碳在镍基单晶高温合金中作用研究的进展  

Advance in Research of Carbon Effect on Single Crystal Ni-Base Superalloy

作　　者：余竹焕[1,2] 刘林[1] 赵新宝[1] 张卫国[1] 张军[1] 傅恒志[1] 

机构地区：[1]西北工业大学凝固技术国家重点实验室,陕西西安710072 [2]西安科技大学材料科学与工程学院,陕西西安710054

出　　处：《铸造》2009年第9期918-924,共7页Foundry

摘　　要：综述了碳对镍基单晶高温合金显微组织、缺陷、合金元素偏析行为、相稳定性以及拉伸性能、蠕变性能、疲劳性能等力学行为的影响及机理。总结得出,随碳含量增加,合金初熔点逐渐降低,合金中共晶数量和尺寸减少,一次碳化物逐渐增多。除W和Ta外,碳含量变化对其它合金元素的凝固偏析没有明显影响。随含碳量增大,合金蠕变寿命显著降低,最小蠕变速率增大。微量碳的添加提高疲劳寿命,屈服应力随含碳量增加而降低。比较并分析了碳对合金组织结构和力学性能的各种影响机制,并指出今后的研究方向。The effect of carbon on the solidification microstructure, grain defects, alloying elements segregation, phase stability and tensile, creep, fatigue properties of single crystal superalloys as well as the mechanism were introduced. The results indicate that with increasing of carbon content, the incipient melting temperature of alloys decreased, the volume fraction and the size of γ/γ′ eutectic increased, at the same time the creep life greatly decreased and minimum creep rate increased. The solidification segregation also changed with increasing of carbon content, the segregation of W and AI decreased, but the segregation of Ta and Ti increased. Minor addition of carbon improved fatigue life, and the yield stress decreased with increasing of carbon level. The effecting mechanisms of carbon addition on the microstructure and mechanical properties were compared and analyzed, and the research direction in future is pointed out.

关 键 词：微量元素 碳 镍基高温合金 显微组织 

分 类 号：TG132.32[一般工业技术—材料科学与工程]