激光增材制造成型马氏体时效钢研究进展

本文较全面地综述了国内外激光增材制造成型马氏体时效钢(MS)的研究和应用现状。分析了选区激光熔化(SLM)制备MS特有的优势,并从SLM成型MS参数与性能优化、成型各向异性、时效强化机理、梯度材料和模具应用5个方面进行了系统介绍。研究表明,SLM成型MS的工艺窗口较宽,易获得成型致密度>99%的试样;经过激光和热处理工艺参数优化后,其力学性能可达标准锻件水平。MS时效强化遵循Orowan位错绕过机制,成型方向对MS力学性能影响较小。此外,SLM能够制备高结合强度MS基梯度材料(MS-Cu和MS-H13等)零件,为制备梯度材料功能件开辟了新途径。最后,介绍了SLM成型MS面向随形冷却模具的应用,并提出了今后的研究展望。

Research Progress of Laser Additive Manufacturing of Maraging Steels

Additive manufacture is recognized as a world-altering technology which triggered a world-wide intensive research interest. Here the research progress and application of the laser additive manufacturing maraging steel(MS) are systematically outlined. The advantages of selective laser melting(SLM) additive manufacture of MS is emphasized. The processing parameter and properties optimizations, build orientation based anisotropies, age hardening mechanism, gradient materials, and applications in die and moulds of SLM-processed MS are reviewed in detail. Achieving relative density of >99%in SLM-processed MS is effortless, owing to the wide SLM process window of MS. Mechanical properties of MS produced with optimized SLM processing parameters and post heat treatments are comparable to traditionally wrought parts. The build orientation hardly affects the property anisotropies of MS. The age hardening behaviour in MS follows Orowan bowing mechanism. MS-based gradient multi-materials(such as MS-Cu, MS-H13, etc.) with high bonding strength are fabricated by SLM, which provides a new approach to produce high-performance functionally gradient multi-materials components. Lastly, the application in conformal cooling moulds of SLM-processed MS is elucidated, and future research interests related to MS are also proposed.