The Iron Age 1939-12-07: Vol 144 Iss 23

FRITZ FRANK President J. H. VAN DEVENTER Editor c. E. WRIGHT J. A. ROWAN A. l. FINDLEY Managing Editor News Editor Editor Emeritus Machinery Editor Art Editor Metallurgical Aditor Associate Editors Washington Editor Resident District Editors Ta Pitteburgh Chicago Cleveland Detroit Editorial Correspondents London, Bngland Cincinnaté FRAZAR Boston Hamburg, Germany MEYER CHARLES Post Milwaukee San Francisco SANDERSON ASA JR. Toronto, Ontario Birmingham ALLISON Roy EpMONDs Newark, N. J. St. Lowtes TURNER, DECEMBER 1939 Owned and Published Tellurium, Selenium and Sulphur Copper Alloys........ Gas Content vs. Steel Behavior CHILTON (Incorporated) Porcelain Enameled Factory Building Philadelphia, Pa., U.S.A. New York, Y., U.S.A. Control Sulphur Basic Open Hearth OFFICERS AND DIRECTORS MUSSELMAN, President Peirce Lewis, 7310 Woodward Ave., Detroit Index to Advertisers 184 C. H. Ober. 239 W. 39th St., New York W. B. Robinson 92 Pp, ¢ P Warren, Box 81, Hartford, Conn. Don y. Harner, 1595 Pacific Avenue, Long Copyright 1939 by Chilton Company (Iinc.) Seach, Cal t's New Heat Treating Apparatus FRITZ J. FRANK, Executive Vice-President Wha g PP FREDERIC C. STEVENS, Vice-President JOSEPH HILDRETH, Vice-President Statistics Metal Working Activity GEORGE H. GRIFFITHS, Vice-lresident EVERIT TERHUNE, Vice-President the Assembly Line WILLIAM A. BARBER, Treasurer JOHN BLAIR MOFFETT, Secretary JOHN H. VAN DEVENTER, JULIAN CHASE, Washington News ielieipa ie 7 THOMAS L. KANE, CHARLES S. BAUR, G. CARROLL BUZBY, FALRENDORE THE NEWS IN BRIEF 69 94 Weekly Ingot Operating Rates BAUR, General Advertising Manager DIX, Manager Reader Service Plant Expansion and Equipment Buying 118 Member, Audit Bureau of Circulations Member, Associated Business Papers Indexed in the Industrial Arts Index. Published every Thursday. Subscrip- } tion Price: United States and Pos- sessions, Mexico, Cuba, $6.00; Can- Single copy, 25 cents. A Num- - ADVERTISING STAFF Just Between Us Two : Robert F. Blair 621 Union Bldg., Cleveland 149 Chilton Bldg., Phila. Products Advertised Hottenstein, 1012 Otis Chicago Leonard, 239 39th St., New York D. | & | ' 1 mm Ryerson Has Thousands Tons Stock for Immediate Shipment Especially now, when steel deliveries are somewhat uncertain, good know that Ryerson has large and diver- sified stocks certified steel hand for quick shipment. Thousands manufacturers every line are daily drawing these stocks meet current requirements. Ryerson imme- diate warehouse shipment forms cheap insurance for the protection your production schedules. Check and play safe your steel requirements. Ten large Ryerson plants, carrying more than 10,000 kinds, shapes, and sizes steel and allied products, stand ready meet both your regular and emergency needs you will get Ryerson certified quality extra cost. you not have the current Ryerson Stock List, shall glad copy. Joseph Ryerson Son, Inc. Chicago, Milwaukee, St. Louis, Cincinnati, Detroit, Cleveland, Buffalo, Boston, Philadelphia, and Jersey City. 32—THE IRON AGE, December 1939 _ ¢ wae 4 3 : 3 q 7 7 I a DECEMBER 1939 ESTABLISHED 1855 Vol. 144, No. asking this question, not suffering from the illusion that The Age has become the Barnyard Journal. The question asked metaphorically, rather than literally. Have You Ever Laid Egg? not need elaborate upon the meaning this expression applied human case this Shakespearian English unintelligible some, will amplify saying that attempting something that fizzles. this connection, permit call your attention what perhaps the largest egg this sort that has yet been laid. refer the settlement the Chrysler strike. This strike, which you know was the largest the history the automobile kept more than 50,000 Chrysler men out work for days. The strike was called the UAW, affiliate, under the direction Richard Frankensteen and others, who Benjamin Stolberg his current expose Communism American labor recently appearing the New York Herald Tribune declares are disciples Stalin. Among other things, the UAW demanded the closed shop, the check-off union dues and the management production After more than sixth year idleness had ensued due these fantastic and im- possible demands, the strike was settled for wage rise three cents hour. Or, you prefer big figures little ones, for millions per year added the Chrysler payroll. Five million dollars year nice boost pay. would like have myself. But when distributed among 50,000 people, shrinks considerably. comes down, figure you will, that little three cents hour. That something for Chrysler labor think about and for every dues-paying member the UAW think about. Three cents hour! What did you get for what you paid? Chrysler employees, get this three cents hour rise, which amounted millions year total, gave $15 millions wages during the days idleness. the end three more years, work steady, the Chrysler boys who goose stepped out the plants obedience Mr. command will back again, financially, where they started from two months ago. For three years the three cent rise will have brought them enough money just what they lost during the strike. This latest victory march the UAW, which consisted three steps backward for each one forward, reminds Napoleon's celebrated march into Russia. was many, many years before the surviving French who participated that march got back what cost them. But then, the French followers Napoleon had the satisfaction, least, knowing that their leader really intended them good. > : | | t ; Thinking the Future, Too! We're heavily booked. making steel fast big, modern, efficient plants can make it. even been obliged turn down orders which were tendered us. Yes, market,” but we’ve been through that before. know that, like the proverbial rainstorm, will end some day always why thinking the future, too. doing our level best meet the urgent delivery demands Inland customers, ever mindful their coopera- tion with through the years. taking every precaution maintain the high stand- ard Inland products. seeking new processes, new methods, new formulae that will cut corners and reduce costs for steel users. Yes, thinking the future, too! SHEETS STRIP TIN PLATE BARS PLATES STRUCTURALS PILING RAILS IRON AGE, December 