针对6061铝合金的电子束选区熔化(Selective Electron Beam Melting,SEBM)过程,采用ANSYS构建了温度场仿真三维有限元模型。考虑材料的热物性参数随温度的变化特性,通过高斯面热源在粉末床上移动,研究了电子束功率、扫描速度和铝合金预...针对6061铝合金的电子束选区熔化(Selective Electron Beam Melting,SEBM)过程,采用ANSYS构建了温度场仿真三维有限元模型。考虑材料的热物性参数随温度的变化特性,通过高斯面热源在粉末床上移动,研究了电子束功率、扫描速度和铝合金预热温度对熔池尺寸、熔池热历史的影响,为6061铝合金电子束选区增材制造工艺参数的选择提供理论依据。研究结果表明:熔池宽度、熔池深度随着电子束功率、预热温度的增大而增大;输入线能量小于0.19 J/mm时,熔池深度、宽度均随着扫描速度的增大而减小,熔池长度随扫描速度的增大而增大;当输入线能量大于0.19 J/mm时,熔池深度、宽度均随着扫描速度的增大而增大,但增大速率减小,熔池长度随扫描速度的增大而减小。电子束功率是影响熔池冷却速率的主要因素。不同扫描路径的粉末层温度分布不同,采用合理的扫描路径可使得整个零件的热分布更加均匀。展开更多
This article proposes a precise and ecofriendly micromachining technology for aerospace application called electrochemical machining in pure water （PW-ECM）. On the basis of the principles of water dissociation, a se...This article proposes a precise and ecofriendly micromachining technology for aerospace application called electrochemical machining in pure water （PW-ECM）. On the basis of the principles of water dissociation, a series of test setups and tests are devised and performed under different conditions. These tests explain the need for technological conditions realizing PW-ECM, and further explore the technological principles. The results from the tests demonstrate a successful removal of electrolytic slime by means of ultrasonic vibration of the workpiece. To ensure the stability and reliability of PW-ECM process, a new combined machining method of PW-ECM assisted with ultrasonic vibration （PW-ECM/USV） is devised. Trilateral and square cavities and holes as well as a group of English alphabets are worked out on a stainless steel plate. It is confirmed that PW-ECM will be probably an efficient new aviation precision machining method.展开更多
基金Aeronautical Science Foundation of China (02H52049)
文摘This article proposes a precise and ecofriendly micromachining technology for aerospace application called electrochemical machining in pure water （PW-ECM）. On the basis of the principles of water dissociation, a series of test setups and tests are devised and performed under different conditions. These tests explain the need for technological conditions realizing PW-ECM, and further explore the technological principles. The results from the tests demonstrate a successful removal of electrolytic slime by means of ultrasonic vibration of the workpiece. To ensure the stability and reliability of PW-ECM process, a new combined machining method of PW-ECM assisted with ultrasonic vibration （PW-ECM/USV） is devised. Trilateral and square cavities and holes as well as a group of English alphabets are worked out on a stainless steel plate. It is confirmed that PW-ECM will be probably an efficient new aviation precision machining method.
