Fansteel CHEMICALS A N D
MATERIALS
A l u m i n u m f o r Tanks a n d Vessels.
Basic technical guide to design, fabrica tion, and applications of aluminum tanks and vessels. More than 100 general types of chemicals for which aluminum applications are advantage ous. Dept. IEC, Reynolds Metals Co., 2500 South Third St., Louisville, Ky. 66 Anti-Corrosive Fastenings. Price, stock, and delivery information for large line of stainless steel and nylon fastenings. 138 pages. Dept. IEC, Anti-Corrosive Metal Products Co., Inc., Castleton-onHudson, Ν. Υ. 67 Butadiene. Technica' manual, claimed to be first printed for butadiene. This 42-page book contains complete physical properties, polymerization data, chem ical properties, and detailed information on all principle reactions. Dept. IEC, Petro-Tex Corp., P.O. Box 2584, Houston 1, Tex. 68 Carbon-14. Technical bulletin giving stock list of commonly used carbon-14labeled compounds. Bull. N-78, Dept. IEC, Nucleonic Corp. of America, 196 Degraw St., Brooklyn 37, Ν. Y. 69 Cellulose Acetate Butyrate. A 75page study of the chemistry and physical behavior of cellulose acetate butyrate in protective coatings. Comprehensive summary of the laboratory and com mercial experience gained by Eastman chemists in 27 years' work with the ester. Each type is discussed individually in terms of its general properties, useful solvents, plasticizers, and other modifying materials. Typical uses are also given as a guide in the selection of the best ester for a given application. Dept. IEC, Eastman Chemical Products, Inc., Chemical Division, Kingsport, Tenn. 70 Chlorothene. Properties and uses of versatile cold-cleaning solvent, inhibited 1,1,1-trichloroethane. Safety, advan tages pointed out. Dept. IEC, Solvents Sales Dept., Dow Chemical Co., Midland, Mich. 71 Concentration
Conversion
Chart.
For petroleum chemists, chart provides an easy and rapid means of converting petroleum additive concentrations into the seven units most frequently used in the lab. Dept. IEC, Eastman Chemicals Products, Inc., Kingsport, Tenn. 71 To receive any of the literature listed here, simply send a request on your company letterhead to the manufac turer whose address you find at the end o f each item
Corrosionomics REGISTERED
U.S.
PATENT
OFFICE
A JOURNAL OF USEFUL INFORMATION FOR THE SOLUTION OF CORROSION PROBLEMS
TANTALUM INERT TO ACID PLATING BATHS The inertness of tantalum to a broad spectrum of acids and oxidizing agents has resulted in increasing usage of this metal for heating and cooling equip ment in acid electroplating systems. Plating baths are heated, usually with steam, at start-up and subse quently must be cooled in most cases during continuous operation. The heat generated by the electric power not consumed in the actual deposition of metal usually is greater than the heat lost by radiation, evaporation, etc., and that used to heat the parts being plated. Coils placed in the plating tank and external heat exchangers thru which the process solution is pumped are the chief types of heating and cooling equipment used. Corrosion is a major factor in the choice of mate rials for such units. U-coils and tube and shell heat ex changers made of tantalum are widely applied in the strongly oxidizing chro mium plating baths, composed of 33 to 53 ounces per gallon of chromic acid, CrOe, in dilute H2SO4 at a C r 0 3 / H 2 S 0 4 ratio of 100/1. They are used with both steam and water to regulate the temperature at the de sired value in the range 110°-150°F. The temperature of the acidic nickel plating baths, containing nickel sul fate and/or nickel chloride at pH's of 0.9-4.8, is controlled similarly with tantalum heating and cooling units. Acid zinc bath temperature regulation
Installation of " U " type t a n t a l u m heaters w i t h insulating hoses of n o n - c o n d u c t i n g materials in p i p i n g . Courtesy Metol & Thermit
Corporation
likewise can be handled with tantalum equipment. In zinc baths using insol uble anodes the presence of free oxy gen discharged at the anode has no effect on tantalum. Most electropolishing is done in solu tions containing a variety of acids, in cluding perchloric, acetic, phosphoric, chromic and mixtures of these and others. With the exception of those containing HF or free SO3, tantalum is inert to all such solutions over the temperature range used, 110° to 250°F. In addition to its inertness to acidic solutions, tantalum has several other advantages. Thin wall tubing can be used in the heating and cooling units since no extra thickness need be pro vided for corrosion loss, no heat-insu lating corrosion scale forms on tanta lum, no contamination of the plating bath by tantalum is encountered, and space requirements are minimum.
Free Tantalum Test Kit A corrosion test kit, available without charge to research technicians, con tains both tantalum sheet and wire. Request it on your letterhead. The above condensation is typical of articles which appear in CORROSIONOMICS, a Fansteel publication. Mail us your name for in clusion on our mailing list, j
Typical Acidic Plating Baths TYPE
REAGENTS*
Chromium
Cr03, H2S04
pH
< 1
nickel
NiCI2, NiS0„, HB03
1-4
Zinc
HA.ZnSlU
1-4
Copper
H2S04, CuS04
< 1
TEMP.
110°-150°F. 90°-!60°F. 80°F. 70°-120°F.
* Tantalum inert to these reagents