1939 Y 4 \ | : | Dearborn St., CHICAGO District Offices: MILWAUKEE DETROIT ST. PAUL ST. LOUIS KANSAS CITY CINCINNA ACCESSORIES REINFORCING BARS Tellurium Selenium And ETALLURGISTS years have devoted much time and energy the devis- ing alloys showing improvements their various properties, today each basic metal industry well supplied with variety alloys, each having its own particular the general development alloys, con- sideration has been given goodly proportion the known list ele- ments, and almost endless combina- tions and amounts alloying elements have been investigated. The science metallurgy being comparatively perfection has been reached the field alloying, that the search for new and improved alloys being constant- pursued many laboratories. the copper alloy industry, atten- tion has lately been given the effect copper and copper alloys each element the group tellurium, sele- mum and sulphur, lying the odd division Group the periodic chart the elements. The most pro- nounced result the addition suit- able amounts these elements has ability. Articles Lawson and Metals Division, 1938, Smith, Trans, A.I.M.E., Metals Division, 1938, 128, 325. Metallkunde, Eglesto Trans. Trans. 37, 169. E., 1881, 10, BURGHOFF Research Metallurgist, Chase Brass Copper Co. ° ° ° have reported the results some lab- lines and have pointed out the com- mercial possibilities such alloys. Copper difficult machine, not because high hardness, but rather because its extreme toughness. The addition almost any the common elements, except lead, form the copper alloys commerce, does not improve this condition, but the other hand usually aggravates the con- particular timeliness this article, view the current intense interest the development cer- tain tellurium bearing cop- per alloys. The author here- describes the background and work done tellurium, selenium and sulphur addi- tions copper alloys, and tabulates the physical char- acteristics and uses these alloys. COPPER ALLOYS dition increasing hardness with decrease toughness. chips pro- duced the machining such ma- terials are long and tenuous, tending clog tools. The highly successful and long used free-cutting copper alloys have been made possible the addition small amounts lead, which present the structure such alloys discreet particles globules. These lead particles render chips more brittle and much less con- tinuous that the chips are readily cleared from cutting tools, resulting marked increase ease ma- chining. Experimentation with the elements tellurium, selenium and pears have been held off for many years due the belief that their pres- ence copper and copper-rich alloys was definitely detrimental, with appar- ently redeeming feature. Sulphur, for example, known cause un- soundness tough-pitch copper, and, unless properly controlled, can cause brittleness wrought copper-nickel alloys. The effect sulphur copper the absence oxygen has been studied Siebe and others, the sulphur being found present copper sulphide, consid- ered less harmful than equivalent amount copper oxide. With regard THE IRON AGE, December 1939—35 é | BARS © 7 TABLE Properties Copper Alloys Containing Selenium, Tellurium and Sulphur Composition, Per Cent Ss Ss 0.15 0.23 0.78 0.97 0.11 0.26 Se, Elec- Yield Tensile trical Con- Strength, Strength, Elongation, ductivity, Per Cent per Sq. In. Lb. per Sq. In. Per Cent 50,700 52,100 21.4 99.7 49,600 52,200 14.3 97.8 51,400 52,500 15.0 97.6 52,500 54,300 12.1 95.1 56,500 56,500 7.9 91.6 53,100 56,700 8.6 90.9 51,200 53,200 19.3 98.9 51,600 15.7 98.0 50,900 53,600 15.7 97.4 49,900 53,400 11.4 94.4 52,009 54,200 10.0 92.0 50,700 53,100 15.0 99.5 51,500 53,400 14.3 99.9 50,700 53,100 11.4 98.2 51,200 53,300 10.7 97.1 51,100 54,600 7.1 94.5 cent tellurium fire-refined copper cakes rendered the fine cracks appearing the cakes the first pass through the rolls. When cold, however, this metal was said tough and malleable. The occurrence sulphur quite widespread nature and many metals occur combination with ores. Indeed, the principal copper ores today are sulphide ores. Tellurium and se- lenium are also widely distributed, although not great quantity, and commercial production both from anode slime deposited the electro- lytic refining copper and Selenium exists four modifica- tions: vitreous amorphous form; two unstable crystalline metallic “Modern Uses Non-Fer- rous Metals,” A.I.M.E., 1935. form, gray metallic selenium, which has melting point 217 deg. C., its hoiling point being 690 deg. (423 deg. and 1274 deg. Only this last form interesting Commercial tellurium with melting point 452 deg. and boiling point 1390 deg. (878 deg. and 2534 deg. respectively.) Sul- phur occurs various forms, melting about 115 120 deg. C., and boil- ing 444.6 deg. (239 248 deg. and 832 deg. Solubility the three elements molten copper limited, maximum solubility 1200 deg. (2192 deg. F.) being reported Smith’ 18.15, 4.11, and 1.55 per cent for tel- lurium, selenium, and sulphur respec- TABLE Properties Tellurium-Bearing Copper Alloy Rods, Diameter, Drawn Per Cent Tellurium Tensile Elongation Contraction Relative Izod Content, Strength, Area, Machineability, Impact Per Cent Lb. Per Sq. In. Per Cent Per Cent Per Cent Energy, Ft.-Lb. (90 per per cent zine series) 0.25 54,000 16 54 48 33 (98.5 copper—1.5 per cent tin series) 0.48 56,000 182 (96 copper—3 per cent zinc) 36—THE IRON AGE, December 1939 tively. the solid state these elements are present copper copper tel- sulphide (CueS), are substantially in- soluble and are reported melt 870 deg., 1113 deg., and 1155 deg. respectively. (1598 deg., and 2111 deg. respectively.) The compounds are visible the micro- structure both cast and wrought metal distinct particles, shown Figs. and which show the struc- ture copper-tellurium alloy con- taining about 0.5 per cent little 0.1 per cent tellurium readily distinguished under the micro- scope, occurring particles bluish-gray phase. The melting and casting copper and copper alloys amounts these elements are accom- plished without great difficulty. How- ever, least the case tellurium- bearing alloys, care must taken melting and preparation molds insure production sound Because their low both selenium and sulphur best added the melt