Joseph of the inspect
R. Mares, vice president of Monsanto Chemical Co. ami general manager Texas division; and H. K. Eckert, manager of the Texas City plant, tnemarial dedicated to the 145 employees lost in the disaster
Concluding the day was a banquet address by K a r l T . Compton. D r . Compton examined the role of science in its relationship to the major aspirations and objectives of our people, stressed the increasing efforts of industry to use our natural resources more efficiently and the closer relationships between industrial and university labora.tories. "Men a n d ideas," he said, "have constructed our past and will forge our future." Our basic problems will b e solved by "the understanding, skill and loyalty of great numbers of people who are first the pioneers ^md second t i e craftsmen and third t h e beneficiaries of these ideas." The words of Mr. Rand expressed the spirit of Monsanto and the d a y : "We had lost many of the men who had built the [fonner] plant—we had lost some of the men in whose dreams a better plant had formed. Their friends and associates, who still lived, shared their dreams. Could a. company abandon such a force?.. .andso *westayed in Texas City.·*'
Magnetic Cliitch Holds MPA Interest A STAFF REPORT J. H E magnetic fluid clutch, discussed by H. D . Saunderson, National Bureau of Standards, was a subject of much interest to the meeting of the Metal Powder Association in Chicago April 5 and 6. A record turn-out of nearly 300 evinced the interest in the comparatively new industrial process, powder metallurgy. In discussing the characteristics of materials involved in the clutch, Mr. Saunderson emphasized the requirements for operation of the unit which consists essentially of two plates, the space between which is filled with a magnetic liquid, the characteristics of which are controlled by A magnetic flux. The liquid, he said, contains the powder of some magnetic material, an oil or other vehicle, and an additive to improve the physical characteristics of the mixture. Iron carbonyl powder has been the most universally successful magnetic material, stated Mr. Saunderson, while molybdenum powders have all of the desirable attributes except high permeability. For this reason their use has been discontinued generally. Hydrogen-reduced iron is not satisfactory because of corrosion and catalytic activity toward most of the oils used. The fluids which show the most promise of being useful in the highest temperature ranges, according to Mr. Saunderson, are the trifluorochloroethylenes, which, however, give off toxic vapors at 450° F. Hexachlorobutadiene is interesting by virtue of its nonflammability, but it does tend .to decompose a t high temperatures and form gels. Polymethylsiloxanes are useful below 250 ° F. Agents are needed to prevent settling of the powder. Oleic acid or alkylaryl polyglycol ether may be used
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to give thixotropic mixtures at low temperatures, polyethylene glycol oleate up to 175° F., and butyl oleate up the 300° F. Wetting agents to assure wetting of the surfaces of individual particles are also useful. Those recommended were paradichlorobenzene, sulfotricarbolyllate, and dioctyl sodium sulfosuccinate, but, it was stated, none has been found successful above 200 ° F . Other uses for the principle involved in this clutch were suggested, including magnetic valves, molding materials, dash pots, and shock absorbers.·
J. L. Bonanno, Lionel Corp., discussed powder metallurgy from the design engineers standpoint, noting that while "powder metallurgy is not a panacea for all design engineers' troubles, it is peculiarly well-suited for t h e fabrication of many small structural parts produced in large quantities.'' Mr. Bonanno described how the Lionel Corp. has made an almost complete change-over from die casting, machining, and slain ping production methods to powder metallurgy methods wherever possible in the manufacture of their model electric trains.
D. .Vf. Borcina of Metal Powder Association, Methods magazine, and G. L. Bachner, Powdered
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IV. P. Winsor, of Materials and Metal Prod acts Corp. of America
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