The Iron Age 1934-07-26: Vol 134 Iss 4

THE IRON Managing Editor Editor News Editor Machinery Pittsburgh Detroit Boston Cleveland Chicago Editor Emeritus Washington Cincinnati of — = = — — — — — = — ontents CODE 1934 Uncle Sam Goes 0. . . . . . in- Determination Nitrogen Heat-Resisting Steels Interpreting Creep Tests High Temperatures Industrial Highlights Pictorially Displayed Running Iron Blast Furnace for Ammonia Manufacture New Things Materials and Processes Attractive Finish Helps Metal Products Sales Welding Rod Coatings ers New Equipment News Personals and Obituaries ron Washington News Automotive Industry Construction and Equipment Buying Products Advertised Index Advertisers ter ree ing 5 THE IRON AGE PUBLISHING COMPANY FRANK, President GRIFFITHS, Secretary BAUR, General Advertising Manager de- PUBLICATION OFFICE: Corner Chestnut and 56th Sts., Philadelphia, Pa. EXECUTIVE OFFICES: 239 West 39th St., New York, Y., ted ADVERTISING STAFF Member, Audit Bureau Circulations Emerson Findley, 311 Union Cleveland = Member, Associated Business Papers B. L. Herman, 675 Delaware Ave., Buffalo, N. Y. ' its | H. K. Hottenstein, 802 Otis Bldg., Chicago 7 Published every Thursday. Subscription Price: Peirce Lewis, Woodward Ave., Detroit United States and Possessions, Mexico, Cuba, Charles Lundberg, Chilton Chestnut $6.00; Canada, $8.50, including duty; Foreign 56th Sts., Pa. her $12.00 year. Single Copy Cents Ober, 239 39th St., New York ves W. B. Robinson, 428 Park Bidg., Pittsburgh Cable Address, ‘‘Ironage, Sweetser, 239 West 39th St., New York Warren, Box 81, Hartford, Conn. the 7 EIGHTIETH YEAR SERVICE THE METAL WORKING INDUSTRY THE IRON ACE......... JULY 26, 1934 Steels for Every Purpose —All the newer steels, special alloys, copper, brass and allied metals, with immediate shipment assured New products—improved products, require special steels developed particularly for specific requirements. These steels are stock ready ship. Ryerson equipment Ryerson ex- perience—and Ryerson or- ganization assure their im- mediate dispatch, accurate your specification and cut your requirements. Ryerson engineers, thor- oughly experienced steel ALLEGHENY METAL (Stainless 18-8) This well-known leader among the stainless steel 18-8 group affecting economies and increas- ing saleability nearly all lines industry. Available sheets, plates and bars. Also castings for ornamental purposes. Write for Allegheny Metal booklet. men, familiar with all the newer steels, offer you their help solving any special problems. Call without obligation. The Ryerson Stock List your guide more than 10,000 sizes and kinds steel products carried TOOL STEEL Ryerson has shown some remarkable results. new revolutionary process produces dense, fine grain structure. develops keen, durable cutting edge with minimum distortion for water hardening Users report real operating economies. Write for sample test. stock for immediate ship- ment, Ten plants give na- tional service. There plant near you. Let send the latest Stock List. JOSEPH RYERSON SON, INC.; Chicago, Milwaukee, St. Louis, Cincinnati. Detroit, Cleveland, Boston, Phila- delphia, Jersey City. YOUR MOST COMPLETE STEEL GUIDE— More than 200 pages infor- mation steel that ready ship. you haven’t copy, the nearest Ryerson will bring return mail. 1m . = spe ive “1934 » tro m ° n 1C orc THE IRON AGE ... JULY 26, 1934 ESTABLISHED 1855 Vol. 134, No. Uncle Sam Goes Shopping the last year Uncle Sam has been spending nearly $400,000,000 month. has been the best customer many important industries. Through all, has been very anxious protect the small buyer against the large. has insisted that the same prices quoted every- one. this policy discarded? Uncle Sam finally decided that his large purchases entitle him special treatment the expense the smaller consumer? Compared Uncle Sam, all buyers are small, and they would like know. would those who sell Uncle Sam and who operate under codes fair competition which heart- ily approved. EARLY month has passed since the President issued the highly con- troversial executive order permitting reductions from code prices mitting bids Federal, State and mu- nicipal contracts. The full import the order not yet understood. Interpreta- tions and explanations have been offered, but they have been inconclusive. Indus- try has right know more. not interested much the exact legal meaning the order the intent. What prompted this rather obvious at- tempt nullify the price stabilization which has been accomplished under the NRA codes? the Government’s far-flung activity. many public works projects labor the overwhelming cost item. Does Uncle Sam intend extend his shopping activ- ities the realm wages? This would seem consistent. The labor cost ton steel going into post office into factory addition automobile. are the other costs. But the private buyer now expected pay more. The private seller also expected accept less for his product. Whether not agrees not the question. Uncle Sam has stated his position. NDUSTRY has the right know what behind Uncle Sam’s sudden decision shopping. GERKEN, News Editor, THE IRON AGE ati. ila- 7 n Determination Soluble and Insol amount nitrogen steel, and its probable effect the prop- erties iron, was much debated question far back that time Allen’s method was the best applied plain steels. This was par- ticularly regards his distilla- tion idea, which, suitably modified, currently important when nitrogen fixing elements are present, such titanium and vanadium. The latter element will cause large portion the nitrides the steel exist form undecomposable scheme even though much greater strength hydrochloric acid used than prescribed. Some chemists recommend the whereby the insoluble nitrides are fil- 1A. Allen, Journal Iron Steel In- stitute, Corrosion and Heat- MORRIS JOHNSON Chief Chemist, Crucible Steel Company America tered out and the nitrogen contained therein determined Dumas’ com- bustion process for nitrogen. The writer finds very convenient and rapid decompose the insoluble dissolving such nitrides C.P. perchloric acid, together with some concentrated H,SO,. bit ironical that the much- feared nitrogen now being recom- mended and broadcast advertise- ments addition high-chro- mium