定向凝固高温DZ125合金在热处理过程中碳化物的演化  

Carbides Evolution in Directionally Solidified Nickel-based Superalloy DZ125 during Heat Treatment

作　　者：田宁 闫化锦 赵国旗 孟宪林[2] 

机构地区：[1]贵州工程应用技术学院机械工程学院,贵州毕节551700 [2]沈阳工业大学材料科学与工程学院,辽宁沈阳110870

出　　处：《贵州工程应用技术学院学报》2017年第3期109-113,共5页Journal of Guizhou University Of Engineering Science

基　　金：贵州省普通高等学校煤化工过程装备与控制创新团队"煤化工过程装备可靠性";项目编号:黔教合人才团队字[2015]73;贵州省科学技术厅;毕节市科学技术局;贵州工程应用技术学院科学技术联合基金项目"DZ125合金在长寿命条件下的蠕变行为";项目编号:黔科合LH字[2015]7583

摘　　要：针对DZ125合金通过不同的热处理工艺,及组织形貌的观察,研究不同固溶温度对DZ125合金中碳化物演化规律的影响,结果表明,DZ125合金在不同状态及不同固溶温度下碳化物具有不同的形态。铸态DZ125时合金中为大块的MC碳化物,随着热处理的进行,固溶温度的提高,大块的MC碳化物逐渐分解为沿着晶界不连续析出的粒状M23C6型碳化物,可以抑制晶界滑移,提高合金的强度。经过标准热处理后合金枝晶间γ'相较为粗大,组织并不均匀。但经过高温固溶及时效处理后可消除合金在枝晶间区域存在中的粗大γ'相,使高体积分数细小立方γ'相均匀分布在枝晶间和枝晶干区域。By means of heat treatment at different regimes, and microstructure observations, an investigation has been made into the influence of solution temperature on the configuration evolution of carbides in DZ125 nickel-based superalloy. Results show that the carbides of DZ125 alloy have different microstructure at different states and different solid solution temperatures. Bulk-like MC-type carbide is distributed in the as-cast DZ125 superalloy. As the heat treatment goes on and the solution temperature rises, MC-type carbides transform into the particle-like M23C6 - type carbides precipitated discontinuously along grain boundaries, increase the strength of the alloy. After standard heat treatment, coarse cuboidal γ＇ precipitates distribute in the inter-dendrite regions, and the microstructure in the dendrite/inter-dendrite regions of the alloy is inhomogeneous. After solution treatment at higher temperatures and aging treatment, the coarse γ＇ precipitates in inter-dendrite regions are eliminated, and the high volume fraction of fine γ＇ precipitates distribute homogeneously in the dendrite / inter-dendrite regions.

关 键 词：固溶温度 组织结构 碳化物形态 蠕变 

分 类 号：TG113[金属学及工艺—物理冶金]