The Iron Age 1945-11-15: Vol 156 Iss 20

VAN DEVENTER President and Editorial Directer BAUR Vice-President General Manoger LEONARD Assistant General Manager HAYES Advertising Manager JOHNSON, Monager Reader Service and Research BAUR, Production Manager CLEARY, Technical Research and Promotion Manager Executive Offices Chestnut and Séth Sts. Philadelphia 39, Pa., U.S.A. Editorial and Advertising Offices 100 East 42nd St., New York 17, N.Y.,U.S.A. Regional Business Monagers New York New York 100 East 42nd St. 100 East 42nd St. ROBERT BLAIR GIBBS Cleveland Pittsburgh Guardian 428 Park Bidg. Philadelphia Chicago Chilton Bidg. 1134 Otis Bidg. PEIRCE LEWIS WARREN Detroit Hartford Conn. 1310 Woodward Ave. Box RAYMOND KAY Los Angeles 2420 Ave. ° ° Owned and Published CHILTON COMPANY OFFICERS AND DIRECTORS MUSSELMAN, JOS. HILDRETH, President GEORGE GRIFFITHS Vice-President EVERIT TERHUNE Vice-President VAN DEVENTER Vice-President BAUR Vice-President Vice-President JULIAN CHASE Vice-President WILLIAM BARBER, Treasurer JOHN BLAIR MOFFETT, Secretory BUZBY HARRY DUFFY THOMAS KANE CHARLES HEALE WILLIAM VALLAR, Asst. Treas. ° ° Chilton Editorial Boord PAUL WOOTON Washington Member, Audit Circulation Member, Associated Business lished every Thursdoy. Subscription Price North America, South and Possessions, $8; Foreign, per yeor. | 1945, by Chilten Company (!ne.) | | | | | The IRON AGE Vol. 156, No. November 15, 1945 Editorial Wages and Hours Steel Technical Articles Precision Casting With Plastic Patterns Corrosion Performance Blackplate Cans Surface Finishing Beryllium Copper Spectroscopic Control Tropenas Converter Welding Galvanized Steel Behavior Charge Material the Cupola Moving the Pembroke Blast Furnace Porosity Navy and Metals and Red Brasses Segregation Rimming Steel Ingot British Alloy Specifications Bethlehem Centralizes Bar Mills New Equipment Features News Front Assembly Line Washington West Coast European Letter Personals and Obituaries Dear Editor This Industrial Week News Industry News and Markets Machine Tool Developments Nonferrous Market News and Prices Iron and Steel Scrap News and Prices Finished and Semifinished Steel Prices Alloy Steel Prices Fabricated Steel Products Prices Warehouse Steel and Pig Iron Prices Ferroalloy Prices Comparison Prices Week and Year Wartime Aluminum Expansion and Controls Pittsburgh ASM Technical Session Factory Employment Buffalo United Engineering Trustees Elect Oregon Coals for Carbon Production Ratings for Foundries Moved Termination Stocks Increase Requests Release Enemy Data Earnings Reports Urge Withdrawal Controls Foundries Construction Steel Awards and Inquiries Scrap Institute Elects Officers ASM Elects Officers Index Advertisers 297-8 H | 102 104 107 126-7 128-9 130 131 133 134 135 136 156 158 160 162 162 164 166 168 172 178 185 188 ° ALLOY STEELS PLATES How Ryerson Protect Your Production Every Department Served When your shipment Ryerson alloy steels arrives, complete test data comes with them—data that enables engineers and designers call for the physical properties listed, with confidence that they can secured—that furnishes heat treaters with guide sure, accurate results and provides detailed record for your purchasing executive. part the Ryerson Certified Steel Plan, this data developed from actual laboratory tests. addition mill tests for chemical analysis and physical characteristics, Ryerson subjects sam- ples from each alloy heat four end-quench hard- enability tests. From hardness readings the test samples interpret obtainable physical properties for rounds the as-quenched condition and when quenched and drawn 1000°, 1100° and 1200° This test data comes with alloys which are identified heat symbol well color marking. And make doubly certain that you get the right steel Ryerson checks against mixed ship- ments spark testing all alloys stock. Ryerson alloy service costs you nothing extra. protects your products and production. saves time and money. furnished Ryerson Steel-Service Plants, each located major in- dustrial area. The Ryerson alloy plan explained detail our booklet Hardenabil- you did not receive copy write today. And get touch with your nearest Ryerson plant «when you need alloy steel from stock. JOSEPH RYERSON SON, INC. Steel- Service Plants: Chicago, Milwaukee, Detroit, St. Cincinnati, Cleveland, Pittsburgh, Philadelphia, Buffalo, New York, Boston. RYERSON STEEL BARS MACHINERY ALLEGHENY STAINLESS 50—THE IRON AGE, November 15, 1945 TOOL STEEL SCREW STOCK TUBING PIPE Pre Edito News Mach if i | { | | | | ESTABLISHED November 1945 VAN DEVENTER President and Editorial Director BAUR Vice-President and General Manager ° ° Editorial Machine Tool Editor...H. LINSLEY Associate Editors WINTERS ALBIN JOHN ANTHONY BARMASEL Editorial Assistants SCHIEN SPEAR Foreign Editors Canada (Contrib.)......F. Sanderson Regional News and Technical Editors LLOYD Pittsburgh 428 Park Bidg. POST Chicago 1134 Otis Bidg. MOFFETT EUGENE HARDY ANSBORO Washington National Press LLOYD Cleveland 1016 Guardian BRAMS DETROIT 7310 Woodward Ave. OSGOOD MURDOCK WORTH HALE San Francisco Market St. Editorial Correspondents ROBERT Cincinnati DEAN Buffalo FRAZAR Boston HUGH SHARP Milwaukee RAYMOND KAY Los Angeles JOHN McCUNE Birmingham ROY EDMONDS St. Louls JAMES DOUGLAS Seattle ARS Wages and Hours Steel one basic fact that must considered management, labor and the public connection with this present postwar wage- hour controversy. And that that both profits and wages hinge productivity. other words, you cannot have more than you make. Most would like shut our eyes and ears this cold but very real fact and think that can pattern new world without re- course arithmetic. gains industry, and indeed any field effort, come from increased productivity per hour. You cannot take out any hour more than you put into it. The average increase industrial productivity per hour this country has been approximately pct per year. This means that can double our standard living every fifty years. Popular notions about the amount have increased productivity per hour during the war are erroneous. the steel industry, for ex- ample, the increase per hour per hourly-paid wage earner has been 9.5 between 1939 and 1944 inclusive little less