0Cr13Ni4Mo马氏体不锈钢表层的喷丸强化  

SHOT PEENING INDUCED STRENGTHENING OF THE SURFACE LAYER OF MARTENSITE STAINLESS STEEL 0Cr13Ni4Mo

作　　者：马素媛[1] 陈瑞[2] 贺笑春[1] 李家宝[1] 郝学卓[2] 

机构地区：[1]中国科学院金属研究所沈阳材料科学国家(联合)实验室,沈阳110016 [2]沈阳铸造研究所,沈阳110021

出　　处：《金属学报》2005年第1期28-32,共5页Acta Metallurgica Sinica

基　　金：国家自然科学基金资助项目59971061~~

摘　　要：对经1000℃正火和600℃回火的水轮机过流部件用钢0Cr13Ni4Mo进行喷丸处理,测量了喷丸影响层的显微硬度、X射线衍射线半高宽和屈服强度等参量的沿层深分布,并计算了相应的晶块尺寸、微观应变和位错密度等微观结构参量.结果表明,该影响层以显微硬度和屈服强度表征的组织强化效应显著,显微硬度和屈服强度提高是由于晶块细化、微观应变和位错密度增大造成的.喷丸影响层不同部位的显微硬度与条件屈服点之比约为3.37;半高宽与显微硬度之间存在两段式线性关系:Hw=2.07×10-3 HV-3.47(HV<2835 MPa)和Hw=1.14×10-3 HV-0.81(HV>2835 MPa),条件屈服点与位错密度的平方根之间存在Bailey-Hirsch线性关系: σ0.2S=551+16.2×10-4ρ1/2.A low carbon martensite stainless steel 0Cr13Ni4Mo normalized at 1000 degreesC and tempered at 600 degreesC, used in the guide stream assemblies of water turbine, was treated with shot peening. The depth distributions of microhardness, half width value of X-ray diffraction profiles and yield strength in the shot-peening affected layer were measured. Correspondingly, the depth distributions of microstructure parameters, such as subgrain size, microstrain and dislocation density, in this layer were calculated. The experimental results indicate that the structure strengthening charactered by microhardness and yield strength is prominent. The subgrain size decreases, and the microstrain and dislocation density increase in the shot-peening affected layer, which results in the increase of the microhardness and yield strength. The ratios of microhardness to proof stress are all about 3.37 in different depths of the affected layer. The relation of the half-width value, H-w, and microhardness, HV, in the layer is linear, which is composed of two beelines: if HV less than or equal to 2835 MPa, H-w = 2.07 x 10(-3) x HV-3.47, and if HV > 2835 MPa, H-w = 1.14 x 10(-3) HV-0.81. The relation of the proof stress, sigma(0.2)(s), and square root of dislocation density, rho1/2 in the layer is also linear: sigma(0.2)(s) = 551 + 16.2 x 10(-4) rho(1/2).

关 键 词：马氏体不锈钢 喷丸影响层 组织强化 屈服强度 位错密度 

分 类 号：TG142.7[一般工业技术—材料科学与工程]