the form hard- ener alloys, preferably pounds with copper. trouble experienced volatilization tellu- rium, which has high boiling point, and may conveniently added such hardener alloy. Easily Hot Worked Copper containing tellurium, sele- nium sulphur readily hot worked and may also cold worked exten- sively, although not the same degree pure copper. With regard hot working, copper containing about 0.5 per cent tellurium quite plastic extrusion, even more than pure copper, that more complex shapes and smaller sizes can extruded than with ordinary copper. The surface copper-tellurium material extruded superior, there being present much less the shaggy bark-like surface often encountered extruded cop- per and other high Furthermore, less scaling due heat- ing experienced. The greater high temperature plasticity copper con- taining tellurium probably allied with the plasticity the rium compound the elevated tem- perature, and may associated with the proximity such temperature the melting point, rather tion temperature, which, previously reported 870 deg. mentioned that copper-tellu- rium has been very successfully truded and otherwise hot worked _ _ ‘ ‘ ' ‘ _ 7 ‘above the reported dissociation tem- perature The effect tellurium, selenium and sulphur upon properties copper and copper alloys shown delineation properties such materials containing various amounts the elements question. has reported the effects the three elements copper, while have de- Burghoff and Lawson’ phase, well distributed small par- ticles throughout the metal take advantage its discontinuous and brittle, but not too hard, nature breaking chips machining operations. This situation similar that lead-bearing copper alloys, where the lead present minute particles scattered through the struc- ture the metal and operates im- prove machineability. ductility indicated the values for elongation the tensile test appre- ciable, but none the alloys actually approaches brittle condition. Elec- trical conductivity only slightly di- minished each series, the actual decrease being substantially propor- tional the volume second phase formed each alloy. With regard creases rapidly for additions each ° ° 2—Photomicrograph longitudinal section drawn rod 99.5 per cent copper, 0.5 per cent tellurium alloy. The copper-tellurium com- pound the form dark, elongated particles. diameters. per, 0.5 per cent tellurium alloy, cast, showing diameters. scribed the effect tellurium certain copper alloys. The principal results given these articles will summarized briefly here, and supple- mentary information, hitherto unpub- lished, will included. Useful wrought alloys not con- tain more than about per cent any the three elements, and, when they are present amounts within this limit, tensile strength ness copper and copper-base alloys are substantially unaffected, although there does appear definite re- straining influence upon grain growth annealing. Ductility reduced, although not seriously, the amount these alloying elements increases. expected natural result the Same process that improves machine- ability: the presence Based upon simple laboratory tests alone, sulphur has less beneficial effect upon machineability copper than either tellurium selenium. The lat- ter have much more pronounced effect, and slightly more tellurium than sele- nium required give the same apparent machineability, measured laboratory test. The tensile properties and electrical conductivity values for series alloys con- taining copper, tellurium, selenium and sulphur the form 0.5-in. diameter rods cold drawn per cent are shown Table The negligible differences tensile strength between pure copper and the selenium and tellurium alloys are clearly evident, and noted that the sulphur-containing alloys are only slightly stronger. Decrease the elements 0.25 per cent, effect additional increments being substantial but ever less, with further apparent improvement beyond about per cent. laboratory tests, the time drill found about five times long copper containing about 0.5 per cent tellurium selenium and about times long copper con- taining 0.5 per cent sulphur. Labo- ratory tests have shown that about 0.7 per cent tellurium copper yields alloy equivalent commercial free-cutting brass, com- posed per cent copper, 3.25 per cent lead, 34.75 per cent zinc, for this type cutting operation. Such tests are naturally only indicative qualitative sense, for other factors such permissible cutting speed, sur- THE IRON AGE, December — el- in- eg. nts, int, ele- ked 0.5 stic face high con- llied ellu- with ellu- ex- rked face finish, tool life and chip form enter into the consideration rela- tive machineability materials. Ductility Adversely Affected influence tellurium upon the properties various copper alloys has been the subject considerable study, with results the main those for copper. For example, the hardness and strength 90-10 copper- zinc, 98.5-1.5 copper-tin, and cent silicon bronze are practically in- dependent the amount tellurium present, least within the range per cent tellurium. Ductility, traction area the tensile test and impact value, adversly affected. Results numerous tests three series alloys are given Table II, where alloy composition indicated each case tellurium content. Relative machineability, determined standard 100 per cent for free-cut- ting brass similar dimensions. noted that the machine- ability the tin bronze series much greater degree than the case either the 90-10 copper-zine per cent silicon bronze series. con- nection with this variation effect among different base alloys, in- 38—THE IRON AGE, December 1939 teresting consider the properties tellurium-bearing alloys brasses over the commercial range content, about per cent. has already been shown that the machining qualities for per cent zine (100 per cent copper) and for per cent alloys are greatly im- containing per cent copper and addition 0.2 per cent tellurium. The same was true for 60-40 taining 0.98 and 1.76 per cent tellu- rium, although the tellurium appeared normal alpha and beta crystals. Duc- tility and toughness were reduced other alloys. Table III lists the properties this last series alloys. The reason for the lack improve- ment the high zinc alloys