工程化高Nb钛铝合金锻造性研究  

Investigation of the workability of pilot ingot of high Nb containing TiAl based alloy

作　　者：徐向俊[1] 林均品[2] 王艳丽[2] 宋西平[2] 林志[2] 陈国良[2] 

机构地区：[1]中原工学院材料与化工学院,郑州450007 [2]北京科技大学新金属材料国家重点实验室,北京100083

出　　处：《材料科学与工艺》2007年第5期709-712,共4页Materials Science and Technology

基　　金：国家自然科学基金资助项目(50274005).

摘　　要：通过热模拟实验对高Nb-TiAl的锻造工艺参数进行探索,并根据该参数对工程化规模的铸锭进行了成功的锻造.同时通过金相显微镜和扫描电镜对材料锻造前、后的组织变化进行了分析.结果表明高Nb-TiAl合金有较好的锻造性能,变形抗力随变形温度的升高和应变速率的降低而降低.在α+γ两相区对高径比为1.10～2.13的铸锭进行包套锻造,可以得到形状规则、无裂纹的饼材.锻造后饼材的大部分组织为几乎完全消除了原来片层团的细小的双态组织,而近表面区为残余铸造片层和再结晶晶粒的混合组织.Thermomechanical processing parameters for high Nb containing TiA1 based alloy were investigated by thermal simulation tests. According to the results can forging processes of pilot ingots were conducted, and the microstructures of the ingots before and after hot working were analyzed by optical microscopy and scanning electron microscopy （SEM）. The results showed that the high Nb containing TiAI alloy had good deformability and the deformation resistance decreased with the increase of temperature and the decrease of strain rate. Good appearance, crack - free pancakes can be obtained by can forging at the temperature of α ＋ γphase regiion for the ingots with a height - to - diameter （H/D） ratio of 1.10 - 2. 13. The as - forged microstructures consisted of the refined duplex microstructure for the major part of the pancakes with retained lamellar colonies and par- tially recrystallized grains for the near surface zone of the pancak

关 键 词：高Nb-TiAl合金 热模拟试验 锻造性能 包套锻造 双态组织 

分 类 号：TG146.2[一般工业技术—材料科学与工程]