合金元素对一种定向凝固钴基高温合金组织和性能的影响

EFFECT OF MINOR ELEMENTS ON MICROSTRUCTURE AND PROPERTIES IN A COBALT-BASE SUPERALLOY

本文研究微量合金元素Ｃ，８，Ａｌ，Ｚｒ对钴基高温合金组织和性能的作用．表明Ｃ．Ｂ含量增加，极为显著地提高合金高温持久性能，Ａｌ的影响次之．随Ａｌ含量增加．合金性能降低，Ｚｒ无明显影响，Ｃ和８有较为明显的交互作用．据此，研制成Ｘ４０Ｍ合金，该合上和Ｘ４０相比，高温持久性能和塑性都有极为显著的提高，可提高使用温度４５℃．合金有两种碳化物强比机制：碳化物承载和碳化物弥散强化，合金元素是通过改变合会相变温度和碳化物相的含量，种类。

Experimental studies on effects of minor elements in a cobalt-base superalloy have been carried out to develop newer high-strengh one.It is found that the high temperature stress-rupture properties increase very rapidly with C or B and the mutual effect is shown obviously between them.But Al weatens the properties and Zr has no obvious effects.Compared with X40 alloy,the stress-rupture life of the new alloy can prolong 6 to 8times and the availabe temperature can raise 45℃.Two carbide strengthening machanisms seem to be carbide beazing capacity and precipitate strenghening.The variations of alloy properties result in the changing of the carbide transformation temperature as well as content.type,distribution and morphology of carbide induced by miner dements