期刊论文

Effect of Rosin and Starch Additives on the Microstructure and Mechanical Properties of Fe-based Alloy Powder Laser Forming Sample

中文

材料导报

1005-023X

2019

33

11

1848-1852

10.11896/cldb.18010137

国家自然科学基金(51474130) 湖南省高校重点试验室(湘财教指[2014]85号).

本校为第一机构

利用5 kW 横流CO_2激光器在基材上分别成形未包覆和包覆松香、淀粉双层微膜的铁基合金粉末试样,并通过试验研究它们的元素含量、显微组织和力学性能。研究表明,松香、淀粉双层微膜在激光熔池中气化燃烧形成暂态还原性保护气氛,使成形粉末的氧化烧损减少。双层微膜包覆粉末试样中Cr、Ni、Si 含量比未包覆粉末试样平均增加0.12%,C、B 含量比未包覆粉末试样平均增加0.015%。相较于未包覆粉末试样,双层微膜包覆粉末试样气孔、夹渣等缺陷较少,成形试样的质量更好。松香、淀粉双层微膜包覆粉末试样的平均洛氏硬度、平均抗拉强度分别为56.12HRC、1847 MPa,比未包覆粉末试样提高了4.7%、16.2%。

There were two types of specimens formed on steel substrate in experiment by using a 5 kW cross-flow CO2 laser. One was the net iron-based alloy powder sample, while the other was a sample of the rosin and starch double-layer micro-membrane coated iron-based alloy powder. The composite, microstructure and mechanical properties of those two types of test specimens were then investigated experimentally. It suggested that the rosin and starch double-layered micro-membrane was gasified and burnt in the laser weld pool. Along with that transient reductive atmosphere formed. This atmosphere then pro...