线能量对G5钢粗晶区组织性能影响的热模拟研究  

Thermal Simulation on Effect of Line Energy on Microstructure and Properties of Coarse Grained Region of G5 Steel

作　　者：李光普[1] 陈冰泉[1] 黄永溪 汤剑[1] 

机构地区：[1]武汉理工大学华夏学院,湖北武汉430223 [2]中钢邢台机械轧辊有限公司修复公司,河北邢台054025

出　　处：《热加工工艺》2016年第9期240-242,共3页Hot Working Technology

摘　　要：利用热模拟试验机Gleeble3500模拟了G5钢在单、双丝埋弧焊时四种线能量下的粗晶区组织。通过冲击试验、断口分析、金相观察、硬度试验和滑动磨损试验,对模拟粗晶区的组织和性能进行了研究。研究显示:随线能量的增大模拟粗晶区晶粒变大,该区组织主要为马氏体+残奥+碳化物,当线能量≥39 kJ/cm时还出现贝氏体。四种线能量下的模拟粗晶区冲击功均很低,冲击试样断口均为晶粒状脆性断口,断口启裂处微观断裂机制均以沿晶断裂为主。线能量为25 kJ/cm时模拟粗晶区的硬度和耐磨性最高,进一步增加线能量硬度和耐磨性略有下降。可以认为,线能量对模拟粗晶区的组织有一定影响,但对该区性能影响不大。With the aid of thermal simulated test machine Gleeble3500, the microstructure of coarse grained region of G5 steel at four types of heat inputs of one-wire and two-wire submerged arc welding was simulated. By impact test, fractured surface analysis, metallographic observation, hardness test and sliding wear test, the microstructure and properties of simulated coarse grained region were studied. The results show that： the grain of simulated coarse grained region grows with heat input increasing The structure of the region is martensite ＋retained austenite ＋carbide mainly, and bainite appears in the regiion when heat input is higher than 39 KJ/cm. The impact work of the simulated coarse grained region are all very low under four kinds of heat input. The impact fractures are all brittle, and the micro-fracture mechanism at the point of initiation break is inter-granular fracture principally. The simulated coarse grained region has the highst hardness and wearing resistant as heat input is 25 KJ/cm, the, but the hardness and wearing resistant decrease slightly when the heat input furtherly. It can be considered that high heat input has certain influence on the microstructure of simulated coarse grained region, but has no obvious influence on the properties of the zone.

关 键 词：热模拟 粗晶区 焊接热循环 

分 类 号：TG422.3[金属学及工艺—焊接]