Microstructure And Hot Deformation Behavior Of 301 Stainless Steel Containing Copper

301 is a typical austenitic stainless steel,which has been widely used in food production equipment,general chemical equipment,nuclear energy and other fields.In some steels,copper can significantly improve the corrosion resistance and antibacterial properties of the steels,and is beneficial to improve the strength and other properties of the steels.Therefore,a small amount of copper(0.443 wt%,1.090wt%,1.824 wt%)was added to 301 austenitic stainless steel in this paper,by using optical microscope(OM),scanning electron microscope(SEM),metallographic microhardness tester,thermal simulation test machine,high temperature confocal microscope and differential scanning calorimeter,the structural characteristics and thermal deformation behavior of copper-containing 301 were observed and analyzed comparing with a normal 301 steel.The experimental and analytical results show that copper is beneficial to refine the grains of 301 stainless steel,and the higher the copper content,the finer the austenite grains.The addition of copper delays the recovery and recrystallization of301 stainless steel during the hot rolling process,causing some grains to fail to recover and recrystallize,forming a thicker band structure.As the copper content increases,the number of thick bands increases.The amount of chromium carbides in the copper-containing 301 stainless steel has been significantly reduced.It is inferred that the addition of copper makes more chromium solid soluted in the matrix structure,and may also increase the solid solution amount of alloy elements such as carbon,and inhibits the formation of hard particles of carbon and chromium compounds,and the higher the copper content,the more obvious the impact.Copper is uniformly dispersed in hot-rolled 301 austenite.Copper has little effect on the hardness of the hot-rolled 301 stainless steel.Under different thermal deformation temperature and strain rate conditions,copper has little effect on the peak flow stress of 301 stainless steel during thermal deformation.Adding 0.443 wt%-1.824 wt%of copper can significantly increase austenite-grain coarsening temperature and???phase transition temperature.Adding 0.443wt%of copper can easily destroy the Cr₂O₃protective film during high-temperature oxidation,the ability to resist high temperature oxidation is weak.By addition 1.090 wt%and 1.824 wt%copper,the Cr₂O₃protective film is not easily destroyed during high temperature oxidation,and at the same time,it promotes the enrichment of chromium on the steel surface in the process of continuous high temperature oxidation,forming a dense protective film,which can significantly improve its resistance ability to high temperature oxidation.