基材晶体取向对激光定向凝固单晶显微组织的影响  

Influences of Crystallography Orientation of Substrate on Laser Directional Solidification Single Crystal Microstructure

作　　者：冯莉萍[1] 黄卫东[2] 林鑫[2] 杨海欧[2] 陈大融[1] 

机构地区：[1]清华大学摩擦学国家重点实验室,北京100084 [2]西北工业大学凝固技术国家重点实验室,西安710072

出　　处：《应用激光》2004年第3期135-138,共4页Applied Laser

基　　金：973国家重点基础研究发展规划 (No .G2 0 0 0 0 6 72 0 5 - 3);86 3国家高技术研究发展计划 (No .0 0 1AA70 30 2 0 )资助

摘　　要：利用Rene95合金在DD3单晶基材的 (0 0 1)面、(10 0 )面和与 (0 0 1)面夹角分别为 4 5°和 2 2 .5°的晶面上进行激光多层涂覆 ,研究了基材晶体取向对单晶显微组织的影响规律。研究表明 ,当实验在基材的择优晶面 { 0 0 1}上进行 ,涂层的组织为定向凝固柱状晶 ,晶体取向与基材的晶体取向相一致 ,一次间距约为 10 μm ,二次臂退化。当实验在基材的非择优晶面 (与(0 0 1)面的夹角θ分别为 4 5°和 2 2 .5°的晶面 )上进行 ,涂层的晶体取向仍然与基材的晶体取向一致 ,但枝晶二次臂出现 ,θ为4 5°角的晶面与 2 2 .5°角的晶面相比 ,枝晶二次臂的发展不平衡性加大。Laser multi-layer cladding experiments were performed on different crystallographic planes of DD3 single crystal using Rene95 powder as cladding material. The crystal planes are (001),(100) and planes deviated 45 ° and 22.5 ° from the (001). Influences of the crystallographic orientation of DD3 on the single crystal microstructure of the cladding layer were investigated. Results show that when experiments were performed on the preferred crystal plane {001},crystallographic orientation of the cladding layer is identical with that of the substrate. While performed on the crystallographic planes deviated θ deg (45 ° and 22.5 °) from the preferred ones,the secondary dendrites appear. When the θ is 45 °,the secondary dendrites developed more unbalanced than that the deviated θ is 22.5 °.

关 键 词：激光多层涂覆 基材晶体取向 单晶显微组织 定向凝固 外延生长 

分 类 号：O552.6[理学—热学与物质分子运动论]