顯微組織的影響①
(中南大學(xué)粉末冶金國(guó)家重點(diǎn)實(shí)驗(yàn)室,長(zhǎng)沙410083)
摘 要: 用電子探針對(duì)Ti-45Al-7Nb-0·15B-0·4W的鑄態(tài)和經(jīng)過(guò)熱處理之后的顯微組織進(jìn)行了觀察和分析,并分析了熱處理工藝對(duì)Ti-45Al-7Nb-0·15B-0·4W顯微組織的影響。結(jié)果發(fā)現(xiàn): Ti-45Al-7Nb-0·15B-0·4W的鑄態(tài)組織經(jīng)過(guò)熱等靜壓和均勻化處理后,其晶團(tuán)尺寸減小,層片組織更為完整; Ti-45Al-7Nb-0·15B-0·4W合金的α相轉(zhuǎn)變溫度為(1 290±5)℃; Ti-45Al-7Nb-0·15B-0·4W合金在超過(guò)1 295℃的溫度進(jìn)行熱處理時(shí),其顯微組織由近層片
組織轉(zhuǎn)變?yōu)槿珜悠M織。經(jīng)過(guò)熱等靜壓和均勻化處理后Ti-45Al-7Nb-0·15B-0·4W合金的基本形貌為初生γ相+層片狀晶團(tuán),有β相析出,其形貌為針狀、點(diǎn)狀、顆粒狀。
關(guān)鍵字: 熱處理; TiAl;顯微組織
Ti-45Al-7Nb-0·15B-0·4W
LIU Bin, REN Bing, HUANG Bai-yun
（ State Key Laboratory of Powder Metallurgy,
Central South University, Changsha 410083, China）
Abstract:The microstructures of as-cast and as-heat treated Ti-45Al-7Nb-0·15B-0·4W were observed by electronprobe. The effect of heat treatment process on the microstructure of as-cast and as-heat treated Ti-45Al-7Nb-0·15B-0·4W was discussed. The results show that the microstructure of as-cast Ti-45Al-7Nb-0·15B-0·4W becomes fineafter being HIPped and heat treated, and a more perfect lamellar microstructure is got. The temperature ofαphase
transformation is between 1280℃and 1295℃. The microstructure of Ti-45Al-7Nb-0·15B-0·4W changes fromnear lamella(NL) to full lamella(FL) afterαphase transformation. After the alloy being HIPped and annealed, themicrostructure of Ti-45Al-7Nb-0·15B-0·4W alloy is primaryγphase and lamella, and the needle-like and granularβphase precipitates.
Key words: heat treatment; TiAl; microstructure
