Investigation of Decarburization Behaviour during the Sintering of Metal Injection Moulded 420 Stainless Steel

Metals

Hao He¹  Yimin Li¹  Jia Lou²  Muyao Liu²  Xinming Wang²  Xiaoping Ouyang²  Chuanfeng An³ 

[1] Research Centre for Materials Science and Engineering, Guangxi University of Science and Technology, Guangxi 545006, China;School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China;State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China;

关键词: metal injection moulding;    420 stainless steel;    decarburization behaviour;    densification;    sintering temperature;   

DOI  :  10.3390/met10020211

来源: DOAJ

【 摘 要 】

The decarburization behaviour during the sintering of metal-injection-moulded 420 stainless steel was investigated. Particular attention has been paid to the decarburization mechanisms and carbon distribution of parts sintered at different temperatures. The results indicate that the loss of carbon content occurs mainly through the reduction of surface oxides of powder particles or reaction with the atmosphere. Depending on the densification level, the sintering decarburization is separated into two stages. Below 1200 °C, decarburization occurs at the powder particle surface. The surface oxides react with the amorphous carbon or residual organics to pose the metal surface. At this time, the carbon content distribution of the sintered body is similar to that of the as-debound sample. The reduction of surface oxides promotes sintering. At 1200 °C, the densification speed is higher in the centre region of the sample, where the interconnected pores close and the second stage of decarburization takes place. At temperatures above 1200 °C, carbon atoms in the inner layers must migrate to the surface to react with the atmosphere. The decarburization speed is reduced and the carbon content distribution of the as-sintered part is similar to that of the dense decarburized part.

【 授权许可】

Unknown