单晶高温合金螺旋选晶过程的数值模拟与实验研究 Ⅰ.引晶段  

SIMULATION AND EXPERIMENTAL STUDIES ON GRAIN SELECTION BEHAVIOR OF SINGLE CRYSTAL SUPERALLOY Ⅰ. Starter Block

作　　者：张航[1] 许庆彦[1] 孙长波[2] 戚翔[1] 唐宁[1] 柳百成[1] 

机构地区：[1]清华大学材料学院先进成形制造教育部重点实验室,北京100084 [2]沈阳黎明航空发动机(集团)有限责任公司,沈阳110043

出　　处：《金属学报》2013年第12期1508-1520,共13页Acta Metallurgica Sinica

基　　金：国家重点基础研究发展计划项目2011CB706801;国家自然科学基金项目51171089;国家科技重大专项项目2011ZX04014-052和2012ZX04012-011资助~~

摘　　要：从实验及模拟角度对比研究了引晶段的晶粒密度和取向随晶粒生长高度(研究位置距试样底面的高度)的变化规律,并给出了引晶段参数的设计准则.采用EBSD晶体取向成像技术获得了引晶段截面的晶粒形貌和取向极图;采用CA-FD方法,针对单晶定向凝固过程进行数理建模与仿真,实现了凝固过程的三维宏观温度场与微观组织生长的模拟计算.从宏、微观角度解释了定向凝固过程的晶粒竞争演化行为,为引晶段设计提供理论支持.The rapid development of advanced aero engine and industry gas turbine requires high performance of single crystal （SX） blade. Spiral selector is very important to produce SX blade, which includes starter block and spiral part. In this research, grain density changing and orientation deviating as the height of grain growth （the distance between section studied and the undersurface of the sample） increasing were studied by the experiment and simulation, and the designing rules for the starter block were given out. EBSD orientation mapping technology was used to get grains＇ morphology and orientation. Mathematical and physical models were built for the directional solidification process. Adopting CA FD method, the 3D macro temperature field of solidification process was calculated as well as grain growth. The properties of grains competitive growth and evolution process during directional solidification in starter block were analyzed based on macro and micro modeling results, and rules for grains competitive growth was explained, which provided theoretical supports for designing starter block.

关 键 词：螺旋选晶器 引晶段 数值模拟 晶粒取向 晶粒密度 

分 类 号：TG132[一般工业技术—材料科学与工程]