Static Recrystallization of austenite after initial deformation of a Ni-30Fe alloy

The Static Recrystallization (SRX) phenomenon of austenite in C-Mn steels have a large impact on the final mechanical properties of the steel. However, the austenite recrystallization kinetics are difficult to investigate experimentally, due to solid-state phase transformations during cooling to room temperature. The best model alloys to examine...

An experimental and theoretical investigation of the effect of second-phase particles on grain growth during the annealing of hot-rolled AZ61 magnesium alloy

The mechanical properties of a magnesium alloy strongly depend on its grain structure. It is desirable to minimize grain growth during the post-forming annealing treatment, thereby minimizing the loss in strength while regaining ductility. In the present research, the annealing of the hot-rolled AZ61 Mg alloy at different temperatures for...

Modelling of Grain Boundary Segregation for Nanocrystalline Alloys: Applied to Pd-based Alloys

The Pd-based metal membranes have been focused on many studies, because they are the most promising candidates for hydrogen separation. If Pd-based membranes are designed in nanoscale, then the introduced high volume fraction of grain boundaries can act as fast diffusion paths for hydrogen atoms that leading to an increase of hydrogen separation...

Improvement of mechanical properties of AA6063 aluminum alloy after equal channel angular pressing by applying a two-stage solution treatment

A two-stage solution treatment composed of an initial soaking at 420 °C for 10 min and the second soaking at 500 °C for 10 min was applied to cold-worked AA6063 aluminum alloy samples after equal channel angular pressing (ECAP) for two and four passes. The microstructures and mechanical properties of the samples were compared with those of...

Numerical Modelling of Sintering of Alumina

In this project we introduce the sintering process, which involves two basic phenomena, pore shrinkage and grain growth, occurring simultaneously. The objective of this project is to quantitatively describe the sintering process incorporating the kinetics of pore shrinkage and grain growth. First we build a model for pore shrinkage separately....

Stress in sputter-deposited Cr films: Influence of Ar pressure

We studied the tensile stress and grain-width evolution in sputter-deposited Cr films with thickness from 20?nm to 2.7??m. Films were deposited in an industrial Hauzer 750 physical vapor deposition machine at 50–80?°C. The films exhibited a columnar microstructure. A power law behavior of the tensile stress as well as of the average grain width...

Stress in hard metal films

In the absence of thermal stress, tensile stress in hard metal films is caused by grain boundary shrinkage and compressive stress is caused by ion peening. It is shown that the two contributions are additive. Moreover tensile stress generated at the grain boundaries does not relax by ion bombardment. In polycrystalline hard metal films the grain...

Tensile stress in hard metal films

Thin films on substrates are usually in a stressed state. An important, but trivial, contribution to that stress stems from the difference in thermal expansion coefficient of substrate and film. Much more interesting are the intrinsic stresses, resulting from the growth and/or microstructure of the film. Intrinsic compressive stress was...