铸态T800合金及其焊层的组织和高温耐磨性能  

Microstructure and High-Temperature Fretting Wear Behavior of T800 Alloy in Casting and Cladding State

作　　者：李尚平[1] 骆合力[1] 曹栩[1] 张喜娥[1] 

机构地区：[1]钢铁研究总院,北京100081

出　　处：《稀有金属材料与工程》2013年第3期603-606,共4页Rare Metal Materials and Engineering

基　　金："十一五"军品配套项目

摘　　要：T800合金是一种优异的高温耐磨材料,广泛应用于涡轮叶冠表面强化。为了考察T800合金应用于涡轮叶冠时的最佳服役状态,对比研究了T800合金铸态及其堆焊层的微观组织、硬度和高温耐微动磨损性能,结果表明,铸态T800合金中Laves相的体积分数高、尺寸大,其硬度和高温耐微动磨损性更加优异。分析认为,在堆焊T800合金铸造焊丝的过程中,焊接基材中的合金元素混合进入了焊接溶池中,对焊层起到稀释作用,Laves相会发生溶解再析出反应,结果导致T800合金焊层中的Laves相体积分数大幅降低、尺寸变小,其硬度和耐磨性明显低于铸态T800合金。T800 alloy is a good wear-resistant coating material for tip shrouds of turbine blades operated at high temperature.In order to make clear the best serving state of T800 alloy,microstructure and high-temperature fretting wear behavior of T800 alloy in casting and cladding state were studied.During welding,alloying elements of K417G alloy substrate diffused into welding melting pool,which resulted in that there was a decrease in the alloying elements of the T800 clad.Laves phases were dissolved completely and then precipitated to form fine Laves phases in matrix during solidification.As a result,as-cast T800 possessed larger volume fraction and size of Laves phases,higher hardness and high-temperature fretting wear resistance than T800 cladding.

关 键 词：T800合金 微观组织 高温耐磨性 铸态 堆焊层 

分 类 号：TG146.4[一般工业技术—材料科学与工程]