Hot tearing characteristics of Mg–2Ca–xZn alloys

Two-Phase Modeling of Hot Tearing in Aluminum Alloys: Applications of a Semicoupled Method

Hot tearing formation in both a classical tensile test and during direct chill (DC) casting of aluminum alloys has been modeled using a semicoupled, two-phase approach. Following a thermal calculation, the deformation of the mushy solid is computed using a compressive rheological model that neglects the pressure of the intergranular liquid. The nonzero expansion/ compression of the solid and th...

Modeling of Stress, Distortion, and Hot Tearing

COMPUTATIONALMODELING of mechanical behavior during solidification is becoming more important. Thermal and microstructural simulations alone are insufficient to predict the quality of the final product that is desired by the casting industry. Accurate calculation of displacements, strains, and stresses during the casting process is needed to predict residual stress and distortion and defects su...

Modeling of Hot Tearing and Other Defects in Casting Processes

AS COMPUTATIONAL MODELS MATURE, their practical benefit to improving casting processes is growing. Accurate calculation of fluid velocities, temperature, microstructure, and stress evolution is just the first step. Achieving tangible improvements to casting processes requires the accurate prediction of actual casting defects and product properties. Defects that form during solidification are im...

Hot Plasticity of Alpha Beta Alloys

Hot Nanoindentation of Nanocrystalline Ni-W Alloys

High temperature nanoindentation experiments are conducted to assess the activation enthalpy for deformation of nanocrystalline Ni-W alloys, for grain sizes between 3 and 80 nm. Thermal softening becomes less pronounced at finer grain sizes, and the activation enthalpy has an apparent inflection at a grain size near ~10-20 nm, in the vicinity the Hall-Petch breakdown. This inflection is related...