Laves相RM2(R=稀土，M=过渡金属)合金是目前最重要的一类磁致伸缩材料，被广泛应用于换能器和传感器等领域。在Laves相RM2合金中发现铁磁MPB准同型相界之后(2010年)，在MPB附近开发具有大磁致伸缩效应的合金成为功能材料研究领域的研究热点之一。RM2合金可能具有超过100种的不同合金成分，并且相界两侧晶格畸变非常小，因此利用实验手段测定铁磁MPB是一项巨大的挑战。利用第一性原理高通量计算，能够得到大量不同成分合金的铁磁相稳态结构，及其微小的晶格畸变。本项目拟在前期研究成果的基础上，以第一性原理高通量计算Laves相RM2合金中MPB准同型相界为出发点，结合Landau相变唯象理论，分析MPB准同型相界附近的相变路径对磁致伸缩效应的影响机理，揭示MPB准同型相界理论和SRT自旋重取向相变理论在RM2合金中的适用范围。本项目的研究对于开发高性能Laves相磁致伸缩材料具有重要的

RM2 alloy (R=rare-earth, M=transition metal) with Laves phase is one of the most important magnetostrictive materials, which is widely employed in transduces and sensors. After magnetic MPB (morphotropic phase boundary) was found in RM2 alloy (2010), the investigation of giant magnetostrictive effect near MPB attracts great interests of researchers. However, there are more than 100 RM2 alloys, and the lattice distortion on the sides of MPB is very small. Therefore, it is difficult to detect the MPB experimentally, but to be detected by high flux calculation efficiently. Based on our previous research, we propose high flux first-principle calculation to search The MPB in RM2 alloy with Laves phase to study the influence of MPB on magnetostriction in Laves –structure RM2 alloy. Moreover, the Landau phenomenological theory would build to investigate the magnetostrictive effect. Finally, the applicability of MPB and SRT (spin reorientation transition) theory in Laves-structure RM2 alloy would be discussed. Our work will shed light develop high-performance Laves-structure magnetostrictive materials.