B元素对DZ424定向凝固合金凝固特性及性能的影响  

Effect of boron element addition on solidification characteristics and properties of directionally solidified superalloy DZ424

作　　者：吴保平[1,2] 吴剑涛[1] 李俊涛[1] WU Bao-ping1,2, WU Jian-tao1, LI Jun-tao1(1. High Temperature Materials Research Institute, Central Iron and Steel Research Institute, Beijing 100081 , China; 2. Beijing Key Laboratory of Advanced High Temperature Materials, Central Iron and Steel Research Institute, Beijing 100081, China)

机构地区：[1]钢铁研究总院高温材料研究所,北京100081 [2]钢铁研究总院高温合金新材料北京市重点实验室,北京100081

出　　处：《材料热处理学报》2018年第9期36-43,共8页Transactions of Materials and Heat Treatment

基　　金：北京市科技计划项目(Z131100006413005)

摘　　要：研究了B元素的加入对DZ424定向凝固合金凝固特性和性能的影响规律。结果表明：B元素的加入能显著降低合金的固/液相温度,加宽凝固范围,增加共晶含量;同时,由于B元素在碳化物中富集,使得碳化物形貌由草书状向块状转变。随着B含量的增加,粒状M3B2逐渐在共晶前沿析出;进一步增加B含量,硼化物形貌由粒状向条状转变。B的添加能够显著提高合金的持久性能,但当B添加量大于0.015%时,合金的持久性能显著降低。The effect of boron element addition on solidification characteristics and properties of directionally solidified superalloy DZ424 was studied. The results indicate that the addition of B element can sighificantly decrease the temperature solidus/liquidus phase,widen the solidification range,and increase the eutectic fraction. At the same time,due to the enrichment of B element in the carbides,the morphology of the carbides changes from script to block. With the increase of boron content,granular M3 B2 boride precipitates gradually around γ/γ＇ eutectics,and the morphology of the boride changes from granular to stripe with the further increasing of B content. The addition of B can significantly improve the rupture life of the directionally solidified superalloy,but when the content of B is greater than0. 015%,the rupture life of the alloys decreases significantly.

关 键 词：硼元素 定向凝固 凝固特性 性能 高温合金 

分 类 号：TG132.3[一般工业技术—材料科学与工程]