THE MECHANICAL PROPERTIES OF SOME SINTERED MARAGING STEELS

Abstract

Maraging steels based on 18 and 12% nickel, and containing cobalt, molybdenum, silicon, copper, chromium, titanium, and aluminium in various proportions, were prepared in sintered form under varied processing conditions. The mechanical properties of the steels have been examined with particular reference to the effects of: (1) composition; (2) degree of shrinkage; (3) atmosphere, time, and temperature of sintering; and (4) compacting pressure. The influence of the type of iron-powder base was also studied.

The results demonstrate the possibility of producing, in the sintered and maraged condition and with only slight shrinkage on sintering, tensile strengths of the order of 95–110 kgf mm^?2 (60–70 tonf in^?2). Two compositions appear promising for further development as high-strength materials, and another to provide enhanced ductility. In all cases impact properties are similar to those characteristic of conventional sintered steels.