(中南大學(xué) 材料科學(xué)與工程學(xué)院，長沙 410083)
摘 要: 研究固溶溫度和時效溫度對Ti62421s高溫鈦合金顯微組織、相成分和常溫拉伸性能的影響。結(jié)果表明：在兩相區(qū)進行固溶處理時，隨著固溶溫度的升高，合金組織中的α相減少，β轉(zhuǎn)變組織(βt)增多，當固溶溫度進入β相區(qū)后為籃網(wǎng)狀β轉(zhuǎn)變組織；隨著時效溫度的升高，α相長大；隨著固溶溫度和時效溫度的升高，β轉(zhuǎn)變組織中只有Al含量升高，其他合金元素的含量都下降；隨著固溶溫度的升高，強度和斷面收縮率先升高后迅速降低，伸長率逐漸下降；經(jīng)(980 ℃，1 h，AC)+(550 ℃，8 h，AC)熱處理后，合金可以獲得較好的綜合性能，抗拉強度達1 077.04 MPa，伸長率達13.6%，斷面收縮率為26.02%。
關(guān)鍵字: 鈦合金；Ti62421s；熱處理；顯微組織；力學(xué)性能
mechanical properties of Ti62421s high temperature titanium alloy
（School of Materials Science and Engineering, Central South University, Changsha 410083, China）
Abstract:The effect of solution temperature and aging temperature on the microstructure and mechanical properties of Ti62421s high temperature titanium alloy were studied. The results show that, the content of primary α-phase decreases and the content of transformed β phase increases with increasing solution temperature when the alloy is treated in α+β field, only weave transformed β-phase exists when the alloy is treated in β field. With the aging temperature increasing, primary α-phase size grows up. With increasing solution temperature and aging temperature, only the content of aluminum increases in the transformed β-phase, where as the contents of other alloying elements decrease. With the solution temperature rising, and the strength and area reduction rate increase firstly and then decrease rapidly, the elongation decreases. The heat treatment of (980 ℃, 1 h, AC)+(550 ℃, 8 h, AC) for this alloy is preferable for optimum mechanical properties, and the tensile strength, elongation and area reduction rate of the alloy are 1 077.04 MPa, 13.6%, 26.02%, respectively.
Key words: titanium alloy; Ti62421s; heat treatment; microstructure; mechanical properties