irons produce small grain size castings and improve machine- ability. However, increase the nitrogen content corrosion-resist- ing steels may have some undesirable influence the cold forming prop- erties the highly alloyed corrosion- resisting steels, nitrogen does in- crease their hardness and, the same tility. Thus far there evidence loss nitrogen the remelting scrap and this may, remelting goes on, result nitrogen content that will objectionable where maxi- mum ductility required. The writer has tried distinguish between the insoluble nitrogen and the nitrogen that soluble the dilute acid. ,It believed that this differ- ence may some measure the al- loying element’s effective value 10—The Iron Age, July 26, 1934 Windshield for preventing back suction and for protecting the flames under the flasks dis- tilling apparatus the left. This shield made from rolled stain- less steel, and hooked the front framework the stand Fig. paratus for the determi- nation soluble nitro- gen stainless heat- resisting steels. inhil corr the effici denu cent, and consi resul chror comb the per must perm tant ter sp. tables apply and acids matio impor titani when the also res ide ceptio ways The dizing > igs 4 ete | A +? . 2) uble Nitrogen Ferrochromium, Resisting Steels corrosive agents. this yardstick, the element titanium should more efficient inhibitor this type cor- rosive attack than vanadium. Molyb- denum “18-8,” even 2.50 per cent, not effective this respect. See Tables III (Ti), (V), (Mo) and (Ti). “18-8” steel with considerable percentage (1.23) was tested also and the results are shown Table VI. Table III shows that when titanium chromium steel, the nitrogen forms different compound with the Ti. The combination becomes more and more the content increases about 0.40 per cent and higher. course, there must enough nitrogen present permit the reaction. That the compound highly resis- tant non-oxidizing acids, such acid, even when the lat- ter acid concentrated form (1.20 sp. gravity), evident from the tables. Therefore necessary apply drastic treatment with boiling and fuming perchloric-and sulphuric acids dissolve the compound reasonable length time. The for- mation this acid and alkali-resist- ing compound is, all probability, important not essential reason why titanium acts powerful inhibitor intergranular corrosion. stated the literature that when titanium alloyed with steel the presence sufficient nitrogen and carbon, the result production The tables given herein also show that this substance high- resistant boiling sodium hydrox- ide the dilution used for dis- tillation “soluble” nitrogen. course, air present, with the ex- ception the initial air that al- the distillation flask. nitride readily soluble oxi- dizing mixtures, such dilute sul- analytical method for in- vestigating the nitrogen content corrosion resisting steels differ- entiates between “soluble” and “insoluble” nitrogen. Such pro- cedure has important signifi- cance, relation intergranular penetration corrosion-resisting the effectiveness one nitrogen fixing element compared an- other, and, therefore, its value pointed out that the increasing nitrogen content high-chro- mium steels may disadvantage the nitrogen increases scrap remelted from such steels. The propaganda the effect that ni- trogen produces smaller grain size such steels (which does) will tend the production higher nitrogen scrap. This objec- tion carried too far increased hardness often results less duc- tility sheets. Therefore the de- termination nitrogen such steels considerable impor- tance steel makers, and the method described herein phuric acid (1:3) containing concen- trated nitric acid, i.e., 1:3 plus ml. concentrated nitric acid. See “Determination Titani- Color Corrosion Resisting Steels,” THE IRON Aug. 24, 1933. evident from the tables therein that vanadium and columbium form similar more less acid-resistant compounds containing nitrogen. analogy and appearance these are car- bon compounds also. That other ele- ments, such zirconium, perform like manner expected. Fur- thermore, the tables show that when these insoluble nitrogen compounds are exposed air, over longer periods, that some decomposition occurs solutions the steel also. Determination Procedure The most rapid and accurate meth- ods for the quantitative analysis nitrogen steel are based Allen’s method for soluble nitrogen, i.e., sol- uble dilute sul- acids water bath tempera- ture. steels which contain certain non- ferrous elements, such titanium and vanadium, considerable portion the nitrogen will found the in- soluble residue associated with the black residue. This will also still re- tain part the nitrogen even after subsequent distillation with sodium hydroxide boiling temperature, indicated the tables. This nitrogen containing substance best filtered, before the distillation, pad washed asbestos with slight suction and washed with dis- tilled water few times. lain Gooch crucible well adapted this work. These washed insol- ubles are gotten into solution heat- ing boiling temperature with C.P. per cent perchloric acid together with some. concentrated sulphuric acid. This solution then distilled separately. The procedures will described detail the following paragraphs. make 0.01 normal sodium hydroxide standard, weigh 0.85 gm. stick sodium hydrox- ide glass pan, dissolve the NaOH and dilute 2000 ml. with distilled water, and then mix well. Determine the relation between this NaOH and the 0.01 normal sul- acid. Theoretically, 0.80 gm. The Iron Age, July 26, ne- st- ble in- ing xi- ish ute er- al- back the dis- This tain- the NaOH dissolved and diluted 2000 ml. 0.01 normality. make 0.01 normal sulphuric acid solution, stock mixture made diluting 8.6 ml. concentrated (1.84 sp.g.) 3000 ml. Mix well and allow cool room tem- perature. Then dilute 800 ml. the stock 8000 ml. with distilled water. Consequently ml. 0.01 solution C.P. sodium carbonate. This sul- phuric dilution should checked against C.P. sodium carbonate ob- tained igniting 100 mgm. and mgm. C.P. sodium oxalate plati- num crucibles low red heat until the black char has disappeared. The 100 mgm. and the 0.050 mgm. the oxalate should yield 79.1 and 39.5 mgm. respectively C.P. sodium