(西北工業(yè)大學 凝固技術國家重點實驗室，西安 710072)
摘 要: 采用定量分析方法研究高溫變形參數(shù)如變形溫度、應變速率和變形程度對Ti2AlNb基合金在O+B2兩相區(qū)片層組織球化行為的影響。結果表明：變形溫度影響Ti2AlNb基合金的相組成和尺寸，隨溫度升高，兩相區(qū)中O相逐漸轉(zhuǎn)變?yōu)榛wB2相，并變短、變粗。應變速率的減小可以促進合金元素的擴散，有利于片層組織的球化。變形量對合金片層組織的球化促進作用最大，片層組織球化的臨界變形量在0.3~0.5之間，變形量為0.7時合金片層組織幾乎完全球化。
關鍵字: Ti2AlNb基合金；變形參數(shù)；片層組織；球化行為
（State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072, China）
Abstract:The effects of deformation parameters, including deformation temperature, strain rate, and deformation degree, on the globularization behavior of lamellar structures of Ti2AlNb based alloys with initial lamellar O were studied by isothermal compression in O+B2 filed through quantitative metallography. The results show that the phase composition and size are affected by the deformation temperature. In two-phase filed, the initial lamellar O transforms to B2 phase, and lamellar O becomes shorter and thicker with increasing the deformation temperature. The decrease of the strain rate is propitious to the diffusion of the microstructural composition, which improves the globularization of the initial lamellar O. Deformation degree exerts the greatest impact on the globularization of the lamellar O. The critical deformation degree is 0.3-0.5 and nearly all the lamellae are globularized when the deformation degree is 0.7.
Key words: Ti2AlNb based alloy; deformation parameter; lamellar structure; globularization behavior
