工艺参数对Rene80激光定向凝固组影响研究  

Research of the Influence of Processing Parameter on Laser Directional Solidification Structure

作　　者：张冬云[1] 李志波[1] 赵恒[1] 左铁钏[1] 

机构地区：[1]北京工业大学激光工程研究院,北京100124

出　　处：《应用激光》2013年第2期113-118,共6页Applied Laser

基　　金：973国家重点基础研究发展计划资助项目(项目编号:2011CB606305-3)

摘　　要：定向凝固组织由于显著减少了垂直于应力轴的横向晶界,使合金具有优异的高温蠕变及持久性能,因而在航空发动机涡轮叶片的制造中使用越来越广泛。采用激光金属外延成形(E-LMF)方法,进行了工艺参数对Rene80镍基高温合金定向凝固组织影响的研究。研究内容包括工艺参数对成形件定向凝固组织类型、枝晶间距和转向枝晶区高度的影响规律以及基材晶体取向对定向凝固枝晶形貌的影响。结果表明,枝晶一次间距随激光功率的增加而增大,随扫描速度的增加而减小;转向枝晶区高度随激光功率的提高而增大,随扫描速度的提高而减小;只有基材晶体取向与择优取向相近或一致才能得到外延定向连续生长的凝固组织。Directional solidification microstructure reduces significantly the amount of transverse grain boundary perpendicular to the main stress axis, what makes itself with excellent high temperature creep and lasting property and more and more applications in manufacturing of aeroengine turbine blade are found. The investigation under the effects of technological parameters on directional solidification micrestructure for Rene80 by E-LMF was carried out. The research includes the influence rules of technological parameters on directional solidification structure style, primary dendrite arm spacing and the height of orientation changed dendrite area and the effect of substrate crystal orientation on dendrite morphology of directional solidification. The results show that primary dendrite arm spacing increases with the increase of laser power and decreases with scanning speed; the height of orientation changed dendrite area increases with the increase of laser power and decrease with the increase of canning speed; only when the substrate crystal orientation and preferred orientation is similar or consistent the solidification structure of continuous epitaxial directional growth could obtained.

关 键 词：激光金属外延成形 定向凝固 显微组织 转向枝晶 

分 类 号：TG146[一般工业技术—材料科学与工程] TG113[金属学及工艺—金属材料]