car- bonate. actual case, 39.8 and 39.6 mgm. were obtained from the the oxalate and 79.0 and 79.2 mgm. from the 100 mgm. portions the C.P. Na,C,0,. The oxalate must converted carbonate the lowest red which the black char can removed. the oxalate overheated some will changed NaOH, thereby in- troducing error. The white ash then rinsed into 500 cone flask. Dilute 250 ml. with add two drops in- dicator, and then titrate until the pink shade changes the first brown shade. Dilute the remainder the approximate 0.01/N/H,SO, with H,O, calculated amount proportion the acid’s excess over ml. 0.00053 gm. sodium carbonate. Theoretical- ly, ml. 0.01/N/H,SO, 0.00014 gm. nitrogen. The indicator solution made dissolving 0.25 gm. sodium alizarine per cent sodium hydroxide so- lution made dissolving 300 gm. C.P. nitrogen-free flakes H,O and diluting 500 ml. with H,O. This must well mixed. The following the general method checking standard solutions and performing standardization calcula- tions. the ignition mgm. sodium oxalate, 0.0394 gm. Na,CO, was obtained. This was then titrated with the approximate 0.01/N/H,SO,, and required 72.3 ml. the latter neutralize the carbonate the in- dicator; mathematically, 0.0394 72.3 check run with the carbonate obtained from 0.100 gm. oxalate gave ml. 0.01 equals This average value ml. 0.0005466 gm. and this calls for dilution the 7600 ml. left from the 8000 ml. (400 ml. 12—The Iron Age, July 26, 1934 Table Per Cent Year Nitrogen Determined Bessemer ... 0.010 0.013 1919, 1927 No. 0.010 6.012 1928, 1932 No. Ingot Iron 0.004 0.005 1923, 1925, 1931, 1932 106. Nitrallo, 0.007 0.011 Stock Table 2—U. Bureau Standards’ Steels Official Per Cent Nitrogen Procedure eee ee 0.004 0.005 0.006 0.004 0.005 No. 106 (Nitralloy) . 0.007 0.011 0.008 0.009 0.011 No. 101 (18-8 0.026 0.028 0.026 0.026 having been measured out for the testing). Therefore, 7856 Therefore, the remaining 7600 ml. the sulphuric solution must diluted 7856 ml. with H,O have the value 0.01 checking the NaOH solution with the 0.01/N/H,SO,, prepared just described, 38.1 ml. the NaOH Acid Alkali 40.3 38.1 (300 ml. the 1798 2000 ml. alkali having been re- moved for test- ing) Therefore, the 1700 ml. alkali must diluted 1798 ml. equivalent the 0.01 sulphuric acid standard. Distilling Apparatus Described The distilling apparatus shown Fig. consists six-burner stand and metal condenser tank. The stand will accommodate six round bottom, 800 ml. pyrex glass boiling flasks with No. stoppers. These flasks are about 14% in. tall with in. O.D., and the necks are in. long. The standard size bulb oval and in. long in. diameter. The tin condenser pipes, which are connected with the distillation flasks rubber tubing (5) Fig. are water cooled (4). The writer cushions the flasks (1) plac- ing under each them six thin rings asbestos paper. The 500 ml. re- ceiving flasks, (2), have glass tube connecting, means short piece rubber tubing, with the out- let end the tin condenser tube and reaching the bottom the receiv- ing flask. This glass tube carries the ammonia water distillate into the measured portion the 0.01/N/- This very satisfactory, com- pact and attractive looking outfit can purchased shown Fig. from scientific laboratory supply houses. The writer also adds trough thin (about mm. wall) sheet lead (not shown Fig. carry off the considerable water that forms along the front face and drips off the bottom edge the cooling tank. The trough not essential, but easily formed hand and eliminates the nuisance dripping water. The method determining soluble nitrogen follows: the chro- mium content medium, dissolve 5.0 gm. drillings 500 ml. cone flask with 1:1 HCl. Use 100 ml. the acid the sample the stainless heat-resisting type, and gm. the nitrogen much excess 0.030 per cent. Place the flask, which the same kind used (2) 150 ml. beaker inverted over the mouth the flask prevent any laboratory fumes from entering during the dissolving period, and possible all dissolving, distilling and titrating are better accomplished room free ammonia and acid dissolve the drillings, although the time depends the kind and amount alloys present. there black residue in- soluble materials, should filtered out asbestos pad, preferably porcelain Gooch crucible. best use washed asbestos and wash few times with distilled water during filtration. Transfer the filtrate and washings the distilling flask (1) Fig. and hold the washed residuals for digestion fuming perchloric acid. This latter procedure will described later. During distillation first make sure that the water flowing freely through (4) Fig. However, the apparatus should flushed before distilling the ammonia from the fil- trate and washings from the insoluble materials, etc. this, charge each flask with 350 ml. H,O, two three pieces mossy C.P. and ml. the per cent NaOH, the case plain steel. stainless grades are being analyzed add ml. the NaOH instead ml. Connect all flasks shown Fig. and raise the heat gradually until all solutions are boiling. Distill over into the empty receiving flasks 250 ml. dis- tillate. This then rejected order cleanse the apparatus any am- monium fumes acid. Ban. ee ; cal Bri cel P bur 7 wit the are are due U nl tal Star cont Z1v e q stan meas mear This the ing with color this the ; still 10.3 chem The remaining liquid the distill- ing flasks can then used for the first runs the actual tests. That is, the before-mentioned filtrates and washings from the insoluble nitrogen can now added the alkaline liquid the distilling flasks after cooled about deg. The volume then again brought 350 ml. with and the stopper inserted quickly. Bring this liquid slowly boil and again distil over, 250 ml. into the re- ceiving flasks, which have been previously placed ml. the 0.01/- carefully measured from burette. the nitrogen exceeds 0.050 per cent and 0.100 per cent, use ml. the 0.01 acid the re- ceiving flask. Titrate this distillate with the equivalent 0.01/N/NaOH until two drops change the color the distillate from lemon yellow brown. Two drops the indicator are added before titrating. Blanks are run all operations and de- ducted. The 0.01/N/H,SO, should checked for its nitrogen value against United States Bureau Steel Standards which there are