發(fā)布時(shí)間：2018-10-11 11:28

【摘要】：研究了不同熱處理工藝對(duì)高Nb-TiAl合金板材的顯微組織及力學(xué)性能的影響。采用鑄錠原料直接包套熱軋制備的板材主要由殘余粗化的片層團(tuán)、再結(jié)晶γ晶粒和沿軋制方向帶狀分布的β相組成。通過不同的熱處理工藝可以消除殘余片層和β相,分別獲得典型的雙態(tài)組織、近片層組織和全片層組織。對(duì)熱處理后具有雙態(tài)組織的板材進(jìn)行了室溫和高溫力學(xué)性能測試,結(jié)果表明:經(jīng)熱處理后,熱軋板材的室溫延伸率達(dá)到0.5%,屈服強(qiáng)度和抗拉強(qiáng)度分別提高到646MPa和691MPa,與鑄態(tài)相比,其室溫強(qiáng)度和塑性得到了改善,在850-900℃之間材料發(fā)生韌脆轉(zhuǎn)變,并且相應(yīng)斷裂機(jī)理從脆性的穿晶斷裂轉(zhuǎn)變?yōu)榭锥吹男魏撕途奂?br/>[Abstract]:The effects of different heat treatment processes on the microstructure and mechanical properties of high Nb-TiAl alloy sheet were studied. The plate prepared by direct coating hot rolling with ingot raw material mainly consists of residual coarsening lamellae, recrystallized 緯 grain and 尾 phase distributed along the rolling direction. The residual lamellae and 尾 phase can be eliminated by different heat treatment processes, and typical double, near lamellar and whole lamellar structures can be obtained, respectively. The mechanical properties of the sheet with double state structure after heat treatment were tested at room and high temperature. The results showed that the elongation at room temperature reached 0.5, the yield strength and tensile strength increased to 646MPa and 691MPa respectively after heat treatment, compared with the as-cast, the tensile strength of hot-rolled sheet was 691 MPA. The strength and plasticity at room temperature have been improved, the ductile and brittle transition occurred between 850 鈩，

本文編號(hào)：2264024