定向凝固钴基高温合金DZ40M的热处理研究

研究了热处理对新研制的定向凝固钴基高温合金DZ40M组织和性能的影响。结果表明 :12 80℃ / 4h固溶处理可完全溶解DZ40M合金中初生碳化物M7C3 和MC ,合金成为单相固溶体。95 0℃和 10 5 0℃时效处理可使DZ40M合金发生硬化 ,以 95 0℃时效硬化效果更为明显 ,相应的峰时效制度为 95 0℃ / 12h和 10 5 0℃ / 2 4h。时效处理引起M2 3 C6沉淀析出。 95 0℃ / 12h时效显著提高DZ40M合金室温强度和高温持久寿命 ,同时也减少了合金塑性 ,但合金仍保持一定的塑性。 10 5 0℃ / 2 4h虽然能增加室温拉伸性能 ,但削弱了高温持久性能

Study on heat treatment of DZ40M directionally solidified cobalt base superalloy

DZ40M alloy is a newly developed directionally solidified cobalt-base superalloy. The present work investigated the effect of heat treatment on microstructures and mechanical properties of DZ40M alloy. The results showed that solution treatment at 1280℃ for 4h could dissolve the primary carbides M7C3 and MC essentially and the alloy became a single phase solid solution. Aging treatments at both 950℃ and 1050℃ could harden the alloy and 950℃ aging caused a more effective hardening. Two peak aging treatments were determined as 950℃/12h and 1050℃/24h. Aging treatments resulted in secondary M23C6 precipitation. 950℃/ 12h treatment increased room-temperature strength and stress-rupture life at high temperature substantially and reduced ductility. However, in spite of it, the alloy still has adequate ductility. Although it increased room-temperature mechanical properties, 1050℃/ 24h treatment deteriorated stress-rupture properties at high temperature.