铪元素对单晶高温合金凝固特征的影响  

Effects of Hafnium on Solidification Characteristics of Single Crystal Superalloy

作　　者：史振学[1] 刘世忠[1] SHI Zhenxue;LIU Shizhong(Science and Technology on Advanced High Temperature Structural Materials Laboratory,Beijing Institute of Aeronautical Materials,Beijing 100095,China)

机构地区：[1]北京航空材料研究院先进高温结构材料重点实验室,北京100095

出　　处：《热处理》2020年第4期7-11,共5页Heat Treatment

摘　　要：为了确定铪元素在单晶高温合金中的作用,在真空定向凝固炉中制备了铪含量为0.10%和0.47%(质量分数)的单晶高温合金。借助于JMatPro软件、光学显微镜、差热分析、扫描电镜等研究了铪含量对合金凝固特征的影响。结果表明:较高的铪含量能提高MC碳化物的稳定性,抑制M23C6的形成,降低合金的固-液相线,增加糊状区宽度,并使γ’相的体积分数稍有增加,一次枝晶间距稍有减小,共晶含量增加,热处理后γ’相尺寸减小,立方化程度提高。Single crystal superalloys with 0.10%and 0.47%Hf by mass were fabricated in a directionally solidified vacuum furnace to identify the action of hafnium element in them.The effect of hafnium content on solidification characteristics of the alloy was investigated by the aid of JMatPro software,OM,DTA and SEM.The results showed that the higher hafnium content could(a)render MC carbide stabler,suppress the transformation of MC into M23C6;(b)lower the solidus-liquidus temperature,increase the wide of pasty state zone;(c)cause the volume fraction of γ' phase to increases slightly and the spacing of primary dendrite to decrease slightly;(d)increase the amount of eutectic phase;and(e)lessen the size of γ' phase and enhance its cubic degree after heat treatment.

关 键 词：单晶高温合金 铪含量 凝固 

分 类 号：TG142.1[一般工业技术—材料科学与工程]