Shape-forming and densification of ceramic superconductors

Aging effect in ceramic superconductors.

A three-dimensional lattice of the Josephson junctions with a finite self-conductance is employed to model ceramic superconductors. By using Monte Carlo simulations it is shown that the aging disappears in the strong screening limit. In the weak screening regime, aging is present even at low temperatures. For intermediate values of the self-inductance, aging occurs in an intermediate temperatur...

Ceramic-forming silicone compounds

Evaluation of Heterogeneous Densification, Anisotropic Shrinkage and Rheological Behavior of Ceramic Materials during Liquid Phase Sintering by Numerical-Experimental Procedure

The effective shear and bulk viscosity, as well as dynamic viscosity, describe the rheological properties of the ceramic body during the liquid phase sintering process. The rheological parameters depend on the physical and thermo-mechanical characteristics of the material such as relative density, temperature, grain size, diffusion coefficient, and activation energy. Thermal behavior of the cer...

Two point incremental forming of a complicated shape with negative and positive dies

In this work, incremental sheet forming of a complicated shape is investigated experimentally. Two point incremental forming with negative and positive dies are employed for manufacturing of a complicated shape with positive and negative truncated cones. The material is aluminum alloy 3105 with a thickness of 1 mm. The effects of process parameters such as sequence of positive and negative form...

On the Theory of the Ceramic Densification Process and of Recrystallization in Colloidal Solutions*

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...