than pct. Against this, the earnings per hour hourly-paid wage earners the industry were increased 38.8 pct during this period over four times much productivity. true that annual production increased faster than this but that came from longer hours and more producers. These basic facts must kept mind considering present day wage demands. matter how much would like see wage pur- chasing power increased, cannot faster rate than that productivity. The best way for labor and management the steel and automo- bile industries get together through common sense bargaining with- out bludgeoning. The best way keep them together after they get together see that both sides live the bargain made. However, since steel and the automobile industry are such predomi- nant American pace-setters, any bargain made must the best interest all labor and all the public and not such elevate any minority group the detriment other minorities the Thus the pattern established must one that falls within the limits liquid economy and must capable being financed out earnings and not from debt nonrecurrent savings. Management both industries fully aware the economic value high wages and has fully demonstrated this payroll performance. realizes its obligations continue pass labor, stockholders and the plant equipment vital both, their proper shares future increased earnings they develop through increased But management cannot count its chickens before they are hatched nor can it, public interest, literally “shoot the works” the gamble that four years wealth destruction through war can boost all upstairs into higher living level. Future productivity and future efficiency alone will determire that. let’s get work and find out how much larger pie can bake before attempt slice it. News-Markets Editor CAMPBELL | VAN CAMP MUNZER SCHIMKO ! 52—THE IRON AGE, November 1945 a HOW DEVELOP LOWER DELIVERED COSTS STEEL Steel low cost large tonnage product when compared with other metals. But the net cost delivered alongside your machinery and equipment varies greatly different plants depending upon the mill methods packing and the manufacturers’ methods receiving and handling. Inland metallurgists control quality from the ore the finished product but the preservation that quality still another factor final machine side delivery. Inland shipping experts prepare the steel with care and pack for safe arrival and quick economical receiving and handling. But there are many types equipment that may Here Cost Factor Worth Checking STEEL used receiving and handling that important ‘that the shipping and receiving methods dovetail order secure the lowest possible costs. develop this teamwork between us, often advisable compare notes. Inland shippers are available consult with you any time and make recommendations toward the lowering your final machine side cost steel. Inland Steel Company, South Dearborn Street. Chicago Sales Offices: Cincinnati, Indianapolis, Kansas City, Milwaukee, New York. St. Louis, St. Paul. Principal Products: Bars turals Plates Sheets Strip Tin Plate Floor Plate Piling Reinforcing Bars Rails Track Accessories i a ‘ € evelop ble you steel. Street. York, Struc- Floor Track NEWSFRONT Nov. 13, 1945 precision casting pilot plant operating the International Nickel Co's Bayonne foundry turning out high nickel alloy castings Monel, Inconel and nickel the rate 500 per week. Castings weighing each are now being produced. Radar soon used train protective control mechanism. The Sperry Gyroscope Co. has recently established new division handle this development which most railroads are said interested. The most useful steels are about adopted the SAE into its standard steel classification for postwar use. these, 8600 and 8700 differ only molybdenum content which some overlapping. Some consumers who have placed orders for both steels order compare claim have discovered that the producer melted both steels from single composition, holding molybdenum the overlapping range. new welding rod has been developed for making machinable welds cast iron. Corrosion studies lacquered blackplate used ends food cans show that plate superior hot-rolled plate. Phosphating does not reduce the rate internal corrosion and may even increase adherence the quer the surface the plate not good. Substitution blackplate for tinplate ends does not affect the color and flavor vegetdbles the lacquer protection average efficiency. The stitution much less satisfactory with fruits. Application electroplating finishes beryllium copper eliminates ing the alloy under normal conditions and the formation verdigris when parts become contaminated with fatty acids, polishing compounds acid atmospheres high humidity. For galvanized steel welds highest tensile strength, spot welding machines should set for short sharp heat with mechanical pressure applied soon the electrode comes down. short sharp heat minimizes loss through volatilization and does not allow enough time for the formation diffusion alloy inside the weld. Dominant factors governing the manner descent materials charged into cupola are the shape and size the pieces the charge and not its original relative position, British investigations indicate. Rate complete melting metal pieces also governed the main and weight well their relative melting temperatures. Production Mercury cars has begun Dearborn and will follow Chicago and Edgewater. Mechanical improvements include tri-alloy bearings, crankcase ventilation, improved oil pump, aluminum pistons and interchangeable cylinder heads. The British temporary housing program involves 123,000 units eight con- struction types. One type employs asbestos siding over steel framework. Another prefabricated Other constructions employ asbestos and timber framing, reinforced concrete, construction, and there are relatively small numbers and steel framework designs. The long term British plan million permanent homes constructed over the next yr. for the first cash sale steel foreign governments since the end have been concluded million deal with the French and Russian governments. new Boeing long-range carrier fighter equipped with internal bomb-| bay and adaptable service torpedo plane has been unveiled. fighter, the plane has top speed 425 mph with military power, excess 450 mph with war emergency power. 