(1. 寧夏東方鉭業(yè)股份有限公司 鈦材分公司，石嘴山 753000； 2. 西北工業(yè)大學(xué) 材料學(xué)院，西安 710072)
摘 要: 對(duì)Ti-6Al-6V-2Sn鈦合金棒材進(jìn)行鍛造、固溶及時(shí)效處理，利用光學(xué)顯微鏡、XRD、SEM 及力學(xué)性能試驗(yàn)對(duì)該合金不同固溶、時(shí)效工藝下的顯微組織和力學(xué)性能進(jìn)行研究。結(jié)果表明：Ti-6Al-6V-2Sn鈦合金鍛棒的組織為初生等軸α+β轉(zhuǎn)變組織，合金經(jīng)固溶處理后的組織為初生αp相、馬氏體α′、α″相和亞穩(wěn)β相，強(qiáng)度有所降低，斷面收縮率有所上升，說(shuō)明固溶處理有一定的軟化作用，但隨著固溶溫度升高，強(qiáng)度增加，塑性下降；經(jīng)固溶處理后的棒材在時(shí)效處理過(guò)程中，亞穩(wěn)態(tài)組織析出細(xì)小彌散的次生αs相，使合金強(qiáng)度明顯強(qiáng)化，塑性略有降低，且隨著時(shí)效溫度的升高，強(qiáng)化效果下降，塑性隨之提高。經(jīng)過(guò)綜合比較，并考慮強(qiáng)塑性的最佳匹配，可以確定本實(shí)驗(yàn)中Ti-6Al-6V-2Sn合金固溶時(shí)效熱處理的優(yōu)化工藝為(880 ℃, 1 h, WQ)+(580 ℃, 4 h, AC)。
關(guān)鍵字: Ti-6Al-6V-2Sn；固溶處理；時(shí)效處理；顯微組織；力學(xué)性能
（1. Titanium Product Plant, Ningxia Orient Tantalum Industry Co., Ltd., Shizuishan 753000, China; 2. School of Materials Science and Engineering, Northwestern Polytechnical University, Xi’an 710072, China）
Abstract:The influences of solution and aging treatment process on microstructure and properties of Ti-6Al-6V-2Sn alloy rods were investigated by using optical microscope (OM), XRD, scanning electron microscopy (SEM) and mechanical properties test. The results show that the as-forged microstructures of Ti-6Al-6V-2Sn alloy rods are fine isothermal primary α and transition β phases. After solution treatment, the microstructure is mainly composed of isothermal primary αp, martensite α′, α″ and metastable β phases. The strength decreases, but the reduction of area increases, which indicates that the solution treatment has a softening effect. With the rise of solution temperature, the strength increases subsequently, and the plasticity decreases. And fine dispersion secondary αs phase precipitates from the metastable structures after aging treatment process, the alloy can be strengthened significantly with slightly reduced plasticity. And with the aging temperature increases, the strengthening effect is reduced, and the plasticity increases. Through comprehensive comparison, considering the best match of the strength and plasticity, it can determined that the optimization solution and aging treatment process of Ti-6Al-6V-2Sn alloy in this experiment is (880 ℃, 1 h, WQ)+ (580 ℃, 4 h, AC).
Key words: Ti-6Al-6V-2Sn; solution treatment; aging treatment; microstructure; mechanical property
