Document qaw4XDaVxDGbazg1ZYpYbxJmE

iif!%?r)d<.\*'; ,,* SSpd^jtgtofi&ovi/umu, / Intra-Company Communication May 2, 1962 TO; Hr. J. R. Elvell cc: Messrs. J. V. Barnes S. Gratch R. J. Rumpf R. L. Van Alsten SUBJECT; Proposal for Cooperative Investigation of Cermet Brake Linings 'As a result of the investigation on cermet type materials for brake lining application, promising compositions have been developed in the iron-graphitesulphur system. In order to.accelerate thiB development ve have outlined our thoughts concerning vork to be done. Scientific laboratory The major variables to be studied in the lron-graphlte-sulphur system are composition and microstructure. Earlier results have shown that the coefficient of friction over a range of temperatures depends upon composition. For example, higher graphite promotes a lov coefficient of friction at low temperatures and a high one at elevated temperatures. The effect of increasing sulphur is to increase friction at low temperatures and decrease it at elevated temperatures. The importance of microatructure is emphasized by the drastic difference in friction behavior of liquid phase sintered and solid 6tate 6lntered materials. Significant variations in friction have been observed for fixed compositions by varying only the initial particle size of the iron. In conjunction with further studies on the effect of composition and microstructure on the friction behavior, the influence of sintering temperature and time must be considered. Data on the mechanical and physical properties of all specimens submitted for friction tests should be obtained. In addition, the Instrumentation Section should be requested to develop, Where necessary, additional testing equipment for expediting the evaluation of basic properties of the mater ials under 6tudy. Product Study Engineering Office It appears that, at least initially, procedure C on the T. P. Chase machine should be used as the main method of evaluation. However, it would seem desirable to make certain modifications. For instance, drums of a composition similar to that in current automobile production should be used. A record should be kept of the microinch finish of the drum, and possibly a brief study of the effect of this finish should be made (it is reported that General Motors uses a 177 * eooa isoi ; 1 PRODUCED BY FORD SCF-FORD-0358 2' finer finish of the drums to he used vith metallic linings than of those for organic linings). Certain competitive materials (e.g., General Motors' metal lic linings, best available organic linings) should be evaluated on the T. P. Chase machines and the results should be correlated vith actual vehicle per formance data. Of course our own metallic linings should be tested on vehicles vhenever the Product Study Engineeiing Office is satisfied that the laboratory results varrant 6ucb a study. We vould appreciate any comments, suggestions and criticisms of this proposal. Applied Science Department Scientific Laboratory M. Bumenik, Jr., Supervisor Non-Metallic Materials Section Applied Science Department Scientific Laboratory EEM:bf 8002 1862 $ PRODUCED BY FORD