Sintering of nickel-free high nitrogen 0Cr17MnllMo3N stainless steel prepared by powder injection molding

A kind of nickel-free high nitrogen austenitic stainless steel (0Cr17Mn11Mo3N) was prepared by powder injection molding. The effects of sintering parameters such as temperature, time and atmosphere on the relative density and nitrogen content were investigated. The results show that sintering temperature is the most important sintering parameter, with the increase of which the relative density of sintered specimens increases remarkably, whereas the nitrogen content decreases, and above 1 300 E the relative density of sintered specimens is over 99%. Sintering time has no obvious effect on the relative density and nitrogen content, and when the sintering temperature is high enough, the excellent densification of the powder can be achieved within 2 h. For the sintering of 0Cr17Mn11Mo3N stainless steel, sintering atmosphere has also a significant influence, and the higher relative density and lower nitrogen content can be obtained in N₂ + H₂ atmosphere than in high purity N₂ atmosphere. The optimal sintering conditions of 0Crl7MnllMo3N austenitic stainless steel are as follows:1 300℃, 2 h, and flowing high pure nitrogen. Under the optimal conditions, the relative density of sintered specimens can reach 99.1% and the mass fraction of nitrogen is as high as 0.78%.