316L不锈钢光纤激光切割工艺优化研究

Research on Optimization of Fiber Laser Cutting Technology of 316L Stainless Steel

316L不锈钢以其优良的性能广泛应用于生产生活中,随着316L不锈钢应用的不断加深,采用激光切割316L精密零件日益增多。建立同时满足基于保护气氛的汽化切割条件的材料物性、成型参数与切缝宽度之间的数学模型;采用脉冲激光切割316L不锈钢薄板,通过体式显微镜观察、测量切缝形貌,验证建立计算模型的准确性,分析切缝缺陷产生的原因。结果表明,切缝宽度数学计算模型的平均相对误差为8.5%,计算精度较高,具有实际工程应用价值;切缝宽度与光斑直径、激光功率、吸收率成正相关关系,与切割速度、板厚、比热、熔化焓、气化焓成负相关关系;切缝缺陷主要由重铸层、刮渣和波浪条纹组成,重铸层中有较多热裂纹,刮渣物主要是由圆形和条形金属颗粒物组成。

316Lstainless steel is widely used in production and living for its excellent properties.With the deepening application of 316 Lstainless steel,the cases of laser cutting 316 Lprecision parts are rapidly increasing.In this paper,the mathematical model among material properties,forming parameters and the kerf width of the vaporization cutting conditions based on the protective atmosphere is established.The 316 Lstainless steel sheet was cut using pulsed laser.Its kerf morphology was observed and measured by microscope.The mathematical model accuracy was verified.The reason of generated kerf defect was analyzed.The results show that the average relative error of mathematical model of kerf width is 8.5%,with high calculation accuracy and practical value in engineering application.There is a positive correlation among kerf width,laser spot diameter,laser power and absorption rate,and a negative correlation among kerf width,cutting speed,sheet thickness,specific heat,melting enthalpy and vaporization enthalpy.The kerf defect is mainly composed of recast layer,scraping slag and wave pattern.There is some hot crack in recast layer.The scraping slag is mainly composed of circular and strip metal particulate matter.