An interesting change of scale sequence occurred during oxidation of nanocrystalline surface layer by means of a surface mechanical attrition treatment. The three-layer oxide structure from the surface towards the matrix is Fe3O4, spinel FeCr2O4 and corundum (Fe,Cr)2O3, which is different from the typical two-layer scale consisted of an Fe3O4 outer layer and an FeCr2O4 inner layer in convention...

dissimilar metals friction welding of austenitic–martensitic stainless steels is commonly used in order to manufacture engine valves in the automobile industry. in this study, x53crmnnin219 (austenitic stainless steel) and x45crsi93 (martensitic stainless steel) valve steel rods were welded by friction welding process. the welded joint was then heat treated at 760 0c for 60 min. mechanical prop...

Abstract: In this research, the oxidation behaviour of high Aluminum heat resistant steel (%25Cr,%20Ni,%8Al) hasbeen evaluated at the temperature range of (1000-1300ºC).The results showed that there was no countinous healinglayer on the surface of the alloy when Al increased up to %5.5 and the oxidation resistance of steel decreased due toformation of spinel oxides on the surface.By increasing ...

aisi 4340 steel is one of the super strong steels that can be selected for different applications. by designing theproper cycles of heat treatment, the optimum microstructure and properties of this steel can be achieved. in thisstudy, different heat treatment cycles were introduced to achieve the optimum microstructure and improve themechanical and magnetic properties of aisi 4340 steel. the re...