Hot Stamping High Tensile Steel High Temperature Anti-oxidation Experimental

With the rapid development of China’s automobile industry and the requirementof energy saving and environment, the automotive lightweight technology has beenwidely used in the field of automobile. The hot stamping high strengthsteel structure can reduce the mass of the components, it makes lightweight cometrue and even improve the strength of materials. But in the process of heating, steelwill react with oxidizing gas then generate a thick oxide layer. On the one hand, itleads to a waste of resources, but also impact on the material properties, On the otherhand, the existence of the oxide layer will increase the machining process,and it willreduces the lifetime of mould. In this case, it is very important to study the oxidationand anti-oxidation regularity.In this paper, through the research on the regularity of oxidation kinetics of fourkinds of high strength steel in the atmosphere, master the regularity of oxidationmaterial. Optimize the processing parameters by using the method of orthogonalexperiment and response surface optimization, then we get the best conditions ofheating temperature is850℃~900℃, holding time was3.09min to4.29min,quenching temperature is650℃~680℃. Under these conditions, the oxidationability of the material surface is lower, and can satistfy the performance requirementsof the hot stamping technology.In order to study deeply in the anti-oxidation, we take it from the atmosphere andoxidation protection coating research. Building a purity of99.9%nitrogenatmosphere through modification of the heating furnace which can reduce theoxidation effectively. Combined with our previous studies of oxidation, we preparedhigh-temperature oxidation coating with aluminum, silica, aluminum oxide, carbon,binder-based. Coatings that were prepared in the range of900℃, can be more evenly spread over the substrate surface and form a coating layer having oxidation effect. Itcan significantly reduce the oxidation loss material surface.By hardness measurement, observation of microstructure, XRD analysis, SEMobservation interface, We found that the anti-oxidation measures does not causeexcessive damage. At the same time, the material hardness value is4~5times higherthan the original. Organization transformation uniform, a uniform distribution of lathmartensites, oxidation weightless and oxidation degree of thinning reduced at thesame time, all above show that multiple anti-oxidation measures are effective.