several. For ex- ample, the Bureau determined the to- tal nitrogen their No. 101, 18-8 standard, both the vacuum fusion method and Allen’s method, and found 0.028 per cent. The nitrogen contents other standard steels given Bureau publications are shown Table The 18-8 standard has only 0.06 per cent carbon, and the total nitrogen revealed the soluble nitrogen determination true all the standard steels Table One may find low 0.000115 gm. for empirical factor. Calculation Percentage The ml. the 0.01/N/H,SO, are measured into the receiving flask from burette. The latter should rinsed least three times with ml. the standard acid beforehand. About 250 ml. the solution stainless grade were passed down through the tin condenser pipe means the glass tube which dips the bottom the receiving flask. This distillate mixed together with the ml. standard acid swirl- ing the flask and then titrated with the 0.01/N/NaOH brown color. certain stainless grade this operation required 10.3 ml. the NaOH. other words, 10.3 ml. the ml. the 0.01/N/H,SO, were 10.3 14.7 ml. the which were consumed the ammonia coming from the stainless grade sam- ple and from that contained the chemicals the blank. previous Fig. 2—The apparatus employed for insoluble nitrogen digestion. determination this blank was found 1.7 ml. 0.01/H,SO, used. Therefore, 14.7 1.7 standard acid used the the steel. Then per cent check run using gm. steel gave 0.0381 per cent there- fore, will seen that the method checks well. the distillate turns brown pink immediately adding the two drops indicator, shows, course, that the nitrogen high. such event, add ml. more the standard acid from burette add enough dis- charge the brown color. Then pro- ceed titrate brown with the 0.01/N/NaOH. One should also re- peat the analysis placing ml. the 0.01 acid the receiving flask place enough give fair excess the This will indicated the amount 0.01/N/- required discharge the brown color produced the indicator added before the titration. The distillation for cleansing the apparatus can run the start the work period and the usual blank gotten titrating this distillate, all the day’s analyses may then made without further flushings. The apparatus for insoluble nitro- gen digestion shown Fig. consists six 800 ml. flasks the same and kind are shown (1) Fig. for distillation. This illustration happens show two Strauss testing flasks the stand the time. passing might well note that the Strauss testing flasks take No. stoppers, are in. high, hold 500 and have 25/32-in. neck. All flasks rest copper Table 3—18-8 Steels With Titanium Cent Per Cent Direct PerCentC Determination Soluble Insoluble Total 0.06 0.138 0.054 0.007 0.961 0.052 0.011 0.063 0.06 0.20 0.005 0.010 0.006 0.016 0.009 0.006 0.016 0.06 0.32 0.004 0.012 0.016 0.006 0.012 0.018 0.11 0.45 0.002 0.005 0.010 0.015 (0.004) 0.005 0.012 0.017 0.05 0.60 0.005 0.011 0.016 0.005 0.012 0.017 0.09 1.13 0.005 0.042 0.047 0.007 0.039 0.046 0.11 1.28 0.003 0.045 0.048 0.003 0.045 0.048 0.97 1.12 0.004 0.059 0.087 (0.010) 0.019 0.069 0.086 The Iron Age, July 26, 1934—13 the any and the ered yin best and ming sure reely the efore each and the the ect all raise the dis- order am- _ | Table 4—Stainless Per Cent Chromium Steels With and Without Vanadium Carbons all Below 0.08 Determination 0.040 Per Cent none 0.040 0.045 0.016 0.016 0.016 Per Cent Soluble Insoluble Total Nitrogen Nitrogen Nitrogen 0.043 0.043 0.040 0.040 0.042 0.051 0.041 0.049 0.045 0.046 0.048 0.037 0.044 0.038 0.044 0.033 0.036 0.032 0.035 0.022 0.029 0.022 0.033 0.015 0.034 0.015 0.033 0.014 0.036 0.012 0.039 0.016 0.040 0.017 0.038 none none 0.009 0.008 0.004 0.002 0.007 0.006 0.003 0.003 0.007 0.011 0.018 0.023 0.027 0.024 0.021 *The figures given this column are obtained ignoring the insoluble residues. wire gauze fastened the top the heating stand which in. long, in. wide, and in. high. The con- densers, (2) Fig. are 12% in. high with in. 10-in. O.D. bar- rel containing five inner bulbs. The flasks are firmly held clamps that are fastened %-in. diameter steel rods in. high. These rods are threaded and screwed into the back the stand and both condensers and flasks are clamped them. The flasks are heated ordinary Bunsen burners which are not at- tached the stand. this method one able secure greater flexibility and regulation the amount heat applied each flask. Following the method used for solution the nitrogen the insol- uble residues. The asbestos pad with the black layer dropped into the distilling flask carefully avoid any the asbestos, etc., lodging the neck the flask. This black in- soluble should the bottom the digester. Add ml. per cent C.P. perchloric acid and ml. concentrated H,SO, water started through the series condensers which are connected tandem. Heat from the Bunsen burn- ers applied until the acid mixture fumes. necessary this mixture may boil until all the black color disap- pears and there remains only the white asbestos and the solution all the nitrides. This operation takes about min. not permit the fumes rise higher than the sec- ond bulb the condensers tem- porarily removing the burner nec- essary. Fig. shows four flasks action once (and two Strauss tests). The fumes are plainly visible (1) Fig. When the insol- ubles are thus dissolved, remove the heat and let the flask cool with the condensing water still flowing. Then rinse down the inner tubes the condensers. When cold, disconnect the flasks. Rinse down the neck and sides the flask using about 100 ml. Then add the cold solution ml. the per cent NaOH solu- Table 5—Non-Austenitic Stainless Chromium Steels With and Without Titanium All Carbon Percentages Below 0.08 Direct Determination 0.025 0.0090* 0.018 0.002 0.005 0.035 0.004 Per Per Cent 12.00 none 12.00 1.75 8.00 none 0.94 8.00 0.34 13.60 none 13.60 0.49 —Per Cent Soluble Insoluble Total 0.002 0.024 0.002 0.003 0.008 0.018 0.006 0.020 hr. after dissolving 1:1 HCl. *Distilled immediately after dissolving 1:1 HCl. Iron Age, July 26, 1934 tion. Dilute 300 ml. with H,O and connect once the distilling ap- paratus, Fig. Then proceed with the distillation soluble nitrogen, titrating the unused portion the the receiving flask. considerable portion the total nitrogen will found this manner