(中南大學(xué) 粉末冶金國家重點(diǎn)實(shí)驗(yàn)室，長沙 410083)
摘 要: 采用冷等靜壓、高溫?zé)Y(jié)和直接高溫旋鍛的方法制備Mo-Ti-Zr合金棒材，研究不同退火溫度對合金力學(xué)性能與顯微組織的影響以及對斷面收縮率為30%的旋鍛Mo-Ti-Zr合金棒材的退火行為。結(jié)果表明：當(dāng)退火溫度低于1 000 ℃時(shí)，隨著退火溫度的升高，Mo-Ti-Zr合金硬度未急劇下降，抗拉強(qiáng)度和伸長率逐漸提高；經(jīng)900 ℃退火后，合金抗拉強(qiáng)度達(dá)到669 MPa，伸長率達(dá)到3.1%，獲得良好的綜合力學(xué)性能；當(dāng)退火溫度在800~1 000 ℃范圍內(nèi)時(shí)，Mo-Ti-Zr合金晶粒發(fā)生再結(jié)晶細(xì)化；旋鍛態(tài)Mo-Ti-Zr合金的斷口主要為穿晶解理斷裂，隨著退火溫度的提高，出現(xiàn)較多細(xì)晶粒的穿晶斷裂和沿晶斷裂。
關(guān)鍵字: Mo-Ti-Zr合金；冷等靜壓；高溫?zé)Y(jié)；旋鍛；退火；再結(jié)晶
（State Key laboratory of Powder Metallurgy, Central South University, Changsha 410083, China）
Abstract:The Mo-Ti-Zr alloy bars were prepared by cold isostatic pressing, high temperature sintering and direct rotary forging. The effects of the annealing temperature on the mechanical properties and microstructure of the alloy and the annealing behavior of this rotary forging Mo-Ti-Zr alloy bars deformed by 30% were investigated. The results show that, with increasing annealing temperature before 1 000 ℃, the hardness of the Mo-Ti-Zr alloy bars decreases slowly whereas the tensile strength and elongation increase. The tensile strength and elongation reach 669 MPa and 3.1%, respectively, at 900 ℃. The recrystallization of the Mo-Ti-Zr alloy bars occurs and the grains are refined at the annealing temperature of 800−1 000 ℃. For the rotary forging Mo-Ti-Zr alloy bars, its fracture is mainly a transcrystalline fracture type. The mixed type of transcrystalline fracture and intergranular fracture in the refined grains increases with increasing annealing temperature.
Key words: Mo-Ti-Zr alloy; cold isostatic pressing; high temperature sintering; rotary forging; annealing; recrystallization
