(中南大学 材料科学与工程学院，长沙 410083)
摘 要: 研究固溶温度和时效温度对Ti62421s高温钛合金显微组织、相成分和常温拉伸性能的影响。结果表明：在两相区进行固溶处理时，随着固溶温度的升高，合金组织中的α相减少，β转变组织(βt)增多，当固溶温度进入β相区后为篮网状β转变组织；随着时效温度的升高，α相长大；随着固溶温度和时效温度的升高，β转变组织中只有Al含量升高，其他合金元素的含量都下降；随着固溶温度的升高，强度和断面收缩率先升高后迅速降低，伸长率逐渐下降；经(980 ℃，1 h，AC)+(550 ℃，8 h，AC)热处理后，合金可以获得较好的综合性能，抗拉强度达1 077.04 MPa，伸长率达13.6%，断面收缩率为26.02%。
关键字: 钛合金；Ti62421s；热处理；显微组织；力学性能
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
