Effect Of Shot Peening On Properties Of Fe-based Bulk Metallic Glass

Fe-based bulk amorphous alloys have very important research value due to their excellent mechanical properties,magnetic properties and lower cost,but their weak plasticity limits their wide application.Therefore,improving the room temperature ductility of Fe-based amorphous alloys is a key issue that needs to be solved urgently in the amorphous field.Shot peening is a surface treatment method that can effectively improve the room temperature plasticity of Zr-based amorphous alloys.However,for Fe-based amorphous systems,related research work is still rarely reported.Therefore,the development of shot peening of iron-based amorphous alloys is a scientific research work of very important research value and practical significance.In this paper,Fe₈₀P₁₃C₇ and Fe₇₄Si₃B₄P₁₀C₄Mo₅ amorphous alloys prepared by the J-quenching method are used.Different process parameters were used for shot peening,and the effects of shot peening parameters on the surface microstructure,the free volume,fracture morphology,mechanical properties and corrosion resistance of the amorphous alloy were studied.And the internal mechanism of shot peening to improve the room temperature plasticity of Fe-based amorphous alloys is deeply discussed.The main research work and conclusions are as follows:(1)The results show that shot peening can significantly improve the surface mechanical properties of Fe₈₀P₁₃C₇ and Fe₇₄Si₃B₄P₁₀C₄Mo₅ amorphous alloys.This is mainly due to the fact that shot peening introduces surface residual compressive stress,which promotes the proliferation of shear bands and hinders its expansion.In addition,shot peening can also induce and increase the free volume of amorphous alloys.These factors will improve the mechanical properties of amorphous alloys.(2)Shot peening parameters directly affect the shot peening effect.By optimizing shot peening strength and shot peening time,Fe-based amorphous materials with both high strength and good room temperature plasticity can be prepared.(1)For Fe₈₀P₁₃C₇ amorphous alloy,when the shot peening strength is 0.21 mm A,the room temperature compressive plasticity is increased by about 6 times,and the compressive strength is increased from 3330 Mpa to 3405 MPa,and the mechanical properties are the best;for Fe₇₄Si₃B₄P₁₀C₄Mo₅ amorphous alloy,when When the shot peening strength is 0.18 mm A,the compression strain is increased by about 4.7 times,and the compressive strength is increased from 3489 MPa to 3557 MPa,and the mechanical properties are the best.(2)When the shot peening strength is constant,appropriately prolonging the shot peening time can improve the mechanical properties of Fe based amorphous alloy.For Fe₈₀P₁₃C₇ amorphous alloy,shot peening at 0.18 mm A strength for 12 s,the plastic strain is increased by 5 times,and the compressive strength is increased to 3490 MPa;for Fe₇₄Si₃B₄P₁₀C₄Mo₅ amorphous sample,shot peening at 0.15 mm A strength for 16 s,the plastic strain of the alloy is increased by nearly 3 times,and the compressive strength is increased to 3712 MPa.(3)Shot peening also significantly promotes the improvement of the corrosion resistance of Fe-based bulk amorphous alloys.The electrochemical test results show that after shot peening,the self-corrosion potential of Fe₈₀P₁₃C₇ amorphous specimens increases,the self-corrosion current density decreases,the impedance becomes larger,the corrosion rate decreases significantly,and its corrosion resistance is enhanced.At a shot peening strength of 0.21 mm A,the Fe₈₀P₁₃C₇ amorphous sample has the best corrosion resistance when shot peened for 12 s.