3 ee > x 4 ‘ | | F : 4 a 5 Precision Casting With Plastic Patterns Use injection molded polystyrene patterns overcomes the problems perishability found with wax patterns while affording high dimensional accuracy, smooth finish and reproducibility long runs. accuracy the lost wax pre- cision casting process mated with reproducibility longer produc- tion runs has posed multitude problems castings manufacturers. These problems have sired intensive research into pattern materials obvi- ating many these difficulties, with polystyrene, and more recently other styrol resins, heading the procession. Precision casting the Illinois Pre- cise Casting Co., 613 West 16th St., Chicago 16, which Leonard Dean research and development engineer, has demonstrated the virtues polystyrene patterns mass pre- cision castings production. Inherent virtues this thermoplastic can gleaned from the textbooks (see ac- companying table). Polystyrene supplied under vari- ous trade names several companies including Bakelite Corp., the Dow Chemical Co., Monsanto Chemical Co., Catalin Corp., Union Carbide Car- bon Corp., and American Phenolic Corp. Another styrol resin, Styramic, produced Monsanto, figures cur- rent pattern experiments. Polystyrene sells for about 27¢ per Chicago. Tolerances +0.0005 in. have been achieved small parts production contracts, with tolerances +0.002 polystyrene patterns tolerances can held close +0.0005 in. small parts. The specification below for this square sec- tion indicates the degree dimensional accuracy obtainable with these patterns. Grain run this way “within Q0005 +0.000 Holes after plating All other frac. dim. 54—THE IRON AGE, November 15, 1945 deep Tap #2-64 NF2- deep Remove burrs Zinc plate 0.0002-0.0003 Th. ° ° CHARLES POST Chicago Editor, Iron common larger castings. (See Fig. 1.) Production tolerances with wax usually range from +0.002 in. +0.003 in. Shrinkage, although varying with the part being produced, said cause fewer headaches pattern de- sign. Perishability polystyrene pat- terns practically nil. Kid-glove handling, necessary for wax patterns entirely reducing scrap and saving time the production process. Completed war patterns com- monly are individually placed with great care prior assembly pat- terns for investment. Polystyrene patterns may tossed into box they come from the injection molding machine. Care also must taken assembling wax patterns for spruing avoid bending breaking while polystyrene patterns will stand con- siderable man-handling with resultant time saving factors. This hardiness also eliminates chipping which has constituted production obstacle with wax. Intricate coring simplified. Close temperature and humidity control necessary maintain close tolerances with wax and prevent warpage virtually eliminated with polystyrene. Polystyrene finds its forte longer production runs which can achieved with maintenance dimensional accu- racy due part the use steel dies injection molding the patterns. Softer metals often used molding wax patterns have shorter die life. Ease handling evacuating pat- terns from the molds prior casting also set forth polystyrene plus point. Cost setting for production polystyrene patterns limits their field longer production runs and parts requiring extreme dimensional accu- racy. Heavy capital charges are in- volved injection molding machines necessary produce the patterns. Sinking steel molding dies main- tain dimensional accuracies required | ski alo tol tic Ss RIGHT 2—Typical assort- ment parts cast Precise Casting Co. using polystyrene patterns. ° LOWER RIGHT Operator rene pattern from two die HPM injection molding press. Note extractor and ejec- tor pins. intricate and expensive problem design and technique requiring skilled tool and die makers rather than basement mechanics. This fact alone limits polystyrene patterns parts intricate design and close tolerance those scheduled for long production runs. Although Precise Casting Co. has made produc- tion runs low 200 pieces intricate, close-tolerance parts, elimi- nating heavy machining costs, mini- mum production runs normally are about 5000 pieces. short runs, the company has used bronze injection molding dies instead steel. Longest production run date any one part has been 100,000 pieces but schedules are pending for several times this amount. Experimental runs have been made such small castings phonograph 4—Pouring investment material vibrating tables eliminates porosity and assures firm molding investment around pattern. 7 needles. The upper limit the cast- ings produced about From one parts have been produced single 3-in. mold. The company developing casting machine and mold capable casting steel, raising the maximum parts per cast correspondingly. Chemical analysis has been held close limit with alloys sometimes added the melts tenths grams. Grain structure the casting steel has been gratifying. Excepting precious metals and mag- THE IRON AGE, November 15, love tion pat- rene ling ling hile has nesium, casting materials have run the metallurgical gamut. copper, brass, bronze, iron, 303, 304, 403, 410, 416, 25-12, 18-8 stainless steels, Alnico, Colmonoy, Stellite, 1020, 1050, 4140, 4150, 8630, 8617, tool and die steels various types, gear steels and va- nadium steel are among metals cast. Emphasis nonmachinable alloys. Close production control pro- duction runs preceded pilot trials relied maintain standards. Laboratory and production equipment Illinois Precise comprises HPM injection molding machine, centri- fugal casting machines, capable handling together 150 molds hr, one and five induction melting units, along with accessory production equipment. The firm main- tains its own die shop because the difficulty procuring commercial dies suitable for injection molding pat- terns. casting machine end casting cycle showing, the flask horizontal position adjacent the crucible emptied steel. beginning the cycle the crucible withdrawn the right and induction coil placed over it. The coil then raised and the crucible thrust the left adjacent the flask. Cen- trifugal action throws metal from the crucible into the mold cavity the flask. Opera- tion automatic. Other