un- known. such alloys the tellurium obviously occurs separate phase other alloys where does im- prove machineability. would appear, therefore, that the nature this extra phase might provide the reason for the effect lack effect upon ma- chineability. Both copper and zinc form compounds with tellurium, and probable that the high copper alloys compound 3—Screw chine products and machined forg- ings made from 99.5 per cent copper, 0.5 per cent tellurium alloy. forms which appears improve ma- chineability. the high alloys possible that zinc major com- ponent the tellurium phase and that the properties this phase are altered character that the phase does not operate break the struc- ture might expected machin- ing operations. Commercial Alloys Much has now been said concerning the merits copper and copper alloys containing tellurium, selenium, sul- phur, and the question naturally arises what alloys, any, this group enjoy commercial The first such alloy made pro- duction basis was per cent silicon bronze, containing 0.25 0.5 per cent tellurium. This alloy high strength characteristics silicon bronzes and the good machineability imparted More recently attention has centered more simple alloy, pure plus 0.5 per cent tellurium, which definitely past the experimental stage and has been steady production for several months. Made both rod and tube form, possesses outstanding combination machineability, forge- ability and electrical and thermal con- ductivity. lends itself well screw machine operations, being definitely f i wt q superior for such use ordinary leaded copper, which contains 1.5 per cent lead, and also free-cutting commercial bronze, composed ap- proximately per cent copper, per cent zinc, and per cent lead. can machined speeds least per cent greater than these alloys, and the same tools, speeds and cutting technique are recommended are used for free-cutting brass. Chips are very fine, and smooth curately finished surfaces are readily The excellent hot working charac- teristics and freedom from fire-crack- ing provide with additional advantages over leaded cop- per and also leaded commercial bronze, which have very limited capacity for hot working and which are very sus- ceptible fire cracking. may extensively cold worked, but less ductile and tough than pure copper. That the alloy making rapid prog- ress industry indicated the variety articles shown Fig. articles consist machined forgings and screw machine products and give some idea uses where ex- tensive machining, forging, high con- ductivity, and copper color are required some Still another alloy which taining 0.5 per cent 1.0 per cent nickel, 0.2 per cent phosphorus, and 98.3 per cent copper. This has the Electric practical and increas- ing application Germany the electric are furnace for making cast iron was described recent issue The following three processes are generally used: (1) Combination blast furnace and electric furnace, the molten iron being transferred directly the electric furnace and there re- (2) Combination cupola and whereby the charge melted the cupola and the molten material treated further the electric furnace this method, commonly known duplexing, the most widely used. (3) charge steel and cast iron scrap melted directly the electric are furnace; this called the thetic” process, and are TABLE Properties Tellurium-Bearing 60-40 Rods, Diameter, Drawn Per Cent Tellurium Tensile Elongation Content, Strength, In., Per Cent Lb. Per Sq. In. Per Cent 84,500 0.98 83,500 14 1.76 82,500 10 Contraction Relative Izod Area, Machineability, Impact Per Cent Per Cent Energy, Ft.-Lb. 54 27 28 31 31 10 23 30 7 tellurium alloy with regard ma- chineability and hot forging and, addition, can hardened and strengthened heat treatment. That is, age hardenable. The nickel and property age hardenability the alloy, and they degree which appreciable but not excessive, that the alloy can readily machined the hardened condition. The effect the tellurium machineability not impaired the additional alloying and treatment. The complete heat treatment the First, solution softening anneal the range 1200 1600 deg. followed rapid and second, hardening treatment which consists reheating about 850 deg. for one two hours. Rockwell hard- ness increased from about the soft condition about age- hardened. Yield strength similarly increased from about 10,000 per sq. in. about 40,000 Ib. per sq. in., and tensile strength from about Ib. Furnace Gray Iron nite The efficiency the electric fur- nace depends largely the quality the electrodes; the graphite electrode preferable the amorphous carbon spite the higher cost the former, according the author; graphite electrodes are always used for furnace units more than tons. also pointed out that desulphur- ization requires strongly basic slag, CaO fluorspar coke powder. The following reactions take place the per sq. in. about 60,000 Ib. per sq. in. Electrical conductivity the hard- ened state about per cent that tively high value when considered with the accompanying high hardness and strength. The development appears im- portant the field forgings which must machined and which are ordi- narily soft condition due the manner their fabrication, hot working operation. After forging, the new alloy can hardened simply the one heat treatment about 850 deg. for period one two hours. Such forgings may ma- chined either before after the hard- ening treatment performed. The alloy may also cold worked before after age hardening that still greater strength Such procedure employed the production rod and tube for screw machine work and values tensile strength high 75,000 per sq. in. are attained, exact values depend- ing upon the finished size the work. Germany CO. CaS insoluble Fe. The average composition good electric High quality cast iron should have low and content, pearlitic struc- ture and fine distribution however, should not lower than 0.3 per cent this content gives opti- mum mechanical properties, according Mr. Sper. The fracture electric cast iron very fine-grained, uniform and dense, even The electric furnace offers refining medium, especially for Ca-Si treatment, which widely used the production iron. THE IRON AGE, December a so se ul- ‘he ‘on ent | the red