光纤激光器功率对Cr12MoV钢表面淬火组织与性能的影响  

Effects of Fiber Laser Power on the Microstructure and Properties of Cr12MoV Steel

作　　者：何力佳[1] 

机构地区：[1]辽宁工业大学材料科学与工程学院,锦州121001

出　　处：《材料导报》2014年第20期91-93,共3页Materials Reports

基　　金：辽宁省自然科学基金(2013020086);辽宁省教育厅项目(L2012220);2013年中央与地方高校共建项目

摘　　要：由于光纤激光的良好光束质量,光纤激光器在金属材料表面强化方面的应用日益引起学者的重视。使用YLS-3000W光纤激光器对Cr12MoV冷作模具钢进行激光表面淬火处理的工艺试验,研究了不同工艺参数对硬化层深度和显微硬度的影响及硬化层显微组织特征。结果表明,Cr12MoV表面经光纤激光表面淬火后得到淬火层、过渡层和基体3层不同的组织。淬火层的晶粒细小,由隐晶马氏体、弥散分布的碳化物组成。过渡层由马氏体及弥散分布的碳化物和残留奥氏体组成。在扫描速度和离焦量一定的条件下,相变硬化层深度随光纤激光功率的增大而增加。在最佳工艺(光纤激光功率900W,扫描速度0.3m/s,离焦量-4mm)条件下,硬化层平均硬度达609HV。分析认为光纤激光淬火造成的组织细化和过饱和的隐晶马氏体的形成是硬度提高的主要原因。Due to excellent beam quality of fiber laser, the application of fiber laser on the surface strengthening of metal attracts the attention of researchers increasingly. By using YLS-3000W fiber laser, the surface quenching experiment of Cr12MoV steel was investigated in detail, and the effects of different processing parameters on the hardening depth, micro-hardness as well as the microstructure evolution was studied. The experimental results show that the three-layer structure was found after fiber laser surface hardening, which is composed of hardened layer, the transition layer and substrate. The hardened layer has refined grains, which is composed of cryptocrystalline Martensite and dispersed carbides. The transition layer is composed of Martensite, dispersed carbides and retained Austenite. Under the fixed scanning speed and defocusing amount, phase transformation hardening layer depth increases with the increase of laser power. The average hardness reaches 609HV under the optimal parameters （laser power 900 W, scanning speed 0. 3 m/s and off-focus length --4 mm）. The hardness enhancement of the hardened layer is attributed to the grain refining and the formation of supersaturated hidden-crystal martensite by laser quenching.

关 键 词：光纤激光器 激光淬火 工艺参数 显微组织 

分 类 号：TG142.22[一般工业技术—材料科学与工程]