FRICTIONAL BEHAVIOR OF AL359 SIC/20P COMPOSITE UNDER ISOTHERMAL AND NONISOTHERMAL HOT-WORKING CONDITIONS AS A FUNCTION OF SURFACE-ROUGHNESS/

The frictional behaviour of 359/SiC/20p composite, using a graphite-ba sed lubricant, has been studied by means of ring-compression tests per formed under both isothermal and non-isothermal conditions. It was obs erved that the decrease of the inner diameter increases with increasin g surface roughness of the ring samples. Furthermore, with greater sur face roughness, the decrease in the inner diameter is affected by both temperature and strain rate, whilst a lower roughness value makes the interfacial friction almost insensitive to the working conditions. A comparison between the experimental data and calibration curves has en abled the determination of the shear friction factor as a function of surface roughness, temperature and strain rate. (C) 1997 Elsevier Scie nce S.A.