GH4169G合金锻件条带缺陷微观检测及改进  

Microscopic Inspection and Improvement of GH4169GAlloy Forging Banded Structure Defects

作　　者：孙凯 蔺虹宾[1,2] 何跃斌 苗景国[1,2] Sun Kai;Lin Hongbin;He Yuebin;Miao Jingguo(Engineering Laboratory of Aviation Materials Testing and Stamp Forging Technology in Sichuan Province;Sichuan Engineering Technical Collage)

机构地区：[1]四川省航空材料检测与模锻工艺技术工程实验室,四川德阳618000 [2]四川工程职业技术学院

出　　处：《特种铸造及有色合金》2020年第6期694-696,共3页Special Casting & Nonferrous Alloys

基　　金：德阳市重点科技计划资助项目(2018SZY067);四川工程职业技术学院校级科研基金资助项目(YJ2019KJ-21)。

摘　　要：GH4169G合金锻件在低倍组织检验时出现明暗相间的条带缺陷,对其进行微观检验。结果表明,条带暗处的δ-Ni3Nb相较正常部位明显富集,晶粒度偏大,条带组织的出现与碳化物、碳氮化物的偏聚无关。借助JMatPro对GH4169G合金凝固过程的相转变规律进行模拟计算,发现合金中Nb元素的平衡分配系数最小,为0.19,容易形成成分偏析,这是形成明暗条带缺陷的主要原因。将合金锭均匀化热处理由原来2段改为3段后,即1120℃×15h+1160℃×30h+1190℃×60h,合金条带缺陷消失。The GH4169Galloy forgings have light and dark banded defects during low power inspection,which was observed through micro metallography.The results reveal that theδ-Ni3Nb phase is segregated in banding defect with coarse grain size,in addition,it is independent on the segregation of carbide and carbonitride.The JMatPro software was used to simulate the phase transition of GH4169Galloy during solidification process.The results reveal that the equilibrium distribution coefficient of Nb in the alloy is 0.19,so composition segregation is easily formed,which are responsible for dark and light banded structure formed.The homogenizing treatment of alloy is modified from two-stage into the three-stage of 1120℃×15h、1160℃×30hand 1190℃×60h,so the banded structure is eliminated.

关 键 词：GH4169G合金 条带缺陷 δ-Ni3Nb相 Nb偏析 

分 类 号：TG113.1[金属学及工艺—物理冶金] TG146.15[金属学及工艺—金属学]