激光立体成形Fe-30Mn-9.5Al-2C钢的工艺与组织特征

Technology and microstructure characteristics of Fe-30Mn-9.5Al-2C steel by laser solid forming

Fe-Mn-Al-C系列轻质钢具有低密度和良好的力学性能,契合航空航天、汽车能源和深海探测等领域对轻质高强材料的需求。然而,Al作为其轻量化和性能调控主要元素,大量添加会导致传统浇铸困难,限制了其在复杂异形构件上的应用。本研究利用激光立体成形增材制造技术成形自由度高、微熔池冶金的特点解决上述问题。以Fe-30Mn-9.5Al-2C为研究对象,通过正交试验探寻最优工艺参数,研究最优工艺参数下的物相组成和组织演变。结果表明,最优的工艺参数下组织由奥氏体、少量铁素体和κ-碳化物构成,硬度最高可达539HV。研究结果可为激光立体成形Fe-Mn-Al-C钢提供指导。

Fe-Mn-Al-C lightweight steels exhibit low density and good mechanical property,making them suitable for lightweight and high strength material needed in aerospace,automotive energy,and deep-sea exploration.Nevertheless,as a crucial element for its weight reduction and performance control,the large addition of Al will lead to the difficulty of traditional casting,which limits its application in complex-shaped components.Therefore,laser solid forming additive manufacturing technology was used to tackle the aforementioned problems by exploiting its high forming freedom and micro-molten pool metallurgical properties.Taking Fe-30Mn-9.5Al-2C as the research object,the optimal combination of process parameters was explored by orthogonal test,and the phase composition and microstructure evolution under the optimal process parameters were studied.The results show that under the optimal process parameters,the microstructure is composed of austenite,a small amount of ferrite andκ-carbide,and the hardness is up to 539HV.The research results can guide the manufacturing of Fe-Mn-Al-C steel via laser solid forming.