dimensional accuracies achieved include class threads, holes 0.020 in., and sur- Production has been dominated ordnance parts including parts for the carbine, cocking forks, sight leaf slides for the cal machine gun, torpedo parts, land and sea mine parts and rocket parts. Civilian prod- ucts production and representing possible fields include small die inserts, gun parts, radio and phonograph parts, small gears, sewing machine, typewriter and adding ma- chine parts, and Tom Thumb intri- cacies for all types equipment (fig. 2). machine and punch press parts are not considered field. Machining Master Patterns The casting production cycle with polystyrene patterns forks from the lost wax path the initial stages, re- joining following evacuation the pattern from the Use hard steel injection molding dies makes impossible produce master mold direct from the part produced sometimes done with soft metal master molds used the lost wax process. simpler parts with liberal tolerances often possible ma- chine master polystyrene pattern direct from polystyrene bar stock then precision cast steel die cavities. High machinability polystyrene Physical Properties Molded Polystyrene Physical Properties Specific gravity 1.07 Tensile strength (psi) Flexural strength (psi) Modulus elasticity (psi) 5500 6500 6500 7000 0.20 0.35 0.6 6500 7500 14,000 19,000 Shrinkage 0.005 0.002 0.008 makes this possible. For the more in- (318 hr, disk) 0.05 pet tricate pieces, molding dies must designed and sunk using blueprints coefficient linear expansion (per 1°C) Heat resistance, 150° 170°F depending upon particular piece. starting point. With few excep tions, the general principles 56—THE IRON AGE, November 15, 1945 et pe prior osse™ | pory® | | at run minum, iron, 416, Alnico, 4140, Steels ind va- cast. alloys, pro- trials ipment HPM centri- ble hr, luction the dies pat- sur- ted ‘or the sight gun, mine enting tools, and ewing ma- intri- (fig. press fertile with the the hard kes mold duced metal wax iberal ma- attern vities. yrene in- ats ing molding die design and construc- tion prevail. provide unimpeded material flow around runner, channels are used. Direct, short and highly polished run- ners reduce flow resistance the minimum. Sharp turns are undesir- able. taper from heavy cross- section near the sprue light sec- tion the gate general. Care must taken have large enough runners for the area served prevent harden- ing polystyrene the runners cut- ting off pressure remote cavities 7—Late model precision casting machines Illinois Precise Casting Co. with generator equipment ground. One gener- ator operates two machines. and causing shrinkage during the cooling period the piece. Gating must developed meet the flow requirements the individual piece. The basic point difference from die making for run-of-the-mine injec- tion molded plastic parts that the extreme accuracy required for preci- sion cast pieces necessitates far more accurate dies and provision for sim- ple corrections beyond the range predictability. More less unpredictable shrinkage —and sometimes expansion—charac- teristics polystyrene pattern sec- tions make risky attempt one- piece die for complicated patterns. Therefore, the die cavity made necessary correct dimensions new insert may set without the cost constructing whole new die. Plating dies has proved un- satisfactory most instances, par- ticularly corners where sharp accurate contour necessary. Nearly all production runs must preceded laboratory pilot produc- tion, sometimes lengthy, with con- siderable amount cut-and-try. This emphasizes the necessity well equipped laboratory sufficient financial stability absorb experi- mental costs. Illinois Precise utilizes HPM hori- zontal injection molding machines for pattern production. The operating cycle these machines, which are common use plastics molding, starts with the loading pulverized polys- tyrene into hopper which agitated move gravity small quantities the material into feed cylinder required. the injection stroke starts, hydraulically actuated plunger forces fresh material into the heating cylinder where melted, and the same time displaces melted material; softened the cylinder heat and pressure, through orifice into the tightly locked two-section mold cavity form the piece. The pressure held long necessary cool harden the material the mold, the plunger then moving back allow new raw material drop into the feed cylinder. With the pres- sure relieved, the mold unlocked and movable section moves away from fixed section. The sprue dis- connects from the melted material, taking hardened material the ori- fice and leaving soft material the point which pulls away. Ejector pins push the molded piece completely free from the mold, after which the press operator places recep- tacle for trimming, necessary (fig. 3). Heating the heating cylinder electrically heated oil with vari- able temperature control. maintain dimensional accuracy the patterns die temperature dur- ing molding must evenly held. Illinois Precision Casting Co. has ex- perienced some difficulty patterns furnished from outside sources from the variation patterns injection molded during the early part the day, with cold die, and those made later during the work period after the die has heated. Operators THE IRON AGE, November 1945—57 x ~ 34 Received Received 1000X Annealed 100X Annealed 1000X a Received, Quenched and Received, Quenched and Tempered 100X Tempered 1000X * F > Annealed, Quenched and Tempered 100X Annealed, Quenched and Tempered 1000X 8—Microstructure SAE 4140 Steel precision cast using polystyrene patterns. Structures are shown as-cast and heat treatment. 