Spallation damage of 90W-Ni-Fe alloy under laser-induced plasma shock wave

Laser shock loading is a more promising technology for investigating spallation damage in materials under shock-wave loading. In this paper, shock-induced spallation in a 90W-Ni-Fe alloy at an ultrahigh tensile strain rate of 10(6) s-(1) is investigated using a superintense ultrafast laser facility. The spallation of the 90W-Ni-Fe alloy was dominated by a trans granular fracture of tungsten(W) particles with a high spall strength of 6.46 GPa. Here, we found an interesting phenomenon that the formation of nanograins inside W particles leads to a new mode of transcrystalline fracture of W particles during the laser shock loading. Futhermore, most voids were nucleated inside the W particles rather than at the W/g-(Ni, Fe) matrix-phase interface. This result contradicts the fracture theory under quasi-static loading, which posits that the W/g-(Ni, Fe) matrix-phase interface is not the preferred site for the initial failure under shock loading. (c) 2022 The Authors. Published by Elsevier B.V.

Automated summary

This paper investigates shock-induced spallation in a 90W-Ni-Fe alloy at an ultrahigh tensile strain rate using a superintense ultrafast laser facility. The study reveals a new mode of transcrystalline fracture of tungsten particles due to the formation of nanograins inside the particles during laser shock loading. The results also show that most voids are nucleated inside the tungsten particles rather than at the W/g-(Ni, Fe) matrix-phase interface, contradicting the fracture theory under quasi-static loading.