时效处理对NiW750高密度合金组织与性能的影响

A new high density alloy NiW750 is developed in this study, which is based on faced-center cubic structure and strengthened by a fine and dispersed phase. After aging at different temperatures, the quasi-static mechanical property of the alloy was tested, and the material characteristics under dynamic loading were investigated using the split Hopkinson pressure bar (SHPB) test. SEM and TEM were used to observe their microstructures, and the hardness of the microstructure was also tested. The results showed that in the range of 650~ 900 ℃, with the increase of aging temperature, the strength of the alloy increased at first, and then decreased obviously, while the change of toughness was the opposite. The alloy had the best performance after aging at 750 ℃. Under the condition of dynamic loading, the alloy showed obvious strain rate hardening effect, and adiabatic shear bands were formed within the sample. Furthermore, the collaborative deformation was observed between the deformation bands and the matrix. The hardness of the alloy was also higher after aging at 750 ℃, and the stress in the deformation zone was more concentrated, which led to the adiabatic shear fracture at the strain rate of 6 800 s^-1.