热锻开坯对高铌TiAl合金微观组织的影响  

Effect of hot forging on microstructure of TiAl alloy containing high Nb

作　　者：苏喜孔[1] 李树索[1] 韩雅芳[1] 李臻熙[2] 徐向俊[3] 徐丽华[3] 林均品[3] 陈国良[3] 

机构地区：[1]北京航空航天大学材料科学与工程学院,北京100083 [2]北京航空材料研究院,北京100095 [3]北京科技大学新金属国家重点实验室,北京100083

出　　处：《中国有色金属学报》2004年第8期1410-1414,共5页The Chinese Journal of Nonferrous Metals

摘　　要：采用热等静压技术处理了高铌TiAl合金铸锭,对直径为115mm的高铌TiAl合金铸锭在1150～1300℃进行了热锻开坯。结果表明:热等静压处理后的高铌TiAl合金由大量粗大的α2/γ片层晶粒和少量的γ等轴晶、B2相等组成,晶粒度约为80～150μm;通过变形量为75%的2次锻造成形后锻饼表面和内部质量较为完好,没有出现裂纹和太多的氧化现象;铸态粗大片层组织在变形后基本破碎,晶粒得到明显细化。The ingot of as-cast TiAl alloy containing high Nb was dealed with HIP(hot isostatic pressing). The hot forging for large ingot with 115 mm in diameter of the TiAl based alloy containing high Nb was carried out in the temperature range of (1 150)1 300 ℃. The results show that TiAl alloy containing high Nb is composed of small amount of γ and B_2 phase and large of coarse α_2/γ lamellar structure with colony size of about 80150 μm after HIP. After twice forging with total deformation degree of 75%, the quality of the surface and inside of the pancake is good, and there is no cracks and evident oxidation. The as-cast lamellar structure is basically broken down and the grain gets fined obviously.

关 键 词：高铌TIAL合金 热锻开坯 微观组织 

分 类 号：TG146.2[一般工业技术—材料科学与工程]