the insolubles, and some cases nearly all it, depending the amount titanium vanadium pres- ent. See Table No. III. The nitrogen ferrochromium determined like manner, both sol- uble and insoluble. Smaller weights are taken the high nitrogen ferro, may contain much 0.70 per cent nitrogen. Table are shown data the nitrogen determination 18-8 steels containing titanium. The last sam- ple shown also contained 1.12 per cent tungsten well 0.97 per cent Ti. The results parentheses the 0.45 per cent and the 0.97 per cent the steel equal volume con- centrated 1.20 sp.g. acid instead the 1:1 HCl. Very little increase the soluble nitrogen was obtained. The “Direct Determination” column shows results gotten simple solu- tion the steel the dilute acid. The soluble and the insoluble portions were transferred once and together the distillation flask. Then boiled and the ammonia formed distilled over the method described. The re- sults show that this boiling the al- kaline liquid only partially decom- posed the nitrides from the higher titanium steels. See also Table for similar experiments with vanadium stainless steels. The results given Table for the “Direct Determination” are lower than the “soluble nitrogen.” Further, the percentages “Insoluble Nitro- gen” are often out agreement. This condition also shown Table These variables not affect the “Total Nitrogen” but reveal that the compound sensitive oxidation the air. Hence, during filtering and washing with slight suction tion the nitrogen yielded and washed through into the filtrate and counted “Soluble Nitrogen.” Table there are shown data for miscellaneous steels steels containing molybdenum and colum- bium. can seen that molybde- num high 2.50 per cent low-carbon 18-8 grade does not render the nitrogen insoluble. evident from Table that the high nitrogen content comes largely ‘ B 0.48 ‘ tl so Palsy SO r 0.50 as eli do dis les fla tio: tec 0.015 hig hy | ith the ner the sol- rhts rro, per the cent 0.45 cent ving con- acid little was solu- acid. tions ether over re- al- igher for for lower rther, Nitro- This ble the the ion and and and ogen.” data steels colum- render the largely from the ferrochromium. This con- trary statement made ex- tended article published year two ago nitrogen steel which the author announced that nitrogen found steel was not coming from ferro- alloys. that time ferrochro- mium had been tested. year before the propaganda for the use high- nitrogen ferrochromium started, the writer found one lot ferrochromium contain 0.236 per cent nitrogen from random shipments. This was unusual that many tests were made attempt determine whether some other interfering element such sulphur might some way inter- fere. far interference other elements with the distillation method has been detected. That is, ele- ment occurring iron its alloys that could give nitrogen result higher than the true nitrogen content has been discovered. the following paragraph given the method for determining nitrogen high-copper, chromium, nickel, high- silicon corrosion-resisting steels which not contain titanium. Such steel dissolves very slowly and incomplete- dilute acids. Weigh gm. less millings into 500 ml. cone flask and add 100 ml. concentrated Table 6—18-8 With 2.50 Per Cent Molybdenum; 18-8 With 1.20 Per Cent Columbium and Miscellaneous Steels Per Cent Total 18-8 Steel, 0.06 per cent 2.50 per cent Mo... 0.957 0.001 0.058 0.002 0.058 18-8 Steel, 0.06 per cent 1.20 per cent 0.010 0.031 0.041 0.004 Low Carbon, per cent Chromium Iron ............ 0.070 per cent Nickel Steel 0.005 NOTE: The Nitrogen 0.009 per cent the columbium steel, and its nitride required three times long and twice much acid dissolve it. Table 7—Low-Carbon Ferrochromium Soluble Nitrogen 0.06 Per Cent Carbon ....... 0.057 0.057 0.12 Per Cent Carbon ...... 0.078 0.072 0.30 Per Cent Carbon ....... 0.236 0.233 0.11 Per Cent Carbon, High- Nitrogen, Ferrochromium. 0.600 0.590 HCl. Cover with inverted 125 ml. beaker and heat pan boil- ing water until the steel decomposed and the silicon and insolubles are floating about but still retain the form the drillings. decompose this combination weigh into the flask gm. NaF, and continue heat until silica gel appears. Then transfer this solution the distilling apparatus and finish usual distillation with 110 ml. per cent NaOH solu- tion. Run standard steel likewise get the blanks run blank with- out any steel and deduct. One steel this type highly alloyed with Cr, Ni, and gave the following re- sults: 0.031 per cent Nitrogen—5 grams 0.032 per cent Nitrogen—4 grams The nitrogen method checks very well with different amounts the sample. present, the black insolubles should decomposed with the fuming perchloric and sulphuric mixture. Metal Panels for Building Exteriors NEW method applying metal covering for buildings involving new principles design and construc- tion has been developed the Archi- tectural Metals Corpn., Hanna Build- ing, Cleveland, which has designated the Revocon system. The supporting member small semicircular section aluminum. This applied directly any structural framework other surface with helical drive screws ordinary bolts. This holding member erected horizontally and separated vertically smaller interlocking channel section the same material which slides laterally track pro- 3 we) — vided the horizontal holding mem- ber. This vertical channel section acts spacer for the horizontal section well backing for the vertical channel joint. Panels preformed metal are then pressed into the horizontal sections while the deformed vertical edges (Concluded Page 84) The Iron Age, July 26, 3 paper discusses the funda- mental nature the creep curve and also the probable effect upon strain hardening, an- nealing, age-hardening and other phenomena associated with stress- ing elevated temperatures. Utilizing published data ex- ample, the author points out how the information may made in. per inch 0.008 <x = a Cc oO o 0 a c | Effect Stres Equation service the designer who needs all can acquire help him solve the moment his problems laying out metal structures for operation high temperatures. The paper, which the accom- panying the major part, was pre- sented before the recent meeting Atlantic City the American Society for Testing Materials. 