Effect of carbon and boron additions on segregation behavior of directionally solidified nickel-base superalloys with rhenium  

碳和硼对高铼含量的定向凝固镍基高温合金元素偏析行为的影响(英文)

作　　者：胡勤[1,2] 刘林[1] 赵新宝[1] 高斯峰[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,西安710072 [2]中国兵器科学研究院宁波分院,宁波315103

出　　处：《Transactions of Nonferrous Metals Society of China》2013年第11期3257-3264,共8页中国有色金属学报（英文版）

基　　金：Projects(2011CB610406,2010CB631202)supported by the National Basic Research Program of China;Projects(51101120,50931004,51171151)supported by the National Natural Science Foundation of China

摘　　要：The phase transformation temperature, segregation behavior of elements and as-cast microstructure were investigated in experimental nickel-base superalloys with different levels of carbon and boron. The results show that the liquidus temperature decreases gradually but the carbide solvus temperature increases obviously with increasing carbon addition. Minor boron addition to the alloy decreases the liquidus temperature, carbide solvus temperature and solidus temperature slightly. Apart from rhenium, the segregation coefficients of the elements alter insignificantly with the addition of carbon. The segregation behavior of rhenium, tungsten and tantalum become more severe with boron addition. The volume fraction and size of primary carbides increase with increasing carbon addition. The main morphology of the carbides is script-like in the alloys with carbon addition while the carbide sheets tend to be concentrated and coarse in the boron-containing alloys研究元素碳和硼对含铼镍基定向柱晶高温合金相转变温度、元素偏析和碳化物析出相的影响。结果表明:随着碳含量的增加,液相线温度逐步降低,而碳化物的析出温度上升。硼的添加造成合金液相线温度、碳化物析出温度和固相线温度均下降。随着碳含量的增加,铼元素的偏析先增大后减小,而其它元素的偏析程度变化并不是很大。铼、钨、钽的偏析随硼的加入而逐渐增大。合金中碳化物的形态主要为汉字体状,碳化物数量随着碳含量的增加逐渐增大。添加硼元素的合金中析出的碳化物较不含硼元素的合金中析出的碳化物更加集中和粗大。

关 键 词：CARBON BORON segregation behavior directional solidification nickel-base superalloys 

分 类 号：TG132.32[一般工业技术—材料科学与工程]