on the last evening, when the crowd was very large. The quality of the attendance this year was a matter of comment—better than on most former occasions A central figure at several of the technical sessions was the distin- guished German metallurgist, Dr. Wil- liam M. Guertler Brought over by the society to deliver the first E. D Campbell memorial lecture, he pre- sented two other important addresses, one on light metal alloys and one on the hardness of metals at the Sympo- sium on hardness Among other foreign visitors inter- ested in the way American metallur- gists conduct conventions was a French leader of industry, M. Pierre Aubert, and a British educational leader, T. Henry Turner M. Aubert eran ras coe is of the firm of Aubert & Duval, Paris, and is in this country in connection with the granting of an agency to the Ludlum Steel Co. for licensing the use of the new nitrating surface hardening proc- ess developed by Fried. Krupp & Co Mr. Turner is a lecturer in metallurgy at the University of Birmingham, Bir- mingham, England, and the son of the famous Professor Turner of the same institution. The latter is to rece'v« one of the honorary medals at the foundry convention in Detroit next week and his son will accept it for him. With Judge E. H. Gary and Charles M. Schwab added to the list of hono- rary members, the total is now eight They include also Sir Robert Hadfield, London, England; Dr. Albert Sauveur, Cambridge, Mass.;: Dr. John A. Math- ews, Crucible Steel Co. of America, New York; Henri Le Chatelier, Paris, France; Kotaro Honda, Sendai, Japan, and Charles F. Brush, Cleveland. An interesting side-light on the his- tory of the exposition movement was the presence here and there of ban- ners “Pioneer Exhibitor Chicago 1919.” It develops that nearly half of the original 65 to 70 exhibitors at that pioneer attempt in September, 1919, were represented among the 350 to 360 this year. ee 4 September 30, 1926 THE IRON AGE 915 A. F. BOISSONEAU nemennenasaewene sas eagUeeeneesse seSORGSCOERGGOUIED YS HOTITAREYTEGHE" HEDETS Hv PNHC Pas innenee oil burners at the end where the charge enters. Products of combustion circulate through the second half of the furnace, maintaining it at a temperature guaranteed to be uniform within 10 deg. Fahr. Waste gases then pass through a recuperator, heating the air used for combustion. Eac