Nitriding of Fe-18Cr-8Mn stainless steel powders by mechanical alloying method with dual nitrogen source

作者：Duan, Cuiyuan; Chen, Cheng; Zhang, Jiaping; Shen, Yifu^*; Feng, Xiaomei

来源：Powder Technology, 2016, 294: 330-337.

DOI：10.1016/j.powtec.2016.02.048

• Nitriding
• Stainless steel
• Dual nitrogen source
• Mechanical alloying

In the present work, mechanical alloying (MA) method was applied to nitride Fe-18Cr-8Mn stainless steel powders through simultaneous dissociation of chromium nitrides and nitrogen molecules at room temperature. The formation of nitriding originated in the combined effects of the introduction of mechanical energy, plastic deformation, and refinement of particle and grain. The nitrogen content reached to 3.69% after milling for 30 h. The microstructure features of powder particles were affected by the milling time. The phase transformation of alpha-Fe to gamma-Fe phase occurred after milling for 15 h, which was resulted from the function of nitrogen solution and the MA process. The crystalline size decreased, while the internal strain increased by increasing the milling time. The sintering process performed in nitrogen atmosphere could prevent massive nitrogen loss. The samples with powder milled for 30 h developed a fully austenite structure after sintering and subsequent water quenching, which had 3.51% of nitrogen content, 92% of relative density and the microhardness reached to 549 HV0.1.

• 出版日期2016-6
• 单位南京航空航天大学