000 eformation Fig. National Physical Laboratory creep tests 0.30 per cent carbon cast steel. Annealed 800 (1470 F.), hr. Rough Annealed 550 (1020 F.), hr. Tested 400 (750 F.) (H. Tapsell and curves for several stresses constant temperature. Interpreting term creep rate taking materials elevated tempera- tures that the yield strength holds normal temperature. have one hand demand for reliable data which can used support the progress design toward higher temperatures; the other hand, find available materials exhibiting strange peculiarities which make difficult evaluate them any sim- ple method. The designer specifies estimated time-temperature cycle, desired service life limiting deformation, and asks what stress may use safely. this apparently simple question which has stimulated creep testing for over ten years. The answer complete only gives the allowable stress and cost per pound all available materials, since the economic side the problem also must considered. satisfy the need for design information necessary establish for each mate- rial the relations among the four variables—stress, strain, time, and temperature covering .the desired range for each variable. Significance and Limitations the Creep Rate typical creep curve obtained constant temperature and relatively high stress. elastic deformation results from the application the load after which creep proceeds gradually diminishing rate. inflection occurs after which the creep rate increases until the test specimen breaks. Curve similar for lower stress, the longer time pro- duce fracture resulting from lower creep rates. the stress further reduced, similar tests different and The locus points inflection, RS, not well known because tests are seldom carried beyond the line lor 4 - 0, Creep rat ‘ ing suf str all rat phe firs Ta \d L--=- it 16—The Iron Age, July 26, 1934 ata the her cle, ated cost lem isfy ate- four and ired Creep Tests for Use Metals High Temperatures MN. Available data indicate, how- ever, that the change from decreas- ing increasing creep rate occurs gradually diminishing value total deformation represented the the inflection points for curves and would require tests extremely long duration. the stress de- creases, the creep curve essentially straight line for longer period time approaches its inflection point. Theoretically, the rate continuously decreasing but actually the line may considered straight without serious error. The nature the curves such that may expect the increase rate equally slow after the inflection has been passed. Since actual work- ing stresses are usually below curve the assumption that the creep curve approaches straight line sufficiently accurate for many pur- poses. case, however, does the straight line pass through the origin. other words, its equation must have the form vot rather than vot. Any analysis fami- lies creep curves must make some allowance for the more rapid creep rate the initial stage. Creep Pure Metals—Strain Hardening and Annealing simplify the discussion creep phenomena, let consider that the curves Fig. represent tests pure metal, thus eliminating any pos- sibility solid solution precipita- tion constituents. For such ma- terial, the decreasing creep rate the first stage may attributed strain hardening which results from the gradually increasing deformation. were not for the softening effect temperature upon strain-hardened material, this might continue indefi- nitely the creep rate approached Studies the effect temperature upon strain-hardened material show McVETTY Mechanical Engineer, Research Laboratories, Westinghouse Electric Mfg. Co., East Pittsburgh, Pa. that the time required produce softening given temperature de- creases the amount deformation increases. This softening tends increase the creep rate. this ideal case, have two op- posing forces, one decreasing and the other increasing magnitude time goes on. should noted that separate studies both the strain- hardening and the annealing effects reveal discontinuities and cree 0.020 in. per inch Minimum Creep Vo, in. per inch per hr. Plastic Deformation, onstants & and Vo 8000 curve representing the net effect the two phenomena must have point the absence more complete explanation, may say that the form the typical creep curve greatly influenced not entirely con- trolled strain-hardening and an- nealing during the progress the test. considerations restrict our tests that portion the curves lying the left line MN, may use the reasoning out- lined above supply the dotted por- tions the curves representing the longer times found service. With- out some simplification this kind would practically impossible analyze the very complicated condi- tions actually existing and make allowance for necessary departures from the assumed simple relations. | | | | 000 Stress, per in. 3—National Physical Laboratory creep tests 0.39 per cent carbon forged steel. cooled. Rough machined. Annealed 550 (1020 F.). Tested 400 (750 F.). (H. Tapsell and Johnson). The Age, July 26, 1934—17 00020 ywer | tion, line must not inferred, however, that these departures are negligible. Creep Complex Alloys— Structural Changes Recent tests complex alloys have revealed many peculiarities. For example, impact tests before and after creep tests frequently show marked embrittlement the material due long exposure stress high temperature. This, itself, may enough prevent the use the material where good ductility con- sidered essential. For the purpose this discussion, more important consider the fact that the data obtained from the creep tests must have been influenced the gradual structural change within the material. The propriety extrapolating such test cover long service life extremely questionable. Another example recently came the attention the author which test showed continuous negative creep over period 2500 hr. This can only explained structural change causing decrease volume which completely masked the natural creep the direction the applied stress. One advantage test this kind lies its warning investi- gate structural stability. more dangerous case the one which structural change decreases all the creep rates series tests with- out showing negative