Dynamic Mechanical Properties of AerMet100 Ultra-high Strength Steel

The AerMet100ultra-high steel was cryogenic treated after quenched and then was tempered under different temperatures,the OM,SEM and TEM techniques were used to observe the microstructure after heat treatment.The effect of different heat treatments on the dynamic mechanical properties was investigated using the split Hopkinson pressure bar.The results indicate that the content of residual austenite is reduced,the dynamic plasticity is enhanced and the comprehensive properties are improved after cryogenic treatment.Under high strain rate(1000-4200s~(-1)),compared with the quasi static,material shows strain rate hardening effect obviously.The dynamic compression strength increases initially and then decreases with increasing tempering temperature,the peak value of about 2800 MPa appears when the tempering temperature is 482℃.The material fracture form is the shear fracture when the steel is under the dynamic loading.