(中北大學 材料科學與工程學院，太原 030051)
摘 要: 基于微觀相場法研究不同彈性畸變能對Ni75Al5V20合金中L12相沉淀過程的影響。結果表明：雖然彈性畸變能不同，Ni75Al5V20合金在溫度為1250 K下沉淀時的顯微組織演化過程都可大概分為4個階段，但也有不同之處；在早期沉淀析出的L12相中，V原子的占位要遠大于Al原子的占位，最終，隨著彈性畸變能的增大，在L12相中Al原子的占位概率降低，V原子的占位概率增大。在生成化學計量比的L12有序相時，Al原子由L12相邊界逐漸向其內部擴散，而V原子則與之相反，且各原子越靠近L12相的邊界擴散速度越快，反之越慢。
關鍵字: Ni75Al5V20合金；微觀相場；彈性畸變能；占位概率；L12相
（College of Materials Science and Engineering, North University of China, Taiyuan 030051, China）
Abstract:The precipitation process of L12 phase in Ni75Al5V20 alloy was mainly simulated by using the microscopic phase-field kinetic mode. The results demonstrate that the process of microscopic morphology evolution can be divided into four stages for Ni75Al5V20 alloy at 1250 K on different elastic strain energy, but there also are some different points. The occupation probability of Al atom is greater than V atom in early precipitation of L12 phase when the elastic strain energy is existent. Eventually, with increasing the elastic strain energy, the occupation probability of Al atom reduces and the occupation probability of V atom increases in L12 phase. When stoichiometric L12 ordered phase generates, the Al atoms gradually diffuse from L12 phase boundaries to its internal, meanwhile, the V atoms gradually diffuse from L12 phase internal to its boundaries, and the atoms in L12 phase are more closer to boundary, their diffusion speed becomes more faster, conversely becomes more slowly.
Key words: Ni75Al5V20 alloy; microscopic phase-field; elastic strain energy; occupation probability; L12 phase