creep. Special precautions are necessary all times avoid this possibility the data are used for design purposes. From these examples, apparent that creep tests are vitally affected structural changes during the prog- ress the test and their interpreta- tion affected also subsequent changes service. The lack structural stability non-ferrous materials has received considerable Recent investigations in- dicate that the alloys recommended for high-temperature applications are subject similar changes. This introduces metallurgical problem beyond the scope the present paper, 1P. Merica, Age Hardening Metals,” Transactions, Am. Inst. Mining and Metallurgical Engrs., Inst. Metals Di- vision, Vol. 99, (1932). Hensel and Larsen, “Age- Hardening Copper-Titanium Alloys,” Am. Inst. Mining and Metal- lurgical Engrs., Inst. Metals Division, Vol. Bailey and Roberts, “Test- ing Materials for Service High Tem- perature Steam Proceedings, Inst. Mechanical Vol. 122, 209 (1932). *Tentative Method Test for Long- Time (Creep) High-Temperature Tension Tests Metallic Materials; 1933 Book A.S.T.M. Tentative Standards, 1038. Method Test for Short- Time High-Temperature Tension Tests Metallic Book A.S.T.M. Tentative Standards, 1030. Iron Age, July 26, 1934 Plastic per cent Fig. 4—Stress-strain-time relations constant temperature. 0.30 per cent carbon cast steel—400 (750 F.). Based creep tests Tapsell and Johnson. but convenient here divide such changes into three broad classes. one, the hardness increases grad- ually maximum, and continued exposure stress and temperature produces further change. The effect this type change similar that strain- hardening. the condition ap- proximate stability finally reached not accompanied embrittlement other undesirable effects, the creep curve will merely show lower creep rates the early stage and longer time reach the inflection point. This offers difficulty interpre- tation. The second works the opposite direction, familiar example being the gradual spheroidization cemen- tite which has been studied Bailey and and others. long life desired and the allowable de- formation small, the stable condi- tion may obtained prior the test make the extrapolation the creep curves more reliable. evident, however, that may possible secure long service life before the spheroidization affects the strength seriously. This equivalent increase the annealing effect men- tioned for pure metal. Careful study individual case should allow the use higher stress than would permitted following hard and fast rules. The third type age-hardening involves gradual increase max- imum followed similar decrease condition approximate sta- bility. Alloys showing this phenome- non during the creep test give results particularly difficult This does not prevent their use, how- ever, because usually possible apply stabilizing treatment prior the creep tests bring them into approximate equilibrium and service conditions. Any attempt take advantage temporary im- provement creep properties due this type should avoided, allowable deformation the criterion safety. Proposed Method for Correlating Creep Data has been stated that the designer requires knowledge the relations among the strain, time and temperature. The first two are covered the conven- tional short-time tension the first three the creep and the fourth conducting short-time ten- sion and creep tests suitably chosen temperatures. show the possibilities such method, use will made creep unde for prio: For data Stren and Stre: Lb. 25°76 29,12¢ ard Plastic Deformation, per cent Fig. 5—Stress-strain-time relations constant temperature. 0.39 per cent carbon forged steel—400 (750 F.). Based creep tests Tapsell and Johnson. The work was done the National Physical Laboratory under the most favorable conditions for securing reliable data. The two materials were carefully heat treated prior the tests ensure stability. For the purpose this analysis, the data Table have been taken from their report. *H. Tapsell and Johnson, “The Strength High Temperatures Cast and Forged Steel Used for Turbine Construction,” Special Report No. 17, De- partment Scientific and Industrial Re- Search (London) (1931). McVetty, “Working Stresses for High-Temperature Service,” Mechanical Engineering, March, 1934, 149. Following the method previously each creep curve may replaced, for the purpose extra- polation, straight line having the equation: where final plastic strain creep, in. per inch, in. per inch, in. per inch per hour, and Since the values and are TABLE I.—CREEP DATA CAST AND FORGED STEEL (TAPSELL AND JOHNSON) Final Minimum Stress, Strain, Creep Rate, Lb. per In. Time, vo, In, per Sq. In. per In. Hr. In. per Hr. Initial Elas- tic Plus Plastic Initial Strain, Elastic Plastic Strain, Strain, In. vot, In. In. In. per In. per In. per In. per In. 0.30 CARBON STEEL 400 (750 F.) 35,840 0.0368 960 0.0000125 0.01200 0.0248 0.0014 0.0234 33,600 0.0267 720 0.0000072 0.005184 0.0215 0.0013 0.0202 31,360 0.0209 864 0.0000050 0.004320 0.0166 0.0012 0.0154 0.0163 1,368 0.0000030 0.004104 0.0122 0.0011 0.0111 25,760 0.0072 912 0.00000148 0.001350 0.00585 0.0010 0.00485 22,400 0.0036 1,656 0.000000375 0.000621 0.00298 0.00087 0.00211 0.39 CENT CARBON ForGED STEEL 400 (750 F.) 42,560 0.0229 504 0.00001230 0.0061992 0.0167 0.00174 0.01496 35,840 0.0140 1,080 0.00000268 0.0028944 0.0075 0.00146 0.00604 29,120 0.0055 4,128 0.000000375 0.0015480 0.0040 0.00119 0.00281 functions the applied stress, they may plotted shown Figs. and would very desirable have tests lower stresses, but their absence permissible extend the curves the origin. facilitate the reading values the two variables low stresses, each curve has been replotted larger the same sheet with values indicated along the curves. from these curves for the desired compute the creep the end various time intervals. This permits the plotting the estimated creep the end years, years, etc., form which represents the effect time upon the stress-strain curves shown Figs. and These charts give the designer the desired information the relations among the variables stress, strain and time for the given temperature. They assume that inflections will not occur within the service life the material deformations less