徐向俊3，徐麗華3， 林均品3， 陳國良3
( 1. 北京航空航天大學(xué) 材料科學(xué)與工程學(xué)院, 北京 100083; 2. 北京航空材料研究院, 北京 100095;
3. 北京科技大學(xué) 新金屬國家重點(diǎn)實(shí)驗(yàn)室, 北京 100083)
摘 要: 采用熱等靜壓技術(shù)處理了高鈮TiAl合金鑄錠， 對直徑為115mm的高鈮TiAl合金鑄錠在1150~1300℃進(jìn)行了熱鍛開坯。 結(jié)果表明：熱等靜壓處理后的高鈮TiAl合金由大量粗大的α2γ片層晶粒和少量的γ等軸晶、 B2相等組成，晶粒度約為80~150μm； 通過變形量為75%的2次鍛造成形后鍛餅表面和內(nèi)部質(zhì)量較為完好， 沒有出現(xiàn)裂紋和太多的氧化現(xiàn)象；鑄態(tài)粗大片層組織在變形后基本破碎， 晶粒得到明顯細(xì)化。
關(guān)鍵字: 高鈮TiAl合金；熱鍛開坯； 微觀組織
TiAl alloy containing high Nb
XU Xiang-jun3, XU Li-hua3,
LIN Jun-pin3, CHEN Guo-liang
（ 1. Research Institute of Advanced Materials,
Beijing University of Aeronautics & Astronautics, Beijing 100083, China;
2. Beijing Institute of Aeronautical Materials, Beijing 100095, China;
3. State Key Laboratory for Advanced Metals and Materials,
University of Science and Technology Beijing, Beijing 100083, China）
Abstract: The ingot of as-cast TiAl alloy containing high Nb was dealed with HIP(hot isostatic pressing). The hot forging for large ingot with 115mm in diameter of the TiAl based alloy containing high Nb was carried out in the temperature range of 1150℃-1300℃. The results show that TiAl alloy containing high Nb is composed of small amount of γ and B2 phase and large of coarse α2γ lamellar structure with colony size of about 80-150μm 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.
Key words: TiAl alloy containing high Nb; hot forging; microstructure
