Design and deformation mechanism of CoCrNi medium entropy alloy with gradient heterostructure
CoCrNi is a typical medium entropy alloy with high plasticity but low tensile strength.The trade-off problem limits its engineering applications.In this work,the heterogeneous structure of the gradient grain and twin was introduced into a CrCoNi medium entropy alloy by rolling annealing and rotating accelerated shot peening.The result show that this design achieves an excellent strong plasticity with the yield strength,tensile strength and fracture plasticity of 665 MPa,950 MPa and 40.6％,respectively.During tensile deformation,the gradient heterostructure can produce the hetero deformation-induced hardening,improve the yield strength of the alloy,and maintain a high work hardening rate and an excellent ductility.Therefore,the introduction of the gradient heterostructure based on rolling,annealing,and rotating shot peening is an effective way to overcome the trade-off between strength and ductility.
CoCrNi medium entropy alloygradient heterostructurehetero-deformation induced hardenging
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维普