per age for and ing ge- q | ° GEORGE MOTOK General Metallurgical Research, Republic Steel Corp., Massillon, Ohio ° vacuum extraction process permits the steel maker study oxida- tion products remaining steel well determine the amounts nitro- gen, oxygen, etc. And, these determinations explanation can made variations characteristics steel the same heat from heat-to-heat, such variations not being detectable routine chemical, metallurgical and physical tests. Herein, the author gives case histories showing correlation be- tween gas analyses and variations performance welding steels, spring steels, and stainless steels. Last week, the first section this two-part article, mention was made the effect gases and oxides, and description given the extraction procedure. test was carried out samples steel cut from two plates propeller stock, made from steel (S.A.E. 6130) and both the same composition. These differently when subjected the atomic hydro- gen torch, what called the torch test,” determine weldability. The routine chemical analyses these samples did not reveal definitely the causes for apparent variation weldability the stock. The chemical analysis the sam- ples was follows: Sample No. 0.60 Mn, 0.35 Si, 0.019 0.92 Cr, and 0.22 Va. Sample No. 2—0.29 0.60 Mn, 0.33 Si, 0.016 0.018 1.00 Cr, and 0.22 Va. 40—THE IRON AGE, December 1939 The data Table are the tab- ulated results obtained the two sam- ples the vacuum-fusion process. study the results shows that the best steel has spheroidized structure and lower oxygen, nitrogen and alum- ina, but higher aluminum content. CASE Samples Mn-Si-Mo steel for coal cutter bits were tested determine whether they would brittle when subjected impact testing. The ordinary chemical analyses the two samples showed: Sample No. 0.78 Mn, 0.012 0.016 2.10 Si, and 0.22 Mo. Sample No. 0.78 Mn, 0.012 0.016 1.86 Si, and 0.23 Mo. ° Checked for fractional content gases and oxides, these steels showed the results tabulated Table Ac- the first sample which contained higher content oxygen (as and nitrogen (as silicon nitride) might affected when subjected impact testing. (See Table VI.) And, cor- relate these results with the steel mak- ing practice, necessary take into consideration likewise the time intervals (in advance tapping) which deoxidizers were added. This information given Table VII. The relationship may explained follows: (1) every steel there cer- tain amount oxygen FeO the molten mass before any deoxidation takes place. (2) Adding the steel mass deoxidizes the steel some extent, and most the manganese oxides which are formed will proceed rise the top into the slag. This diffusion from steel slag depends upon the time allowed for the inclusions eliminated. both heats, the fore- going tests, there were added the same amounts manganese, but the time interval, addition tap, less the one heat than the other, and the effect this shorter interval 4 (J I I ( a t ° a a a Cc b 0 - > m ° ° | 7 | time may seen the greater amount manganese oxide which left the steel. (3) The same conditions prevail with deoxidation with silicon. (4) The most convincing indication aluminum addition. same percentage aluminum was add- both heats, but the heat which aluminum was added the tapping time retained more aluminum oxide inclusions than the heat which the aluminum was added min. before the tapping time. There appears appreciable difference the amounts and the dis- tribution the hydrides both steels. However, the case the nitrides was found that one heat contained more total nitrogen than the other. known that ferrosilicon additions the steel mass retain large amounts nitrogen silicon nitride. The silicon nitride dissociated vacuum temperatures the neighborhood 2800 deg. Hence, the case these two steels, the nitrogen appear- ing silicon nitride 2000 deg. The oxides and gases differed amounts, the steel which was claimed brittle containing higher alumi- num oxide inclusions and higher sili- con nitride content than good steel should. The kind deoxidizers, and the time addition before tapping, are hoth important factors making steels the desired quality. The kind and the amount the oxides formed deoxidization, well the elimina- tion these oxides, may read- ily ascertained the vacuum-fusion method extraction. CASE two spring steels similar chem- ical composition, and treated the TABLE Results Vacuum Extraction Gases and Oxides (Total Per Cent) Sample No. Sample No. (Good Weldability) (Poor Weldability) Oxygen 0.0049 0.009 Hydrogen 0.0003 0.0002 Nitrogen 0.005 0.014 0.060 0.035 0.016 0.026 UPLEX iron— manganese- oxide inclusions rimming nital etch, 500 diameters. RON-mangan- clusion silicon- killed steel: as- polished, and 250 diameters. ° ° ° UPLEX iron silicate (dark gray) manganese-sul- phide (light gray globules) high- sulphur silicon- killed steel: as- polished, and 250 diameters. a Leet / > | 7 Nz .C- lat act ik- ne his er- the ass in TABLE Results Vacuum Extraction Gases and Oxides Temperature Probable Per Cent Deg. Reduced Oxygen Hydrogen Nitrogen Sample No. 1900 FeO 0.00081 0.00003 0.0014 2200 MnO 0.00054 0.00010 0.0014 2600 0.00136 0.00007 0.0009 2900 0.00434 0.00010 Total 0.00705 0.00030 0.0094 Sample No. 1900 FeO 0.00122 0.00004 0.0005 2200 MnO 0.00092 0.00004 0.0016 SiO, 0.00092 0.00011 0.0016 2900 0.00275 0.00007 0.0037 Total 0.00026 0.0074 TABLE Distribution Oxygen Content Oxides Per Cent Oxides Oxides Sample No. Sample No. Deg. (Poor) (Good) 1900 FeO 0.00364 0.00548 2200 MnO 0.00239 0.00407 SiO, 0.00254 0.00172 2900 0.00925 0.00585 Total Oxides 0.01782 0.01712 TABLE VII Time Intervals For Adding Deoxidizers Per Cent Added Number Minutes Before Before Tapping Tapping Which Added Sample No. 0.50 2.13 0.034 tap. Sample No. 0.50 1.87 0.035 TABLE VIII Physical and Mechanical Properties vs. Gases and Oxides the Two Samples Per Cent FeO inclusions Per Cent MnO inclusions Per Cent inclusions Per Cent inclusions Izod, Rockwell Sample No. Sample No. (Poor) (Good) 0.0036 0.0055 0.0024 0.0041 0.0025 0.0017 0.0092 0.0058 37.0 67.0 56.5 56.5 42—THE IRON AGE, December 1939 same manner, one far surpassed the other when, radius springs, they were tested destruction 500-ton press. routine inspection tests, both steels had appeared the same