Experimental investigation of in-situ microstructural transformations in wire arc additively manufactured maraging 250-grade steel
Experimental investigation of in-situ microstructural transformations in wire arc additively manufactured maraging 250-grade steel
复制标题
电弧增材制造马氏体时效250级钢原位显微组织转变的实验研究
DOI：
10.1016/j.matchar.2022.112065
复制
发表时间：
2022
影响因子：
4.7
通讯作者：
Narra, Sneha P.
中科院分区：
文献类型：
--
作者：
Xu, Yao;Mishra, Brajendra;Narra, Sneha P.
由于高沉积速率和低原料成本等令人信服的因素，丝弧增材制造（WAAM）适用于大型部件的近净形制造。尽管有这些因素，但对于这种制造工艺的工业应用，理解工艺-结构-性能关系是必要的。然而，WAAM过程中的热循环和热积累会导致不同的显微组织转变。这些复杂性使得建立过程-结构-属性关系变得非常重要。因此，这项工作的目的是了解在制造材料的微观结构演变的各个方面。一套表征技术，包括光学显微镜，扫描电子显微镜，和电子背散射衍射被用来表征线弧增材制造的马氏体时效钢250薄壁。表征结果表明，晶粒细化和变化的沉淀类别和体积分数作为薄壁的高度的函数。然后，这些变化定性地与制造期间的热条件相关。总的来说，这项工作的结果揭示了热循环和热积累对制造马氏体时效钢250的微观结构演变的影响。
Wire arc additive manufacturing (WAAM) is suitable for near-net-shaped manufacturing of large-scale components due to compelling factors such as high deposition rates and low feedstock costs. These factors notwithstanding, an understanding of the process-structure-property relations is necessary for the industrial use of this manufacturing process. However, the thermal cycles and heat accumulation in the WAAM process can result in different microstructural transformations. These complexities make it non-trivial to establish the process-structure-property relations. Hence, the objective of this work is to understand the various aspects of microstructure evolution in an as-fabricated material. A suite of characterization techniques, including optical microscopy, scanning electron microscopy, and electron backscatter diffraction were utilized to characterize a wire arc additively manufactured maraging steel 250 thin wall. The characterization findings show grain refinement and variation in precipitation categories and volumetric fraction as a function of the height of the thin wall. These variations are then qualitatively related to the thermal conditions during fabrication. Overall, findings from this work shed light on the impact of thermal cycles and heat accumulation on the microstructure evolution in as-fabricated maraging steel 250.