58—THE IRON AGE, November 15, 1945 not familiar with the accuracy neces- sary for precision casting often will suddenly cool die after has heated causing sharp variation pat- tern dimension. Temperature and pressure under which polystyrene injected into the die cavity also must carefully watched. Assembly individual patterns in- cluster casting formation at- tachment shallow plug base button corresponds that used with wax patterns. Attachment polysty- rene patterns achieved moisten- ing the tips with carbon tetrachloride, polystyrene solvent, “welding” them with bunsen burners. with wax patterns, when the polystyrene sprue button attached, each assembled pattern placed rubber base, flask placed over it, and investment poured (see fig. 4). After the in- vestment material has solidified, but prior curing, the rubber base re- moved. Little flash remains trimmed after injection molding patterns. Flashing reground for use with new material feeding the injection mold- ing machine. Techniques investment merge essentially with those the lost wax process. Stainless steel flasks, fig. are used hold the investment. with most precision casting manufacture the binder used the realm restricted information. One basic formula used with various modifications. general, any binder used for wax pattern investment will satisfactory for polystyrene, al- though the reverse does not hold true. Polystyrene said less chemi- cally reactive than wax. (Polystyrene dissolved attacked styrene, benzene, toluene, dioxane, ethyl acet- ate, ethyl benzene, chloride, car- bon tetrachloride, turpentine, gasoline and certain patented solvents. unaffected acetic acid, formic acid, butanol, octyl alcohol, pct solution sodium hydroxide, pct solution potassium hydroxide, ethylene dia- mine, salt water, bleaching solution, photographic chemicals and most fats, animal and vegetable oils.) From the standpoint burning out patterns important that the binder heat resistant that sharp contours may maintained. Again, the importance laboratory runs before production emphasized. Smoothness pattern surfaces has eliminated coating patterns the Illinois Precise Casting Co. production cycle. Investment curing temperatures range from 90° 200° and cur- ing times from days. Batch type gas-fired ovens are employed. Polystyrene burns out 750° but mold 600° The rang shap diam can) pour 2000 the { 7 trie for tin the sti pl: Ce in molds sometimes are brought down 600° before pouring the metal. The upper limits the temperature range are dependent the size and shape the pattern (length cavity, diameter cavity, and length mold can) and the type metal poured, but the upper limit about 2000° Burn out time dependent hardness and grain size desired the part, tolerances, surfaces and cores, and ranges from hr. These factors control because pouring the metal done immediately after burning out the polystyrene pattern without cooling the molds room temperature. Batch type gas-fired furnaces are also used for the burn out. Factors metal pouring tem- peratures are, course, the same though wax patterns had been used and grain structures, tolerances, sur- face and type metal controlled. Ecco high frequency induction melt- ing unit with automatic temperature control employed for melting. Automatic horizontal centrifugal cast- ing machines the company’s own design but standard principle are employed (figs. and 7). reclamation made plastic after melted out nor mold ma- terial reclaimed. Corrosion Performance Blackplate Cans wartime and current scarcity tin has made necessary seek methods economizing the use tinplate the canning indus- tries. Wide investigations have been made the corrosion blackplate when substituted for tinplate cans for fruit and vegetables, and study Adams and Dickenson paper recently presented before the Iron Steel Institute, London. was learned early stage that the substitution blackplate for tinplate over the entire can was im- practicable because difficulties as- sociated with the soldering the side seams blackplate. Efforts were therefore confined the use lac- quered blackplate place tinplate ends cans. Even this partial sub- stitution results saving tin- for the small and medium sizes cans commonly used for vegetables and fruits. The points noted the study were the rate formation hydro- gen the cans, the rate dissolu- tion iron and tin and the effect the substitution the color and flavor the contents. The main con- clusions reached were follows: (1) Cold-reduced plate superior hot-rolled plate blackplate ends covered with single roller-coating lacquer. Phosphating does not re- duce the rate internal corrosion and may increase the lacquer adheres indifferently the surface the plate. (2) Types lacquer vary the protection they afford. Lacquered blackplate ends, with further dipped coating lacquer, give results which are comparable with standard quered plain tinplate ends. (3) The rates attack the var- ious fruits and vegetables black- plate ends differ greatly and are high- est for the acid fruits and beetroot. (4) The substitution blackplate for tinplate ends does not affect the color and flavor vegetables the lacquer protection average effi- ciency. The situation much less ‘satisfactory with fruits. (5) The substitution blackplate for the bodies cans well the ends impracticable for general use, but the effect the storage proper- ties very similar that observed cans with tinplate bodies and black- plate ends. these tests the weight the lacquer film the phosphated plate was the same that the untreat- blackplate. Better results were obtained when heavier films were used with phosphated plate. One the chief risks substi- tuting lacquered blackplate for tin- plate increase the rate formation hydrogen the cans. The rate corrosion tinplate cans filled with vegetables very slow compared with that cans filled with fruits, and was necessary use different experimental techniques for the two classes products. With fruits the cans were merely held store until the evolution hydrogen overcame the partial vacuum initially present and then built sufficient pressure for the cans dome out- wards and become “hydrogen swells.” Results comparative tests fruits were generally ready after months’ storage. The slower formation hydrogen canned vegetables made neces- sary measure very small reductions vacuum the sealed cans. This was done recording the average change depression the centre the ends below the level the hori- zontal channel adjacent the end seams. The measurement was made means specially constructed each lot and repeated monthly intervals. Metallic contamination the con- tents important from standpoint and from the tendency tin iron cause discoloration some vegetables. also useful indication the type corrosion which has occurred. These tests also show that the iron contents