COLD-WORKING AND HEAT-CRACKING IN Ni-Cu-BASE MONEL ALLOY K-500
(1.Department of Materials Science and Engineering, Northeastern University, Shenyang110006, P. R. China;
2.Institute of Metal Research, Chinese Academy of Sciences, Shenyang110015, P. R. China)
2.Institute of Metal Research, Chinese Academy of Sciences, Shenyang110015, P. R. China)
Abstract: Cold-working and its effect on heat cracking of Monel alloy K-500 were investigated. The results showed that cold-working hardening is limited for its strong effect on heat cracking, although Monel alloy K-500 has good cold workability. It was revealed that the main reasons of heat cracking, which initiates on the surface of the specimens and propagates intergranularly into the inner during aging, are the residual stress due to cold working, the heat stress due to aging and the surface brittleness occuring in early aging stage. It was proved that mechanical straightening is a beneficial and economical method to prevent Monel alloy K-500 from heat cracking.
Key words: Monel alloy K-500 cold-working heat cracking mechanical straightening