Zinc coating is formed by the heterogeneous assembly of the Γ, Γ1, δ, ζ and η phases whose mechanical properties greatly differ from each other. Thermal strains resulting from large differences between thermal expansion coefficients are partially relaxed by the formation of a crack network. In order to model this phenomenon, initial hardness, thermal expansion coefficient αi and toughness (KIC)...

in this research, a novel method to decrease micro-residual stresses of fibrous composites by adding carbon nanotubes (cnts) is proposed in detail. the negative coefficient of thermal expansion and the high young’s modulus of cnts can be utilized to counterbalance the process induced residual stresses in composites. to this end, first, the effects of adding cnts to the matrix of fibrous composi...

Thermal expansion involves a response of a material to an external stimulus that typically involves an increase in a crystallographic axis (positive thermal expansion (PTE)), although shrinking with applied heat (negative thermal expansion (NTE)) is known in rarer cases. Here, we demonstrate a means to achieve dynamic molecular motion and thermal expansions in organic solids via co-crystallizat...

Zr2WP2O12/ZrO2 composites were fabricated by solid state reaction with the goal of tailoring the thermal expansion coefficient. XRD, SEM and TMA were used to investigate the composition, microstructure, and thermal expansion behavior of Zr2WP2O12/ZrO2 composites with different mass ratio. Relative densities of all the resulting Zr2WP2O12/ZrO2 samples were also tested by Archimedes' methods. The...

The purpose of this study is to investigate the influence of setting expansion and thermal expansion of the phosphate-bonded investment on the fitness of cast claspsfabricated by a superelastic Ni-Ti alloy. Investment models were made from the columnar stainless-steel model supposed the abutment tooth the various dilusion colloidal silica solutions.Cast clasps were fabricated using by using a s...

Leucite is a major crystalline component of dental porcelains. The presence of tetragonal leucite in dental porcelains increases their coefficients of thermal expansion due to its high coefficient of thermal expansion (20-25 x 10(-6)/degrees C). This is particularly useful for those porcelains designed for bonding to precious metals and nickel alloys. The purpose of this study was to determine ...