摘要
激光选区熔化成型技术(SLM)在增材制造领域中有重要的价值。不同参数对其热过程的影响还需进一步研究。本研究在综合了成型过程中一系列复杂的物理化学现象的基础上,建立了SLM成型316L不锈钢的温度场数值模拟模型,研究了激光功率、扫描速率和扫描间距对SLM温度场以及熔池尺寸等的影响,并通过实验验证了模拟结果的可靠性。结果表明:激光功率和扫描间距对于温度场以及熔池尺寸的影响较大,而扫描速度对其影响相对较小;激光功率较小、扫描速率较大或扫描间距较大时,温度场内温度降低,熔池尺寸较小,易形成孔穴类缺陷;通过实验得到,上述条件下试样表面出现未熔融的球化粉末颗粒和孔洞,熔池稳定性降低,成型质量下降;相反条件下,熔池相对稳定,其表面质量改善,但出现少量飞溅物。实验结果与数值模拟结果基本一致,保证了数值模拟结果的准确性。
Selective laser melting(SLM) molding has important value in additive manufacturing. The influence of different technological parameters on the thermal process of SLM is still to be further studied. The study in a combination of a series of complicated physical and chemical phenomena in the process of forming, on the basis of establishing the SLM forming temperature field numerical simulation model of 316L stainless steel, laser power, scanning speed and scanning interval of SLM and molten pool size, the influence of the temperature field and the reliability of the results of numerical simulation was verified by experiment. The results show that the effect of laser power and scanning distance on the temperature field and the weld pool size is great, but the effect of scanning speed is relatively small. When the laser power is small, the scanning rate is large or the scanning spacing is large, the temperature in the temperature field decreases, the size of the molten pool is small, and hole defects are easy to form. Under the above conditions, the spheroidized powder particles and holes appear on the surface of the model surface, the stability of the molten pool decreases, and the forming quality decreases.On the contrary, the molten pool is relatively stable, and the surface quality greatly improves, but a small amount of spatter occurs. The experimental results are basically consistent with the numerical simulation results, which ensures the accuracy of the numerical simulation results.
作者
马海彬
马行驰
刘畅
吴懋亮
解瑞雯
MA Haibin;MA Xingchi;LIU Chang;WU Maoliang;XIE Ruiwen(Department of Energy and Mechanical Engineering,Shanghai University of Electric Power,Shanghai 200090,China)
出处
《热加工工艺》
北大核心
2022年第14期64-69,共6页
Hot Working Technology
基金
国家自然科学基金项目(51501108)。
关键词
激光选区熔化成型
数值模拟
温度场
熔池尺寸
selection laser melting molding
numerical simulation
temperature field
molten pool size
