ABSTRACT Three various 12CrNi2 alloy steels were successfully fabricated on 35CrMo alloy steel by laser melting deposition with the aim of investigating the effect of powder oxygen content on formability of 12CrNi2 alloy steel. The phase constituents, macroscopic morphology, microstructure, and microhardness of powders and samples were studied by some modern analysis methods. The experimental results showed that with the increase of the oxygen content from 220 to 600 ppm, the sphericity and density of the powders gradually decreased which led to the appearance of pores in the as-deposited samples. The phase constituent of three as-deposited samples with different oxygen contents was α-Fe(M) phase. The percentage porosity in the macroscopic morphology increased with the increase of the oxygen content. Meanwhile, the high oxygen content contributed to more pores and the crack formation in the microstructure. With the increase of oxygen content, the microhardness of the as-deposited samples would decrease.

中文翻译：

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粉末氧含量对激光熔化沉积12CrNi2合金钢成形性能的影响

摘要 为了研究粉末氧含量对 12CrNi2 合金钢成形性能的影响，采用激光熔化沉积在 35CrMo 合金钢上成功制备了三种不同的 12CrNi2 合金钢。通过一些现代分析方法研究了粉末和样品的相组成、宏观形貌、微观结构和显微硬度。实验结果表明，随着氧含量从 220 ppm 增加到 600 ppm，粉末的球形度和密度逐渐降低，导致沉积样品中出现孔隙。三个不同氧含量的沉积样品的相组成为α-Fe(M)相。宏观形貌中的孔隙率百分比随着氧含量的增加而增加。同时，高氧含量有助于在微观结构中形成更多的孔隙和裂纹。随着氧含量的增加，沉积态样品的显微硬度会降低。