vegetables packed cans with blackplate ends protected efficient lacquer film are not appreci- ably different from those cans with tinplate ends. The tin contents appear lacquering the blackplate ends. The use blackplate place tinplate ends did not affect the color the vegetables appreciably, except far the beetroots discolored proportion their iron content. Specks iron sulphide were noted some the cans peas, swedes, and carrots, particularly those with single-lacquered ends. Apart from metallic flavor the beetroot with high iron content, there was ap- parent difference flavor between the vegetables from blackplate and those from tinplate cans. THE IRON AGE, November vill ted at- ind ust in- at- ith ty- de, ith led se, in- ns. ld- ler al- ni- ne, id, ia- ts, res Surface Finishing Beryllium Copper Although regarded corrosion-resisting alloy under normal usage, beryllium copper components benefit when given electro- plate finishes satisfactory for other copper-rich alloys. Details numerous acid solutions for removing oxide scale are given with particulars sulphuric acid treatment followed acid dichromate solution. Cleaning specifically for electroplating also discussed. beryllium copper alloy can precipitation-hard- ened controlled thermal treatment, eminently suitable for the production tiny components intricate shape which the final shaped article has possess par- ticular qualities hardness spring- iness. Under normal conditions indoor usage and exposure, beryllium copper may regarded cor- rosion resisting nonferrous alloy, least equal copper itself. But special consideration would have given relation any specially corroding atmosphere. Methods for cleaning and electroplate finishing beryllium copper components included herein have been published the British journal, Metal Treatment. beryllium copper will gradually stain and darken, finally becoming black under normal conditions just the same way copper does. Likewise, will become green with verdigris contaminated with fatty acids from oils, polishing compounds, handling, ete., acidic atmos- pheres high humidity. Electroplating finishes are applied beryllium copper exactly the same way they are copper, bronze and brass. For normal pro- tection and retention lighted-colored appearance, nickel plating usual, with nickel-chro- mium preferable for assuring com- plete resistance from attack over long periods. For electrical purposes, with special reference retaining exceedingly low contact resistance, gold silver employed com- IRON AGE, November 15, 1945 bination silver and rhodium, par- ticularly resistance wear addi- tionally necessary, may mov- ing contacts. For easy soldering tin plating used basis. These elec- troplate finishes necessitate particular attention the cleaning the sur- faces components, particularly after heat treatments, and then, providing the proper solutions have been em- ployed for these, difficulty should encountered with electroplating from the normal electrolytes. The removal oil and grease from the surfaces intermediate final stages production, well re- moval swarf chips presents difficulties, and the usual processes employed for other copper-rich metals such phosphor bronze, aluminum bronze, brass, cupro-nickel, etc., are applicable. These include solvent meth- ods, such as, trichlorethylene vapor degreasing, those requiring the in- expensive inflammable solvents such solvent naphtha, benzine, white spirit, and the like, these all being operated normal shop temperature. They also include processes using aqueous alkaline solutions such mixture equal parts soda ash and sodium metalsilicate. These clean- ers are used hot, the the boiling point, and preferably with the agitation provided com- pressed air fed perforated coil the base the cleaner tank. Two water washes remove the alkali from the parts completely must fol- low. The first these can advan- tageously cold water, and the sec- ond hot, from which drying off can easily achieved. these degreasing processes, the solvent methods will remove liquid oils, but will not remove soap base greases soap containing soluble oils. Liquid solvent must used chips and loose dirt are elim- inated because vapor cleaning meth- ods not touch extraneous matter this type. Again, using cold solvent processes, the precaution should taken employing two baths solvent series, one which clean the work, and the other for final rinse remove the dirty solvent from the first immersion. The condensation trichlorethylene vapor degreasing plant, course, takes care this point. The aqueous alkali cleaning com- pounds can designed remove any loose contamination, such mineral oils becoming emulsified, fatty oils saponified and soap base material emulsified and saponified. Loose dirt and swarf are pushed off the work virtue movement the work, agitation the liquid. However, heavy oily contamination has dealt with, then aqueous cleaners become very easily fouled, particular- much mineral oil lubrication concerned, and efficiency lost be- cause proper emulsification not achieved and oily layer separates top the cleaning solution. This tends contaminate the work passes through this layer upon its withdrawal from the vat, and the resulting film upon the surface the work not properly removed, all, the final water rinses. fact, contamination the latter usually occurs such circumstances, despite constant flow clean water the rinse tanks. The difficulty can off- set using the best balance caus- tic and mild alkalies suit the type contamination encountered, and have two alkali tanks, one which the bulk the contamination re- moved, removi necessé for plating have these most heat pering cipitat used ous sulphu agents potass the tures dippin ments soak tion, period oxidiz condit acid from tratec upon black low quire 68° perio the was sion, resul was stain acid from trate oxide givir solut acid from pera i} | | | | H i} hi 4 | if | 1] { | ' } | | | moved, and for the final cleaning. Regarding the acid solutions for removing oxide scale and tarnish, necessary for giving neat finish, and for preparing work prior electro- plating, number compositions have been suggested. number these have been tried determine the efficient, using beryllium copper heat treated ordinary