The metallurgical and mechanical properties of Ti6Al4V/(WC-Co) friction welds have ben investigated. The microstructure close to the bondline comprised a mixture of acicular and equiaxed α plus β phases. The diffusion of elements in the welded specimens has been detected. The fracture strengths of Ti6Al4V/(WC-Co) friction welds markedly improved when the cobalt content in the (WC-Co) carbide su...

The metallurgical and mechanical properties of Ti6Al4V/(WC-Co) friction welds have ben investigated. The microstructure close to the bondline comprised a mixture of acicular and equiaxed α plus β phases. The diffusion of elements in the welded specimens has been detected. The fracture strengths of Ti6Al4V/(WC-Co) friction welds markedly improved when the cobalt content in the (WC-Co) carbide su...

Frictional shear stress is usually determined by utilizing the coefficient of friction or the constant friction factor models. The present study deals with finite element analysis of double cup extrusion process to determine the relationship between constant friction factor (m) and coefficient of friction (µ), since the metal flow in this process is very sensitive to frictional conditions. Ther...

in this study, thermoplastic polyolefin elastomeric (tpo) nanocomposites were fabricated by friction stir processing. the effect of different pin geometries on clay dispersion and mechanical properties of the tpo nanocomposite reinforced with 3% wt nanoclay has been first investigated. the optimum pin geometry namely threaded cylindrical pin was then used to fabricate the nanocomposites contain...

the thermo-hydraulic behavior of the air flow over a two dimensional ribbed channel wasnumerically investigated in various rib-width ratio configurations (b/h=0.5-1.75) atdifferent reynolds numbers, ranging from 6000 to 18000. the capability of differentturbulence models, including standard k-ε, rng k-ε, standard k-ω, and sst k-ω, inpredicting the heat transfer rate was compared with the experi...

Using a combination of ellipsometry and friction force microscopy, we study the reversible swelling, collapse and variation in friction properties of covalently bound poly(N-isopropylacrylamide) (PNIPAM) layers on silicon with different grafting densities in response to exposure to good solvents and co-nonsolvent mixtures. Changes in the thickness and segment density distribution of grafted fil...

Vortex extrusion (VE) is a severe plastic deformation technique which is based on the synergies between high strain accumulation and high hydrostatic pressure. Such a high amount of pressure, places a mandate to seek the method for investigation of the load under processing conditions. For this, kinematically admissible velocity field and upper bound terms based on Bezier formulation are develo...

In high-pressure, high-temperature sliding contacts, WS2 nanoadditives react with the metal substrate to generate 100+ nm chemical tribofilms with a layered structure and excellent tribological properties. The friction, wear and micromechanical properties of WS2 tribofilms are compared with those of tribofilms formed by the zinc dialkyldithiophosphate (ZDDP) antiwear additive and ZDDP-organic f...

In this study, thermoplastic polyolefin elastomeric (TPO) nanocomposites were fabricated by friction stir processing. The effect of different pin geometries on clay dispersion and mechanical properties of the TPO nanocomposite reinforced with 3% wt nanoclay has been first investigated. The optimum pin geometry namely threaded cylindrical pin was then used to fabricate the nanocomposites contain...

there are limitations in experimental studies on sand-gravel mixtures due to the small size of testingspecimens. due to this problem, many researchers have worked on prediction of the shear strength of mixture by testingthe sandy fraction of soil alone and developed empirical relationships. most of the previous relationships have beendetermined for low surcharge pressures in which particle brea...