(中南大學(xué) 材料科學(xué)與工程學(xué)院, 長(zhǎng)沙 410083)
摘 要: 采用相場(chǎng)模型對(duì)外加應(yīng)力場(chǎng)對(duì)共格沉淀析出過(guò)程的微觀結(jié)構(gòu)演化進(jìn)行模擬研究， 在外加應(yīng)力場(chǎng)作用下， 非均勻彈性模量系統(tǒng)沉淀相的析出過(guò)程發(fā)生重大的變化， 粒子沿彈性軟方向呈各向異性析出， 這種各向異性生長(zhǎng)與外加應(yīng)力、 點(diǎn)陣錯(cuò)配度的符號(hào)以及非均勻模量差的符號(hào)有關(guān)。 采用雙級(jí)時(shí)效模擬方式時(shí)， 外加應(yīng)力場(chǎng)對(duì)析出相的成核及生長(zhǎng)階段均有影響， 只是影響程度與析出相自身的點(diǎn)陣錯(cuò)配度有關(guān)。 對(duì)適當(dāng)?shù)捏w系采用應(yīng)力時(shí)效的方式可能是實(shí)現(xiàn)除分子束外延技術(shù)之外的一種全新的制備超晶格微結(jié)構(gòu)的方法。
關(guān)鍵字: 點(diǎn)陣錯(cuò)配度; 外加應(yīng)力; 應(yīng)力時(shí)效; 計(jì)算機(jī)模擬
ZHOU Ming, LIU Zu-yao, LI Jian, CHEN Zhi-guo
（ School of Materials Science and Engineering, Central South University,
Changsha 410083, China）
Abstract: The effect of external stress on the microstructure evolution of alloys containing coherent precipitates was studied by phase field model. In an elastically inhomogeneous system, an applied strain can result in the selective growth of precipitates with homogeneous strain field, which depends on the signs of the applied strain, lattice misfit and the elastic inhomogeneity. Both nucleation and growth are affected by the external stress by two-step aging simulation, but the effect degree depends on lattice misfit. The stress aging technology can be used to obtain superlattice structure for some special systems.
Key words: lattice misfit; external stress; stress aging; computer simulation
