| The variation of material surface hardness has been investigated under different electricfields including 45~# steel and silicon slices, and the micro mechanim has also been explored.This article includes three parts. In the first part, the influence of electric field onmaterial mechanics capability was introduced, including electro—plastic effect, the influenceof electric field on solid phase transformation, the influence of electric field on materialsurface hardness and so on. Second, the theory and the research of material hardness and itscorrelative knowledge were summarized. Some representative works in domestic or overseasdomain were introduced emphatically. Finally, the work method and the research contentwere also showed.In the second part, the influence of quenching under electrostatic field on surfacehardness of 45~# steel was studied. According to the analysis of great deal of test datum, thequenching process of 45~# steel under electric field gives rise to a higher surface hardness thanthe traditional quenching. Increasing the intensity of the electric field can enhance the surfacehardness. According to metallographic observation, more and tinier martensiticmicrostructures were obtained after quenching under the electric field. The results using thetheory of solid phase transformation energetics and dynamics show that effect of electric fieldcan reduce the martensitic critical radius, r~*, the nucleation work,△G~*, and the nucleationrate I. More metallographic nuclei were obtained, as a result to decrease the speed ofmetallographic growing and to refine the crystal grain.In the last part, the influence of current field on surface hardness of silicon was studied.In the process of Rocker's indentation, imposing currents can decrease the surface hardness ofsilicon. This was a surface effect and didn't extend to the material matrix. The surfacehardness increases with the increase in the current and reaches a constant when the current ishigh enough.
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