不同变形量下中碳钢马氏体温变形组织演变研究  

Microstructure Evolution of Medium Carbon Steel Martensite during Warm Deformation with Different Deformation Degrees

作　　者：饶广[1] 汪建敏[1] 樊博闻 

机构地区：[1]江苏大学材料科学与工程学院,江苏镇江212013

出　　处：《热加工工艺》2017年第7期97-100,共4页Hot Working Technology

摘　　要：在变形温度650℃和应变速率0.01 s^(-1)条件下,采用Gleeble3800热模拟试验机研究了45钢温变形的马氏体组织演变规律。结果表明:在温变形初期,微观组织保持着板条状形貌,渗碳体球化率较低;当变形量为60%时,再结晶晶粒基本等轴化,渗碳体球化率显著增大,但晶界处渗碳体粒子均匀性差;随着变形量增加,平均铁素体晶粒尺寸先减少后增大,渗碳体球化率基本不变;当变形量为70%时,平均铁素体晶粒尺寸达到最小,铁素体发生完全动态再结晶,获得一种微米级等轴铁素体晶粒和纳米级球化渗碳体粒子均匀分布的超细化组织。At deformation temperature of 650 ℃ and strain rate of 0.01s-1, the microstructure evolution of martensite in 45 steel during warm deformation was studied by Gleeble-3800 thermal simulation machine. The results indicate that, at the early stage of warm deformation, microstructure maintains lath morphology and the spheroidization rate of cementite is lower; when the deformation is 60%, recrystallized grains are mainly equiaxial, the spheroidization rate of cementite increases significantly, but the uniformity of cementite particles at grain boundary is poor;with the increase of deformation, average ferdte grain size decreases firstly and then increases, the spheroidizafion rate of cementite is mainly unchanged; when the deformation is 70%, the average ferrite grain size is the smallest, full dynamic recrystallization of ferrite occurs, which obtains the ultra-fine microstructure of uniform distribution of micron grade equal axial ferrite grain and nano grade spherical eementite particles.

关 键 词：马氏体 温变形 变形量 动态再结晶 超细组织 

分 类 号：TG316[金属学及工艺—金属压力加工] TG142.1[一般工业技术—材料科学与工程]