Microstructure evolution of K6509 cobalt-base superalloy for over-temperature

摘要：

　　In this study,the K6509 cobalt-base superalloy were heat treated at different temperatures and the microstructure was detected by scanning electrical microscopy and electrical probe micro-analyzer.In as-cast K6509,the MC carbides are present as a discrete,blocky dispersion with a well-distributed Chinese script morphology and the eutectics(γ+ M23C6)and(γ+M7C3)can be seen.With the temperature increasing,the MC arise degeneration.Below 1150℃,the script-like MC is dominant; reaching 1200℃,the particle and block of MC are dominant; reaching 1250℃,few script-like MC is present.In as-cast alloy,the M23C6 and M7C3 carbides are lamellar eutectic with matrix.When temperature is up to 1150℃,the eutectic(γ+M23C6)disappears; however,much eutectic(γ+M7C3)can be found.When the temperature reaches 1200℃,a large amount of eutectic M7C3 is dissolved,and some pores form in the matrix,and some zones rich in Cr form around the pores.When the temperature is above 1250℃,many pores form in the matrix,the cause of pores is need to be studied further.The types and morphology of microstructures are different when the alloy is treated in different temperature.When the vanes are over heated or burnt,the temperature can be defined by examining the microstructure.It is useful for the researchers to check the over-temperature and analysis the failure mode and cause of vanes quickly.

关键词： K6509 Cobalt-base superalloy over-temperature M23C6 M7C3 MC

作者: WEI Zhen-wei ZHAO Wen-xia ZHOU Jing-yi LIU Chang-kui ZHENG Zhen QU Shi-yu TAO Chun-hu

作者单位: AVIC Beijing Institute of Aeronautical Materials,Beijing 100095,China;AVIC Failure Analysis Center,Beijing 100095,China;Beijing Key Laboratory of Aeronautical Materials Testing and Evaluation,Beijing 100095,China

会议类型: 国际会议

会议名称: 2014 Asia-Pacific International Symposium on Aerospace Technology(2014亚太航空航天技术学术会议)

会议地点: 上海

会议语种:英文

页码: 1-8

在线出版日期: 2014-09-24（万方平台首次上网日期，不代表论文的发表时间）