Abstract: Dynamic mechanical properties of C72900 copper alloy and 15-5PH stainless steel at different strain rates were studied by Hopkinson pressure bar test. The strain-stress curve was fitted on the basis of Johnson-Cook constitutive equation to determine material parameters. The compression test was simulated by ABAQUS software to verify the accuracy of the constitutive equation. The results show that the flow stresses of C72900 copper alloy and 15-5PH stainless steel increased significantly with increasing strain rate by tests, and both the materials had the similar flow stress behavior. The simulated true stress-true strain curves of C72900 copper alloy and 15-5PH stainless steel in the plastic deformation stage were consistent with the test results, and the relative errors were less than 3%, indicating that the established Johnson-Cook constitutive equations could describe the flow stress characteristics of C72900 copper alloy and 15-5PH stainless steel well. The application of C72900 copper alloy instead of 15-5PH stainless steel on the gasket of C919 aircraft safety pin was feasible and reliable.