中国激光, 2018, 45 (4): 0402003, 网络出版: 2018-04-13
电磁搅拌辅助Ni45合金的激光增材制造 下载: 879次
Laser Additive Manufacturing of Ni45 Alloys Assisted by Electromagnetic Stirring
激光技术 激光增材制造 电磁搅拌 数值模拟 组织 性能 laser technique laser additive manufacturing electromagnetic stirring numerical simulation microstructures properties
摘要
采用有限元和有限体积法,对交变磁场作用下激光增材制造Ni45合金过程进行了磁-热-流耦合数值分析。结合试验,探讨了外加磁场对凝固组织的演化规律和性能的影响。结果表明,外加磁场增强了由表面张力梯度和浮力耦合产生的强制性环流;随着磁场强度的增大, 激光熔池的对流传热逐渐增强,这使得激光熔池的温度梯度逐渐减小,凝固速率逐渐增大;受此影响,合金成形体的凝固组织逐渐细化,硬度和摩擦磨损性能提高。
Abstract
The magnetic-thermal-flow field coupling in the process of laser additive manufacturing of Ni45 alloys under alternative magnetic fields is numerically investigated by using the finite element and finite volume methods. The influence of the external magnetic field on the evolution trend and properties of solidification structures is investigated based on experiments. The results show that the introduction of external magnetic field enhances the compulsory convection resulted from the coupling between the surface tension gradient and the buoyant force. The convection heat transfer in the molten pool gradually enhances with the increase of magnetic field intensity, which makes the temperature gradient of the molten pool gradually decrease and the solidification rate gradually increase. As a result, the solidification structure of the alloy forming part is gradually refined, and the friction and wear performances are enhanced.
于群, 王存山. 电磁搅拌辅助Ni45合金的激光增材制造[J]. 中国激光, 2018, 45(4): 0402003. Yu Qun, Wang Cunshan. Laser Additive Manufacturing of Ni45 Alloys Assisted by Electromagnetic Stirring[J]. Chinese Journal of Lasers, 2018, 45(4): 0402003.