激光熔覆熔凝过程等离子体光信号的监测  

Monitoring Plasma Light in Laser Cladding and Melting

作　　者：洪蕾[1] 胡肇炜[1] 马保亮[1] 

机构地区：[1]上海海事大学物流工程学院,上海201306

出　　处：《中国激光》2011年第2期110-115,共6页Chinese Journal of Lasers

基　　金：教育部博士点基金(20093121120001);上海市自然科学基金(09ZR1421300);上海市教委科技重点项目(10ZZ99);上海市曙光计划(09SG47)资助课题

摘　　要：激光熔覆熔凝过程监测是激光熔覆层质量控制的方法之一。采用基模激光,以类似预置粉末的方式,在一定的工艺条件下对45#钢样件表面激光熔覆Ni60,并采用光电管传感器对此实验条件下熔覆再熔凝过程中产生的等离子体特征信号之一光信号进行检测,并分析了激光功率、扫描速度与等离子体蓝紫光信号强度的关系以及蓝紫光信号强度与熔覆层质量的关系。实验结果表明,在此实验条件下光强信号随激光功率增大而增大,但幅度不大。在激光功率未达到某特定值时,激光功率不变,扫描速度增加光强减小;当激光功率达到或超过此值后,激光功率一定时光强信号随着扫描速度的增加而增大;当光强信号处于1.7~2.5μW/cm2间且波动幅度较小时熔覆层质量好。分析表明当激光功率突破阈值后,扫描速度增加熔深变浅,用于材料气化的能量增加,因此蓝紫光强度增大。Laser cladding monitoring is one of the cladding layer quality controlling methods.In this paper,one of the characteristic signal of plasma optical signal has been detected by phototube.TEM00 laser has been used in experiments with two scans like powder present cladding.Powder use Ni60 and the base material is 45# steel.The relationship between blue-violet light intensity and laser power scan velocity,as well as the relevance between quality of layer and intensity have been discussed.The results indicate that while laser power grows,the intensity increases just at a low rate,and the intensity decreases as scan velocity increases when the power is lower than a definite value.But when the power is greater than the values,the intensity will rise as velocity increases.The quality of layer is improved greatly when the intensity value rangs from 1.7 to 2.5 μW/cm2 with a slight fluctuation.Analysis shows that when the laser power threshold is breaken,the scanning speed increases and penetration shallows,and energy for material vaporizing increases,so intensity of blue-violet light grows.

关 键 词：激光技术 等离子体 蓝紫光 实时监测 

分 类 号：TN247[电子电信—物理电子学] TN249