performance The springs were made follows: Heated 1650 deg. Air cooled. Reheated 1500 1525 deg. Oil quenched with Houghton No. oil. Drawn 800 deg. The specified analysis and the actual analyses the two samples were Specified analysis; 0.90 1.10 0.30 0.50 Mn, 0.05 0.05 0.20 max. Sample No. 0.90 0.41 Mn, 0.024 0.036 0.08 Si, 0.13 Cr, and nil. Sample No. 0.87 0.40 Mn, 0.024 0.037 0.09 Si, 0.03 Cr, and nil. for fractional content gases and oxides, these steels showed the results tabulated Table Checked And also, from the results shown Table becomes obvious that the considerably greater amount gases and oxides Sample No. over Sample No. accounts for the differ- ence behavior the two steels, al- though the routine chemical ical tests did not disclose any reason for such difference. Considering the individual oxides find that Sample No. contained large amounts MnO, silicates, and indicating that somewhere during the making the heat lot deoxidation products were left the steel. CASE Finally, consider the results tests samples four steels. Three the stainless steels regular mill carbide solution treatment. The fourth sample had been slightly cold rolled but had previously given solution treatment. Routine heat analyses did not indi- cate any significant differences might account for the pitting which was encountered with all four these stainless samples. Because the ratings the steels are little affected surface treatment and because the lack correlation between previous analyses and the ratings, the possibility the influence non-metallics pitting prompted the undertaking the fractional mination. j | ual V ed that fer- ides ined here the tests eels. rhtly been indi- that these tings the bility s on The ordinary chemical analyses the four samples were follows: Sample No. 0.41 Mn, 0.016 0.009 0.41 Si, 10.55 Ni, 18.75 Cr. Sample No. 2—0.065 0.43 Mn, 9.00 Ni, 18.42 Cr. Sample No. 3—0.05C, 0.49 Mn, 0.017 0.36 Si, 9.27 Ni, 0.13 Ti. Sample No. 0.48 Mn, 0.016 Checked for fractional content gases and oxides, these stainless steels showed the results tabulated Table From the vacuum-fusion extraction gases and oxides, may noted that the total oxygen content higher the first two stainless steels tested, steels which offered the greater resis- tance pit corrosion. Considering only the total content oxygen vs. pit susceptibility, however, seems un- likely that comparatively high total oxygen should prevent pit corrosion. more likely interpretation would taking the results obtained for the content oxygen occurring Here, found that the first two steels are higher oxygen than the third and fourth steels. There- fore, pit corrosion resistance might associated with the presence chromium oxides. Chromium nitrides, which are also dissociated the same temperatures with the chromium oxides, are higher the first two steels than the third and fourth. seems equally credible, therefore, that the oxides and nitrides chromium, forming oxide- nitride film the grain surface minimize the susceptibility corro- Conclusion Results such the foregoing ob- tained means the vacuum extrac- tion method throw new light the steel making process. permits the steel maker study the oxidation prod- ucts which remain the steel and check those elements such nitrogen, oxygen, which more and more recognized have important effect the characteristics the fin- ished steel. The problem the steel maker, therefore, (1) determine the un- derlying metallurgical causes for the which are not explained the ordi- nary chemical and physical tests, and (2) apply the knowledge ac- quired systematically possible every detail the steel proc- with the object producing steel that will uniform throughout the heat, well from one heat the next. TABLE Results Vacuum Extraction Gases and Oxides Spring Steel, Sample No. Spring Steel, Sample No. Extraction, Oxides Oxygen Nitrogen Oxygen Nitrogen Deg. Reduced Per Cent Per Cent 1960 Free 0.00908 0.000936 0.00590 0.00259 0.000016 2140 MnO 0.01259 0.000855 0.00169 0.00246 0.00023 2410 SiO, 0.01945 0.000842 0.00212 0.00621 0.000016 2860 Aluminum 0.02404 0.000536 0.00853 0.01200 0.000143 0.00245 silicates 3000 0.03060 0.000324 0.00908 0.01030 0.000115 0.00338 Total 0.09576 0.004293 0.02732 0.03356 0.000290 0.00606 TABLE Results Vacuum Extraction Gases and Oxides SAMPLE Temperature Probable Per Cent Weight Extraction, Oxides Deg. Reduced Oxygen Hydrogen Nitrogen 2400 and SiO, 0.00186 0.00008 0.0039 2600 SiO, 0.00445 0.00013 0.0072 Total 0.01076 0.00022 0.0339 Pit susceptibility characteristics Weight Loss No. In. Mg. Deep Pits 4.8 SAMPLE NO. Temperature Probable Per Cent Weight Deg. Reduced Oxygen Hydrogen Nitrogen 2100 0.00005 0.0064 2400 and SiO, 0.01840 0.00010 0.0150 2600 SiO, 0.00490 0.00031 0.0172 Total 0.02942 0.00046 0.0736 Pit susceptibility characteristics Weight Loss No. In. Mg. Deep Pits 6.9 SAMPLE Temperature Probable Per Cent Weight Extraction, Oxides Deg. Reduced Oxygen Hydrogen Nitrogen 2100 0.00010 0.0090 2400 and SiO, 0.0008 2600 SiO, 0.00258 0.0068 2900 0.00258 0.00021 0.0082 Total 0.00645 0.00036 0.0248 Pit susceptibility characteristics Weight Loss No. Mg. Deep Pits 99.6 SAMPLE Temperature Probable Per Cent Weight Deg. Reduced Oxygen Hydrogen Nitrogen 2100 0.00005 0.0044 2400 MnO and SiO, 0.0007 2900 0.00170 0.00021 0.0052 Total 0.00552 0.0125 Pit susceptibility characteristics Weight Loss No. In. Mg. Deep Pits 140.7 110 THE IRON AGE, December 1939—43 1 rs F es. as 0.30 Si, 7 ‘ | q | | | | PORCELAIN ENAMELED FACTORY BUILDING demonstration the versa- tility its own product, the Ferro Enamel Corp., Cleveland, recently completed new building, unique that porcelain en- interior finish. The roof, stack, gables, trim, gut- ters, window-sash and door are fin- ished porcelain enamel, and inside partitions separating the offices, labo- ratory and plant are also porcelain enamel. The objectives construct- ing the building this material were first, demonstrate the possibilities for porcelain enamel the factory- building field and, secondly, take ad- vantage savings made through = the use the company’s own product. The roof believed the first self-supporting porcelain enameled steel roof ever erected, and for that reason has attracted considerable in- terest and favorable opinion from builders. was found that the Kor- Lok system, developed the Kor- Lok Co., Cleveland, offered ideal means handling enameled roofing. This system makes use patented interlocking formation nates all exposed bolt holes for fasten- ing the sheet the roof deck. All bolt heads are concealed and protected the overlapping sheet. This type sheet permits the erec- tion the main portion roof, new Ferro Enamel Corp. building has porcelain en- ameled roof, sash, gables, trim, gutters, window sash and door. The interior partitions also are porcelain enameled. 