定向凝固和单晶高温合金再结晶影响因素

Influencing Factors of Recrystallization of Directionally Solidified and Single Crystal Superalloys

定向凝固和单晶高温合金具有优异的高温力学性能,是制造先进航空发动机涡轮叶片的主要材料。定向凝固和单晶高温合金的优异性能主要来源于消除了与应力轴垂直的晶界,而再结晶的出现会显著降低合金的高温力学性能。本文基于近年来国内外对于定向凝固和单晶高温合金再结晶行为的研究,系统分析和总结了定向凝固和单晶高温合金再结晶的主要影响因素,包括热处理温度、热处理时间、第二相粒子、变形温度、高温氧化、以及表面处理工艺等因素对再结晶的影响。

With excellent high-temperature mechanical properties, directionally solidiifed（DS） and single crystal（SC） superalloys have become the most important materials for turbine blades of advanced aero-engines. The excellent mechanical properties of DS and SC superalloys mainly result from the elimination of grain boundaries perpendicular to the main stress axis. Since recrystallized grains may introduce disadvantageous orientations and high-angle grain boundaries, they will dramatically reduce the mechanical properties of DS and SC components. In the present work, the main inlfuencing factors of recrystallization of DS and SC superalloys were analyzed and summarized, including annealing temperature, annealing time, second-phase particles, deformation temperature, high-temperature oxidation and surface treating processes.