光纤-半导体激光复合焊接技术充分结合了光纤与半导体激光热源的优势,在激光加工领域拥有巨大的潜力.针对2195铝锂合金开展光纤-半导体激光复合焊接试验,并定量研究激光功率对焊接形貌与气孔的影响.结果表明,光纤激光功率显著影响焊缝熔...光纤-半导体激光复合焊接技术充分结合了光纤与半导体激光热源的优势,在激光加工领域拥有巨大的潜力.针对2195铝锂合金开展光纤-半导体激光复合焊接试验,并定量研究激光功率对焊接形貌与气孔的影响.结果表明,光纤激光功率显著影响焊缝熔深,半导体激光功率显著影响焊缝上熔宽.基于回归分析方法建立焊缝横截面积预测模型.此外,光纤与半导体激光均对焊缝气孔缺陷的控制起着重要的作用,较高的光纤激光功率有利于降低气孔缺陷.对于4 mm厚2195铝锂合金,采用光纤激光功率为3.0 k W、半导体激光功率为2.5~3.0 k W时,熔池温度高且光纤-半导体激光复合作用范围大,焊接接头气孔缺陷少.展开更多
The principles of selective laser sintering (SLS) were applied in this experiment .The influence of laser power, scan distance, scan speed and other processing parameters of fiber laser on the pore properties, elastic...The principles of selective laser sintering (SLS) were applied in this experiment .The influence of laser power, scan distance, scan speed and other processing parameters of fiber laser on the pore properties, elastic modulus, and micro morphology, etc were investigated in this paper. Tests were conducted on 316L stainless steel powder. The results showed that porous metal material that meets the requirements of porous bionic human bone material (porosity of 33.4%-37.8%, average pore radius of 94.2-178 μm, elastic modulus of 7.43-12.76 GPa, nearly spherical regular pore) can be produced when sintered at 90-100 W laser power, with a scan speed of 21-23 mm/s and scan distance of 0.165 mm.展开更多
声波可以提高固体颗粒的流化质量是因声波振动破坏粒子间的作用力以及影响气体介质的流动特性。因此了解床内声场分布特性,对分析声波对气体介质的作用,从而应用声波技术改善流化质量具有重要意义。实验研究了声波频率、扬声器功率和布...声波可以提高固体颗粒的流化质量是因声波振动破坏粒子间的作用力以及影响气体介质的流动特性。因此了解床内声场分布特性,对分析声波对气体介质的作用,从而应用声波技术改善流化质量具有重要意义。实验研究了声波频率、扬声器功率和布风板开孔率等参数对无颗粒情况下床内声场的影响。实验研究表明,当声波频率低于截止频率时,床内声压级随频率增大而增大;声波频率高于截止频率时,床内声压级随频率增大而减小;且扬声器功率越大,床内声压级也增大,扬声器功率由75 W提高到125 W时,床内整体声压级可以增加10 d B以上;而布风板开孔率对床内驻波场的分布影响较小,且不影响声压级的整体大小。展开更多
文摘光纤-半导体激光复合焊接技术充分结合了光纤与半导体激光热源的优势,在激光加工领域拥有巨大的潜力.针对2195铝锂合金开展光纤-半导体激光复合焊接试验,并定量研究激光功率对焊接形貌与气孔的影响.结果表明,光纤激光功率显著影响焊缝熔深,半导体激光功率显著影响焊缝上熔宽.基于回归分析方法建立焊缝横截面积预测模型.此外,光纤与半导体激光均对焊缝气孔缺陷的控制起着重要的作用,较高的光纤激光功率有利于降低气孔缺陷.对于4 mm厚2195铝锂合金,采用光纤激光功率为3.0 k W、半导体激光功率为2.5~3.0 k W时,熔池温度高且光纤-半导体激光复合作用范围大,焊接接头气孔缺陷少.
基金National Nature Science Foundation of China (50972086)Science and Technology Project of Xianyang (2010K15-04)
文摘The principles of selective laser sintering (SLS) were applied in this experiment .The influence of laser power, scan distance, scan speed and other processing parameters of fiber laser on the pore properties, elastic modulus, and micro morphology, etc were investigated in this paper. Tests were conducted on 316L stainless steel powder. The results showed that porous metal material that meets the requirements of porous bionic human bone material (porosity of 33.4%-37.8%, average pore radius of 94.2-178 μm, elastic modulus of 7.43-12.76 GPa, nearly spherical regular pore) can be produced when sintered at 90-100 W laser power, with a scan speed of 21-23 mm/s and scan distance of 0.165 mm.
文摘声波可以提高固体颗粒的流化质量是因声波振动破坏粒子间的作用力以及影响气体介质的流动特性。因此了解床内声场分布特性,对分析声波对气体介质的作用,从而应用声波技术改善流化质量具有重要意义。实验研究了声波频率、扬声器功率和布风板开孔率等参数对无颗粒情况下床内声场的影响。实验研究表明,当声波频率低于截止频率时,床内声压级随频率增大而增大;声波频率高于截止频率时,床内声压级随频率增大而减小;且扬声器功率越大,床内声压级也增大,扬声器功率由75 W提高到125 W时,床内整体声压级可以增加10 d B以上;而布风板开孔率对床内驻波场的分布影响较小,且不影响声压级的整体大小。