44—THE IRON AGE, December 1939 siding area, with standard-size punching holes required. For the balance roof siding area, the sheets can cut size prior porcelain enameling. also prac- tical ship standard sized sheets job and then any necessary cut- ting size with small power saw. Since only thin coating porcelain enamel used, serious chipping the enamel along such cut edges re- sults. For the building shown the ac- companying photo the sheets that were not standard size were cut size before porcelain enameling. be- lieved that for the average industrial roofing job, this practice feasible and desirable, although not essential. Where the underside the roof not covered secondary facing material, such celotex board similar material, possible and quite desirable coat the under- side the sheets with white porcelain enamel. This increases the cost slightly, since two firing operations are then required, but the advantages gained more than compensate for the differ- ence, White light reflectance values this way. clean such roof, only necessary wash down with water and perhaps little soap. increasing field anticipated the company for porcelain enameled roofing, now that the first practical industrial installation 7000 sq. ft. has been made. This type roofing should particular interest those industries where process-fume conditions are severe the more common types roofing. The steel partitions the shown herein, were finished rich shade brown porcelain enamel and were made the Hauserman Co., Cleveland. This installation considered demonstration the feasibility porcelain enamel- ing standard metal partition units for offices, stores and laboratories. Easily cleaned, requiring periodic refinish- ing, these partitions are expected retain their quality in- definitely. All the industrial window-sash for the building were porcelain en- ameled, using ground coat with black overspray, produce fine textured, tight enamel finish, re- sistant action the most severe weather. The flanges buried the wall also have this permanent protec- tion against corrosion from the damp- ness that often collects there. for good electroplate clean sur- face. Surfaces which appear clean the naked eye may not clean all, but may covered with very thin films oil, grease, fat, oxide, etc. This contamination readily defeats the operation plating. other words, the surface plated must chemically clean. obtain clean surface several operations are necessary. First the surface oils, greases and fats, well the dirt accumulations due han- dling, must removed. Second, the oxide film, from whatever cause, such rolling mill scale, fire scale, rust, tarnish, must removed. Cleans- ing materials which readily remove the first group are not adaptable the removal the second and the acids ordinarily used remove the second group are not efficient the first group. The process, therefore, involves two distinct cleaning opera- The first operation cleaning essentially degreasing operation. degreaser for use the first group materials. Its use distributed over the following cleaning jobs: (1) Removal rolling and rust- proofing oils before plating from sheet stock, rolled forms, shapes, drawn tubes and other mill products which are oil protected against rust and tar- nish during shipping. (2) Removing stamping director Magnus Chem- ical Co. The why and how chemically cleaning different types metals and alloys prior electroplating application other high grade finishes. The equip- ment used and the characteristics the various techniques. ° ° MITCHELL* ° ting oils prior bright dip and prior polishing and buffing. these are not removed, bright dipped parts will non-uniform color. Polishing and wheels become loaded with the oils and cause smudging the work, reduce the cutting rate, are more difficult wipe, and shorten wheel life. (3) Removing stamping, cutting and drawing oils prior plating order keep subsequent solutions such alkali cleaners, acid pickles, cyanide dips and plating solutions free the oil contamination. (4) Removing stamping oils from pre-plated stock after stamping and forming. Many articles, such nickel used for vanity are stamped and formed after plating and the use oil the dies avoids streaks. (5) Removing oils woven wire cables prior ° such the cable used for the eye glass temple frame. (6) Removing stamping, drawing and cutting compounds from alumi- num prior coloring anodizing. (7) Removing quenching oils, and lapping and buffing compounds from work prior plating. Although just portion the appli- cations cleaning are mentioned the reader is, doubt, quite able think many others. The degreaser shown Fig. equipped with two- strand, cross rod conveyor with vari- able speed drive. Heat supplied steam coils maintain the vapor temperature 188 deg. The work being conveyed through the ma- chine vapor cleaned while passing over the dirty boiling liquid. The work then passes sprays clean solvent which slightly cooler than the vapor. The THE IRON AGE, December ial ly, led cal ft. ing ime and nan nel- for ish- ash en- the athens ABOVE FIG. equipment the vapor type. Courtesy Detroit Rex Products Co. vapors are condensed the work, due the difference temperature the work and the vapor, give final cleaning. The overall dimensions the equip- ment are ft. in. long ft. in. wide and ft. in. high. The sol- vent capacity gal. The rate production from tons miscellaneous metal parts per hour conveyor speed ft. per min. Parts are loaded and un- loaded from the degreaser the end the machine. However, the con- veyor may made part gen- eral system covering the entire series operations the plating cycle well extend back preceding oper- ations. Under average conditions the degreaser uses gal. liquid per 8-hr. day. The second operation cleaning essentially descaling operation. The scale may rolling mill scale, fire scale, heat treating scale, sand scale, rust oxides from whatever source. 