Optimum Design of the Plasma Nitriding Technological Parameters of 1Cr18Ni9Ti Steel

The plasma nitriding technology of 1Cr18Ni9Ti steel was studied by an orthogonal test.The main factors which affect the nitride layer structure and properties were analyzed,and the optimized parameters were obtained.The treating layers of microstrutures are analyzed by optical microscope,and the room temperature microhardness measurement was performed on a microhardness tester.The results show that the main parameters of nitriding processing that affect the surface microstruture and properties are nitriding temperatures and N2∶H2.The maximum thickness of nitriding layer and microhardness are 56.50 μm and 1 732.00 Hv respectively.The optimum technical parameters are that temperature,time,pressure and the ratio of N2 to H2are 560 ℃,3 h,1,533.288 Pa and 1∶1,respectively.