fan tem- pering furnace 590° 610° for represent the average worst condition components after pre- cipitation hardening. The pickles used included sulphuric acid vari- ous concentrations water, dilute acid containing oxidizing agents such copper sulphate potassium sodium dichromate, and the usual sulphuric nitric acid mix- tures that are employed for the bright dipping copper, brass and phos- phor-bronze. Also, successive treat- ments were examined, using first soak straight sulphuric acid solu- tion, followed immersion period the solution containing the oxidizing agent. The various acid solutions investigated and operating conditions are given below: SOLUTION NO. 1—10 pct sulphuric acid solution. This was prepared from volume commercial concen- trated acid and volumes water. Employing this solution upon immersion the work, the black scale was quickly removed. lower temperature 120° 140° longer immersion time was re- quired, the maximum being min. ordinary shop temperatures 68° 77° considerably longer period was entailed, min being the maximum. each case, the black was completely removed immer- sion, that is, without mechanical aid rubbing brushing, but the resultant appearance, although clean, was dull and patchy, with coppery stains, SOLUTION NO. 2—25 pct sulphuric acid solution. This was prepared from volume commercial concen- trated sulphuric acid and volumes water. Using this pickle 190° 212° complete removal the oxide coating occurred immediately, giving finish appearance for solution No. Employed lower temperatures, similar results those recorded under No. were obtained. SOLUTION NO. 3—75 pct sulphuric acid solution. This was prepared from volumes commercial concen- trated sulphuric acid and volume water. With immersion tem- perature 190° 212° removal the black oxide was al- most immediate. The resulting appearance the work treated was similar that recorded un- der solution No. and treat- ments lower temperatures gave longer pickling times the same order those for solution No. SOLUTION NO. bright dipping mixtures. One the procedures commonly employed for copper and brass was adopted, giving immer- sion rich nitric acid mix- ture, then through water wash- ing, followed treatment sulphuric rich solution, and finally water washing. These two acid solutions were pre- pared for commercial concen- trated acids, the first from volumes nitric acid and vol- ume sulphuric acid, and the second from volumes sulphuric acid and volume nitric acid. They were employed ordinary temperatures 68° 72° Treatments this type were unsuccessful, being without effect upon the oxide scale. SOLUTION NO. 5—dilute sulphuric acid containing copper sulphate oxidizing agent. The solution was prepared from pct volume commercial concentrated sulphuric and pet weight crystalline copper sulphate. Employed cold, re- sults were not very satisfactory, the oxide scale not being much affected min. SOLUTION NO. dilute sulphuric acid containing potassium dichromate oxidizing aegnt. This was pre- pared from volume commercial concentrated sulphuric acid and 199 volumes water, plus pct weight potassium dichromate. The solution was used normal shop tem- peratures 68° 77° caused loosening the oxide scale from min, part which could then flushed off with water jet. Com- plete cleaning could not achieved even with successive treatments this solution. Moreover, when deal- ing with mass small irregular shaped articles, was found impossi- ble flush off loose scale without redepositing upon other articles the batch mere mechanical en- tanglement. SOLUTION NO. 7—more dilute sul- acid containing potassium di- chromate oxidizing agent. This solution was prepared from volume commercial concentrated sulphuric acid and volumes water, plus pet weight potassium dichro- mate. Employed cold, this solution SELECTOR disk for Fairbanks-Morse scale. Disk 0.045-in. gage beryllium copper with 525 teeth cut circle. was not effective No. but referred again later satisfactory combination treatments. SOLUTION NO. nitro-sulphuric acid containing chlorides. This solu- tion was prepared from volumes commercial acid, volume acid and vol- ume water, and the mixture pct weight hydrochloric acid was added. The solution was used 68° 77° The mixture was not suc- cessful removing black oxide from beryllium copper immersion periods min. Acid Pickle and Dichromate While the straight acid treatments (Nos. and above) proved satisfactory for giving clean surface, free from black oxide, the appearance produced was not suf- ficiently neat for final finish, nor sufficiently clean basis for elec- troplating. The following combina- tions were therefore studied. (1) Acid copper sulphate followed acid dichromate solution. The 10- min treatment solution No. was followed immersion periods min solution No. without any evidence improved results. (2) acid followed acid dichromate solution. (a) The specimens were given 15-min immer- sion solution No. ordinary temperatures, washed water, and then treated for min the dichro- mate solution No. The first solu- tion removed the black oxide leaving dull copper finish somewhat dirty appearance, while the second cleaned this uniform coppery color very good appearance. (b) shorter period about min the first solution, and min the second, the weaker dichromate solution No. THE IRON AGE, November n- n- its ct, lly ite pe to re- cleaned but did not yield neat and attractive finish. (c) Again reducing the time the first solution employing hot 190° 212° very quick dip sufficing because the black oxide removed dis- solving immediately, then following min immersion the dichromate solution No. No. gave satisfac- tory results, but not good with the extended dip the cold sulphuric acid. Again, extended immersion the dichromate solution No. for periods min did not give fur- ther improvement without the detri- ment etching the rolling marks and other blemishes the material. The treatments solution No. various temperatures, with cor- responding immersion times, were fol- lowed immersion for min the dichromate solution No. and satisfactory results, yielding uni- form finish, were obtained. The di- chromate solution No. was equally effective for the purpose. (e) The longer treatments solution No. various