奥氏体化温度对GCr15钢球化效果的影响  

Effect of austenitizing temperature on spheroidization of GCr15 steel

作　　者：李振兴[1] 李长生[1] 李忠之 乔兵[2] 

机构地区：[1]东北大学轧制技术及连轧自动化国家重点实验室,辽宁沈阳110819 [2]东北特殊钢集团有限责任公司,辽宁大连116105

出　　处：《金属热处理》2015年第5期61-65,共5页Heat Treatment of Metals

基　　金：国家高技术研究发展计划(863计划)(2012AA03A503);国家自然科学基金(51174057;51274062);高等学校博士学科点专项科研基金(20130042110040)

摘　　要：用管式炉对GCr15钢球化退火工艺进行模拟,研究了奥氏体化温度对碳化物球化效果的影响。利用XRD和TEM分析了碳化物的种类,采用电子探针观察了显微组织,并利用Image-Pro Plus和Photoshop软件对碳化物的平均直径,单位面积内的碳化物数目以及碳化物的平均粒间距进行了统计。结果表明,球化状态GCr15钢中的碳化物均为M3C。奥氏体化温度在760~880℃内变化时,随着奥氏体化温度的升高,碳化物的平均直径在0.35~0.45μm内先略微减小后逐渐增加,单位面积内的碳化物数目逐渐减少,碳化物的平均粒间距逐渐增加,试样的硬度逐渐减小。拟合发现,维氏硬度和单位体积内铁素体-碳化物的界面面积呈正比,拟合方程为HV=17.4S+190。为得到良好的球化组织,奥氏体化温度应控制在800℃左右。Spheroidizing process of GCr15 steel was simulated in pipe furnace and the effect of austenitizing temperature on spheroidization was investigated. The XRD and TEM were used to analyze the kinds of carbides and the electronic probe was used to observe the microstructure. The mean diameter,the number of carbides per unit area and mean carbides particle spacing were counted by Image-Pro Plus and Photoshop software. The results show that carbides in spheroidized GCr15 steel belong to M3C; with the increase of austenitizing temperature from 760 ℃ to 880 ℃,the mean diameter of carbides,which ranges from 0. 35 μm to 0. 45 μm,decreases first and then increases,the number of carbides per unit area decreases gradually,the carbides particle spacing increases and the hardness decreases. It is also found that the Vickers hardness is proportional to the area of ferrite-carbide interface,the fitting equation is HV = 17. 4S + 190. In order to get good spheroidized structure,the austenitizing temperature should be controlled about 800 ℃.

关 键 词：GCR15钢 奥氏体化温度 球化退火 碳化物 硬度 

分 类 号：TG156.2[金属学及工艺—热处理]