Modelling and kryptonate method of studying wear of plastic-working machines

The wear of tools of different quality used for forming plastics with and without filler was investigated. The method applied was the radiotracer technique using 85Kr. As krypton losses from the surface occur not only owing to wear but also as a result of changes in temperature and of corrosion it was necessary to eliminate the said factors. Thermal effects were removed after kryptonation by heat treatment of the surface at a temperature of 250 degC for a period of 1 hour. Corrosion effects were assessed by laboratory tests. The degree of wear of tools was determined at temperatures of 205, 220 and 235 degC and pressures of 8, 16 and 20 MPa. (Z.S.). 8 figs., 1 tab., 3 refs