Fracture behavior of Ni-W alloy probed by in situ synchrotron X-ray diffraction

Abstract In situ synchrotron X-ray diffraction experiments were conducted to extract strain distributions in Ni-30W (wt%) alloy processed by Spark Plasma Sintering and loaded in tension. The alloy was designed for a strength-ductility tradeoff. It has a microstructure made of multi-crystalline W clusters embedded in Ni(W) solid solution matrix. Lattice strain analysis made it possible to separate the respective behavior of the two phases. Indeed, stress (590 MPa) and strain thresholds (2%) at which cracks initiate and propagate inside the W were detected. Further hardening observed between 2% and 10% is attributable to the Ni(W) solid solution.