than per cent and that the creep curve low stresses may extrapolated along the final tangent. They take into account the initial plastic deformation obtained extrapolating the final tangent zero time. If, for example, the designer wishes know what stress may use keep the plastic deformation within the limit 0.5 per cent years, reads from Fig. for the cast and from Fig. for the forged steel stress 10,500 lb. per Sim- ilar charts for other materials allow comparisons the basis allowable deformation and service life. This method comparison of- fered tentative The difficulty making corrections for the effects changes the many variables involved fully realized. If, however, all available data were reduced this form and compared, inconsistencies would revealed and the reliability all the data improved correlation this kind that the max- imum value may obtained from existing data. mapping out any program creep tests, economic considerations demand that their number and dura- tion reduced absolute mini- mum. the method here suggested, possible form some estimate new alloy few two creep tests. this preliminary study encouraging, the accuracy the work may improved more tests. The Age, July 26, 1934—19 000 ing ase ne- ilts ret. ‘ior nto ner ons ess, ren- the the sen never was circus strong man, but gives that impression lifting two beer barrels with ERE impromptu test welded steel two fingers. (Empty ones, course.) The barrels are structural construction. oil explosion fol- made aluminum and weigh only each lowed fire the Spring Perch Co., Lackawanna, Y., destroyed the structure without causing the failure single weld. The welds were made ERE strenuous load test being applied the body ten-passenger Boeing air liner. Fifty-two tons lead were re- quired break the plane. This was more than per cent overload. These new passenger planes are about twice strong the previous ones that they are replacing the air lines the arc ment. and the the arc process with Lincoln Electric Co. equip- ment. Twisted and bent the terrific explosion and the heat the flames, trusses and bar joists the one-story mill building formed contorted mass steel upon the former factory floor ELOW the first ever built, back the after two-year tour Europe. the property the Edward Budd Manufacturing Co., who had built three years ago demonstrate the practicability the shot-weld process applied stainless steel. has the same type construction the Burlington . HEVROLET now has assembly line for bum, ers its Holbrook Avenue, Detroit, plant More than 7000 complete bumpers are assembled here each working illustration shows the final assembly end the line URNING “coal wrapped paper, utilizing gas fuel desired, this new air conditioner attains heat efficiency per cent. heats, humidifies, cleans the and made from Armco products the air winter and cools and de- eby > Running hydrogen for making synthetic ammonia, Prof. Chechin, the Soviet Nitrogen Institute, posed that the blast furnace used able for ammonia synthesis. seeking new sources cheap This proposal introduces impor- tant change the ordinary blast-fur- nace process pig iron production and also the construction blast- blast stoves and air-blowers, which consequently lowers the installation costs blast-furnace plants. More- over, the new method producing gas-mixture for the synthesis am- monia simplifies the construction the ammonia plants combining the synthetic ammonia and iron-making plants into one. Synthetic ammonia may duced either from pure components (nitrogen and hydrogen) mixing them the necessary volumetric pro- portion, 1:3, from prepared gas-mixture which both components are already mixed proportion cor- responding 1:3. order obtain such gas-mixture water-gas usual- made use the aid the car- bon monoxide conversion method with subsequent removal CO, and the remaining. Any besides water-gas may converted into hydrogen the aid steam, contains sufficient quantity CO. The utility any gas-mixture subjected conversion for the pur- pose preparing synthetic ammonia from later may determined the volumetric ratio gas-mixture constitutents, that is, obtain gas-mixture having composition equal 3H, from the ordinary blast-furnace gas, necessary either add the latter proper quantity hydrogen ob- tained from some other source re- duce its nitrogen content. The blast- furnace process carried out means cold oxygen enriched blast in- stead ordinary hot-air blast offers favorable conditions for the ac- complishment the desired end. 22—The Iron Age, July 26, 1934 SUSLOV Metallurgical Engineer, Research Institute, Theoretical metallurgical calcula- tions have shown that using blast containing from per cent oxygen for operating the blast fur- nace gas mixiure suitable com- position may realized. the oxy- gen content the blast rises per cent more than the normal quantity oxygen the air, which equal about per cent, the combustion temperature coke rises about deg. When there per cent oxygen the blast the theoretical combustion temperature the coke equal about 2150 deg. (3900 deg. F.). reach such temperature the hearth the furnace with hot blast would necessary preheat the latter 800 deg. the hot- blast stoves. Thus, raising the quantity oxygen the blast more than per cent, preliminary preheating blast and consequently expensive hot-blast stoves may When the oxygen content the blast equal per cent, the theoretical coke combustion temperature the hearth the furnace reaches 3200 deg. (5800 deg. F.), which too high, exceeds the melting point the best refractory materials used for the furnace lining. Some metallurgists claim im- possible provide normal blast- furnace process using blast con- taining per cent oxygen. But, the other hand, possible regulate the temperature the hearth materials CO, and into the coke combustion zone, which dissociate high temperature, thus absorbing the excessive heat and lowering the temperature the hearth. Laboratory tests carried out the Nitrogen Institute showed the possi- bility making synthetic ammonia, the aid blast-furnace process carried out oxygen enriched blast, and was decided perform smelting tests semi-commercial Furnace for scale. This was done under the super- vision Professor Chechin and col- laborators small blas