| 24Mn-13Cr-0．44N,24Mn-18Cr-3Ni-0．62N,1Cr18Ni9Ti-three kinds of austenitic stainless steels-were studied in this paper. Tensile properties of a new type austenitic stainless steel 24Mn-18Cr-3Ni-0．62N at room temperature were investigated. During tensile the austenitic stainless steel has not obvious yield point elongation. Tensile property parameters are:σ=525MPa,σ=890MPa,δ=41%, (?)=57%, n=0．421．It possesses very high strength and excellent plasticity. Slip bands formed were coarse and dense, regular triangle deformation microstructure can be founded if optical microscopy section is parallel or approximately parallel to (111) plane.The fracture is toughness fracture . The inclusions are one of crack headstream, and purifying materials can further enhance tensile strength of materials.At the same time, abrasive wear properties of high nitrogen austenitic stainless steel under different loads were investigated in this paper, and compared with that of 18-8 austenitic stainless steel .The mechanism of abrasive wear was discussed. Under the three low loads , wear loss of 18-8 stainless steels is sharply increased with increasing of loads, but the influence of load on two kinds of high nitrogen austenitic stainless steel is smaller. Besides, shape and size of abrasive particles have an important effect on resistance to wear of materials. Under the same load, wear loss of coarse sands is more than that of fine sands. The earier stage of wear is mainly abrasive wear, and the most obvious feature is furrow. The advanced stage of wear is mainly adhesive wear. Then main wear mechanism is adhesion and flake, and there are part ploughing trace and a small quality of microcrack. With increasing of loads, abrasive wear is aggravating , adhesive wear advances and appears interaction between abrasive wear and adhesive wear. During wear, 18-8 austenitic stainless steel causeεmartensite transformation in the subsurface stratum, while two kinds of nitrogen-containing austenitic stainless steel few or almost not causeεmartensite transformation, instead appears large numbers of dislocations and deformation twins. The microhardness of wear profile was tested, it is found that hardness of common austenitic stainless steel increases obviously, but that of new type austenitic stainless steel increases less evidently. That is to say, work-hardening of nitrogen-containing austenitic stainless steel is not enough. One possible conclusion is : Just as high manganese steel, wear-resistance of the new type austenitic stainless steel performances more obviously under high loads.Furthermore, resistance to pitting corrosion properties of three kinds of austenitic stainless steel was studied. The results show that resistance to pitting corrosion of two kinds of nitrogen-containing austenitic stainless steel are better than that of 18-8 austenitic stainless steel. The number of nitrogen-containing austenitic stainless steel is less than that of 18-8 austenitic stainless steel at room temperature and high temperature. It is founded that pitting corrosion pattern of high nitrogen austenitic stainless steel 24Mn-13Cr-0．44N possesses regular triangle structure At high temperature of 50 degree centigrade, which is austenitic (111) plane. It is showed that nitrogen-containing austenitic stainless steel possibly happen pitting corrosion firstly in austenitic slip plane (111) when the temperature rises. The content of manganese of the new type austenitic stainless steel is very high and the inclusions are much more, so purifying materials can further enhance resistance to pitting corrosion properties of the new type austenitic stainless steels.
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