46—THE IRON AGE, December 1939 There are numerous ways remov- ing this deposit, the selection which depends upon the type work, its composition contour. Some the more common ways em- ployed are grinding, honing, rubbing, polishing, roughing, dry buffing, sand-blasting, tumbling, sand- ing and pickling. the present work, consideration will confined clean- ing the electric When descaling with hydrochloric acid, concentration about per cent will act quicker where rust The bath should heated between and 150 deg. F., the high temperature being preferred. case sulphuric acid, which con- siderably cheaper, the concentration should between and per cent, and the temperature the bath be- tween 120 and 200 deg. The Hanson-Van Winkle-Munning Co. electrolytic bright cent sulphuric acid current den- sity from 150 amp. per the work being made the cathode. The scale effectively removed from min., but the work will remove this smut the work re- moved, rinsed cold water and placed work made the anode for period BELOW FIG. Cleaning aluminum parts Hall Aluminum Air Craft Co. i this bath the acid made from per cent and the current density from 100 150 amp. per sq. ft. this system high current densities coupled with low temperatures—up deg. F.—produce good bright sur- faces. With too low current density too high temperature the surface will clean but not bright. The nor- mal results from the process are silvery surface free from smut and with slight degree etching. The high current values require good elec- trical contacts and many instances : — J | | 3 cooling the anodic bath needed insure bright surface. the complete automatic plating system alkaline cleaner usually inserted preceding the cyanide bath remove the cutting oil, greases and dirt from the surface. cleaner with per cent caustic soda, the balance being silicate and phosphate, may used. soap should pres- ent this interferes with the conduc- tivity the solution, and, further- more, soap will cause dragged over into the plating cycle. For die cast work, where slightly etched surface desired for adher- ence the plate, about per cent free caustic soda should added the mixture silicate and phosphate. The silicate this case acts buffer agent. the etched surface not desired, the caustic soda omitted. Unless the work adequately buffed with sodium silicate, excessive tarnish- ing and etching the work will re- sult. German silver, antimonial lead, white metal, Brittania metal, terne plate, and zine such used the manufacture novelty jewelry and similar work are handled the same manner above. For silver and brass, the procedure the same for copper articles except that the al- kaline mixture should run between and per cent caustic soda. should buffed with some silicate and should made free-rinsing the addition phosphate. The cleaning and stripping alu- minum particular interest the aircraft industry, and fact this in- dustry has gone enormous expense materials, methods and equipment improve this phase their opera- tions. has long been known that ENTH Series Articles the Technical and Economic Aspects Metal Cleaning and Finishing weather aged aluminum takes paint well, that is, the bond between the paint and the aluminum sheet was quite firm. Since paint would not bond the dead smooth surface the new aluminum, some method was sought which would give teeth the alu- minum. Aluminum workers turned the industry and the experience available with iron oxide. The iron oxide was applied the aluminum sheet and baked, then removed var- nish remover and the surface found bond between the paint and the sur- face. Another primer, zinc chromate, was used and was found have greater protective value than the iron oxide and possessed the added feature not having any reaction with the aluminum surface does iron oxide. Another problem presented the aluminum users was that removing the paint. the aircraft industry the complete removal the paint was matter great importance. new plane design must painted, and after its trial runs all the paint must removed right down the metal and new coat applied. Here was cleaning job small pro- portions. was found that soap addition per cent for cleaning aluminum hot bath (200 deg. F.) resulted the formation insoluble soap, FIG. 3—An installation for solvent emulsion cleaning metals. ordinary fatty acid soap was used. Since most water contains soluble cal- cium and magnesium salts, which immediately react with the ordinary soap give insoluble calcium and magnesium soap, synthetic soap was evolved. combining this synthetic soap with the compounds formerly used, and based tri-sodium- phosphate and soda ash, the phosphate being buffed with silicate prevent excessive etching the aluminum surface, all the troubles previously ex- perienced were and the alu- minum surface was properly prepared for the paint coat. Fig. shows the bath used the plant Hall Aluminum Air Craft Co., Bristol, Pa. The tank ft. and contains approximately 3500 gal. solution. The average con- sumption cleaner for this operation lb. per month. The bath kept temperature from 140 150 deg. F., and aluminum cleaned min. Paint removed from min. Original concentration oz. per gal. water. Before leaving the general subject cleaning the use solutions other than alkaline, some mention should made some the solvent emulsion cleaning processés. These are used remove the bulk the oil, grease and other foreign matter prior immersion electric cleaning bath and soften and remove oils unattacked alkaline solutions, for instance sulphurized oils, pigmented drawing compounds, metallic soaps, The work im- mersed liquid solvent emulsion, usually room temperature, which penetrates the oil film and, after drain- ing, rinsed which turn causes spontaneous emulsification place. The oil, dirt and smut then readily removed subsequent clean- ing operations, and for that matter often largely carried away the rinse water. The use this method illustrated Fig. which the third tank back the electric cleaning tank, the tank adjacent the spray