表面激光相变硬化45钢的冲击韧性及其断裂机理(英文)  

Impact Toughness and Fracture Mechanism of the Surface Laser Hardened Components of 45 Steel

作　　者：雷声[1] 任静明[1] 石超[1] 朱绍锋[1] 刘牛[1] 陈香[1] 

机构地区：[1]安徽建筑大学机械与电气工程学院,安徽合肥230022

出　　处：《激光与光电子学进展》2015年第1期168-172,共5页Laser & Optoelectronics Progress

基　　金：安徽省科技厅2013年度第二批科技计划项目(1305073037);安徽省教育厅自然科学重点资助项目(KJ2012Z051,2012SQRL131)

摘　　要：用激光相变硬化技术制备45钢冲击试样(V型槽口),并对试样进行冲击试验,研究了激光功率对45钢激光表面硬化冲击试样冲击韧性值的影响。通过光学显微镜和扫描电镜(SEM)观察了试样表面显微组织和断口的形貌特征。对常规热处理试样和激光表面硬化试样断口进行对比分析。结果表明,常规热处理试样断裂后断裂表面均表现出韧性断裂后的韧窝特征,激光硬化层起裂区呈现脆性断裂特征。经激光硬化后钢件的断裂机制发生改变,导致激光硬化试样冲击韧性值的下降。45钢激光表面硬化冲击试样冲击韧性值随着激光功率增加而逐渐减少。In this study, the impact of laser quenching on 45 steel （V-shaped notch） is researched and the effect of laser power on the fracture toughness is investigated. The specimens surface and fracture morphology are examined by optical microscope and scanning electronic microscope （SEM）. Dimple characteristics are observed on the fracture surface of original specimens. As comparison, there are brittle fracture characteristics in the crack initiation zone of laser hardened specimens. Our results indicate that the fracture toughness of laser hardened specimen is reduced. Moreover, the surface fracture toughness decreases with increasing of the laser power.

关 键 词：激光技术 激光相变硬化 冲击韧性 脆性 断裂 

分 类 号：TG302[金属学及工艺—金属压力加工]