temperatures were ex- plored conjunction with min Satisfactory results were obtained. Shop Practice clean work from precipitation-hard- ening heat treatments immersion dilute sulphuric acid solution volume acid, volumes water) ordinary shop temperatures, for then rinsed water and given quick immersion dilute dichromate solution volume sulphuric acid, volumes water, pct weight potas- sium ordinary shop for period from few seconds min required. Thor- ough water washing and drying has follow. When quicker treatments are specifically required, the acid solu- tion can used hot. The solutions can maintained chemical control the results obtained work passed through. Positive control chemical analysis is, however, preferred. The sulphuric solution can maintained pct concentration addition daily weekly ac- cordance with the amount work passed through them. the same time, stage reached after few periodic additions when more economic scrap the solution. the dichromate solution, has remembered that the di- chromate that the expensive ingre- dient, and this the active agent providing the uniform clean. Dust and dirt decompose well metal. 62—THE IRON AGE, November 1945 ADJUSTABLE pitch propeller hub cones. therefore advocated that this solution should used minimum volume the smallest convenient con- tainer. far possible, fresh solu- tions should made just before they are required, and they should kept covered when not use. Additions can made required chemical analysis, but additions beyond the practical economic point should avoided. Work that has been annealed solution-treated more difficult deal with because has been subject- min more. Usually found that the oxide scale heavier and more adherent, and consequence the simple cold treatments just recom- mended not fully meet the case. The hot acid solutions then have employed, following course with the cold dichromate immersion. The attention that obviously has afforded this cleaning stresses the fact that heat treatments should controlled precisely order min- imise the degree oxidation. When neutral reducing atmosphere fur- naces are available for the heat treat- ment, they are distinct advantage from this point view. landing gear ring, one third actual size. The straight sulphuric acid solu- tions only remove the oxide coating and not adversely affect the dimen- sions the components. Hence, im- mersion time consequence from this angle. The dichromate so- lutions, the contrary, dissolve the metal, and therefore can upset close dimensional tolerances. For this rea- son, immersion times must mini- mised, and advantageous agi- tate the work, for example, shaking baskets the solution. Minimised time also means lowest consumption potassium dichromate, and there- fore, longest life. adverse ence dimensions should occur immersion min. these acid cleaning solutions, the loss thickness weight for beryllium copper similar order that for copper. The straight sul- phuric acid solution does not cause appreciable loss even the very long periods the tests. The same can said for hot solutions. the other hand, appreciable attack occurs the solution containing potassium dichromate. Nevertheless, ment this solution will not exceed min the thickness loss will only the order 0.00001 in., which not only negligible practice, but probably less than the loss thick- ness due the formation oxide the heat treatment process, loss which has incurred any case because this oxide must removed. Cleaning for Electroplating cleaning specifically for electro- plating processes, all work should have been degreased and subjected the double acid cleaning for removal heat-treatment oxidation. Work not passing through heat treatment need not given the acid cleanses, but generally more convenient subject all work the same opera- tions. certainly safeguards against any included oxide. The best acid treatments ensure adherent platings have been found the usual bright dips employed for copper, phosphor bronze and brass, g., the composition and treatment already detailed under solution No. has already been shown that these solutions are ineffective the presence heat-treatment scale, and the latter must moved, and the finish brought into uniform condition means the dichromate solution, before the bright dip treatment applied. Otherwise, irregular attack with much local pit- ting occurs. Following the prescribed procedure, however, good bright clean finish obtained. The time | imn the sol | orc cou rin cas but ing rin cas the an re m Is Ww immersion each the nitro-sul- acid solutions need only few seconds and the loss dimen- sions negligible. Precautions must taken making acid additions the solutions maintain acid strength, that the original ratio nitric acid not exceeded, viz., excess nitric acid must avoided this may cause excessive attack. Thorough water washing must follow avoid carrying these acids over the plating solutions. going into alkaline plat- ing electrolytes, can advantageous- rinsed dilute sodium cyanide solution (about pct strength ordinary temperatures), followed, course, water rinsing. This cyanide rinse may advantageous any case for removal light oxide stains, but there may objections pass- ing work from alkaline cyanide rinse into acid electrolyte. this cold dilute sulphuric acid rinse between the cyanide treatment and the plating operation. this way, any minute film chemicals retained Spectroscopic BSERVATIONS tropenas converter flame through di- rect vision spectroscope indicate that ship between the bands the flame spectrum and the composition the metal the bath, Jazwinski re- ports paper the British Iron Steel Institute. the beginning the blow very faint continuous spectrum visible. this moment the flame dull red mingled with dense brown fume, and sparks are ejected diverging stream with number clusters scintillating sparks. The continuous spectrum becomes gradually brighter and stronger until the flame appears more bright with less clusters sparks and brown fumes. Then ejects are thrown out and fine, weak, yellow band appears the spectrum. times the ejects continue for several minutes and be- come very violent. The yellow band then very clear and steady. After the ejects have ceased the flame becomes longer and brighter with