激光熔凝对304奥氏体不锈钢拉伸力学性能的影响  

Effect of Laser Melting on Tensile Mechanical Properties of 304 Austenitic Stainless Steel

作　　者：王源蜜[1] 邱长军[1] 何彬[1] 刘武[1] 

机构地区：[1]南华大学机械工程学院,湖南衡阳421001

出　　处：《热加工工艺》2013年第2期109-112,共4页Hot Working Technology

摘　　要：采用5 kW横流CO2激光器,分别在常温空气冷却、冰水快速冷却条件下对304奥氏体不锈钢的上下表面进行熔凝试验,并对比分析其显微组织和拉伸力学性能。结果表明:经激光熔凝处理后,熔凝层组织形态由里及表依次为平面晶、胞状晶、树枝晶和等轴晶;组织明显得到细化,常温空气冷却和冰水快速冷却的熔凝层组织分别比基体组织细化约14倍和18倍;经两种不同的处理方式得到的试件,其拉伸力学性能均得到增强,且随熔凝层冷却速度的增加,相应的拉伸力学性能指标提高的幅度也增加。其中,经冰水快速冷却激光熔凝处理后的试件屈服强度、抗拉强度和伸长率分别可提高约22.4%、16.4%和15.7%The top surface and bottom surface of 304 austenitic stainless steel were melted using 5 kW continuous wave CO2 laser. The microstructure and tensile mechanical properties of laser melted layer cooled in room temperature air and cooled with ice water were compared. The research results show that the laser melting layer structure of the melted zone consists of plane crystal, cellular crystal, dendrite and equiaxed crystal from the bottom to the surface. The microstructure is obviously refined, microstructure of laser melted layer cooled in room temperature air and cooled in chilled water is refined 14 and 18 times than matrix microstructure. The two kinds of different processing ways were used to get the specimens, its tensile mechanical properties were improved, and enhancement of the tensile mechanical properties index increases with the increase of cooling rate of the melting layer. Among them, laser melting treatment 304 austenitic stainless steel in the state of cooling with ice water, their yield strength, tensile strength and elongation rate can be increased to 22.4%, 16.4% and 15.7%, respectively.

关 键 词：304奥氏体不锈钢 激光熔凝 细化组织 拉伸力学性能 

分 类 号：TG174[金属学及工艺—金属表面处理]