(上海交通大學(xué) 材料科學(xué)與工程學(xué)院，上海 200240)
摘 要: 采用電子背散射衍射(EBSD)對Ti-23Nb-0.7Ta-2Zr-1.2O(摩爾分?jǐn)?shù)，%)合金的冷旋鍛變形組織和退火組織進(jìn)行了研究。結(jié)果表明：Ti-23Nb-0.7Ta-2Zr-1.2O合金的變形組織中包含高密度的小角晶界，合金具有與棒材軸向平行的強(qiáng)烈<110>絲織構(gòu)；在退火過程中，合金中的小角晶界密度逐漸降低，大角晶界數(shù)量逐漸增多并最終成為主要晶界；在退火過程初期，合金中出現(xiàn)了大量細(xì)小晶粒，且隨著退火時間的增加，這些晶粒逐漸通過消耗變形組織長大，晶粒取向逐漸分散，表明Ti-23Nb-0.7Ta-2Zr-1.2O合金的再結(jié)晶通過傳統(tǒng)的形核長大機(jī)制進(jìn)行。
關(guān)鍵字: 鈦合金；再結(jié)晶；顯微組織；織構(gòu)
（School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China）
Abstract:The microstructures of Ti-23Nb-0.7Ta-2Zr-1.2O (mole fraction, %) alloy under cold-swaged and annealed condition were investigated by electron back-scattering electron diffractometry (BSD). The results show that the microstructures of Ti-23Nb-0.7Ta-2Zr-1.2O alloy deformed contain high density low angle grain boundaries, the alloy has distinctive <110> fiber texture paralleling the axial direction of stick. During annealing of the cold-swaged alloy, the low-angle grain boundaries gradually disappear and the high-angle grain boundaries become predominant. At early stage of annealing, the clusters of fine grains appear in the alloy. With the increase of the annealing time, those grains grow gradually at the expense of deformed microstructure. Meanwhile, the orientations of those grains gradually become dispersed, which indicates that the recrystallization of Ti-23Nb-0.7Ta-2Zr-1.2O alloy is achieved by the traditional mechanism of nucleation and growth of new grains.
Key words: titanium alloy; recrystallization; microstructure; texture
