Influence of Replacing Molybdenum with Tungsten on the Creep Fracture Property of Waspaloy Nickel-Based Alloy

Alloys meeting the requirements of “700 °C and above” advanced ultra-super-critical technology, with higher thermal efficiency, have been developed in recent years. Here, a new wrought Ni-based superalloy excellent high-temperature creep strength based on Waspaloy has is proposed as candidate material for application 700 class steam turbine blades. In this alloy, Molybdenum (Mo) partially replaced by Tungsten (W). Creep tests shown that alloy 70 MPa creep-rupture than at extrapolating experimental data. Detailed mechanisms analyzed means scanning electron microscopy, transmission chemical phase analysis view to devising potential approaches performance improvements. The results showed partial replacement Mo W had negligible effect composition carbides precipitated alloy. Instead, amount ?? was significantly increased, mismatch between ? phases reduced. way, stability its coarsening rate reduced, critical shear stress increased. As result, creep-fracture