The study of nucleation mechanism of new grains during severe plastic deformation of magnesium alloys is of great importance to control the characteristics of final microstructures.  To investigate the role of discontinuous recrystallization, a wrought AZ31 magnesium alloy was deformed by accumulative back extrusion process at 330 °C.  The obtained microstructures were studied using optical and...

The effects of carbon content on the dynamic and static softening mechanisms of Ti microalloy steels were investigated both in ferrite and austenite regions. The results obtained showed that recrystallization rate decreased as the percentage of carbon content was increased from 0.0035 to 0.110. This is due to the Ti(CN) and TiC precipitates and also the free carbon content. In the ferrite reg...

An object is considered as “chiral” if it is not superimposable on its mirror image. Due to the presence of asymmetric carbon atoms, numerous molecules are chiral but other stereogenic centers provide the asymmetric character of molecular compound (e.g. sulfoxides). Metalorganic complexes can also be asymmetric even if the ligands do not have any stereogenic center. The equimolar mixture of two...

The fundamental processes of tribology related to friction, wear, and adhesion [1–3] are still not well understood [4,5]. When a single asperity touches and slides on a surface, complex phenomena such as local rearrangements of atoms, permanent change of the surface structure [6], and more macroscopic phenomena such as dislocation motion or microstructural changes can occur. As the interface is...

In the theory of the ceramic densification process the starting point is that the material transport consists mainly of diffusion processes. At least three different contributions are however distingutshable : volume diffusion, grain boundary diffusion and surface difksionl. For volume diffusion it has been shown tbeorctica& that in ionic compounds an optimal delusion rate can bc obtained by ap...

Strain induced precipitation in HSLA-100 steel was investigated by conducting hotcompression and relaxation tests at temperature range of 850°C to 1100°C and strain rate of 0.001s-1 to 1s-1. The absence of dynamic recrystallization at temperatures below 1000°C was attributedto the influence of dynamic precipitation. The stress relaxation tests showed that strain inducedprecipitation is possible...