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The effect of single and duplex stage heat treatment on the microstructure and mechanical properties of cast Ti-6Al-4V alloy was studied. The single stage heat treatment (SSHT) involved solution annealing at 935°C for 10 min followed by water quenching, while the duplex stage heat treatment (DSHT) involved solution annealing at 935°C for 10 min, furnace cooling to 600 and 700°C, followed by isothermal holding for 30 min and subsequent water quenching. The properties characterization was conducted using microstructure investigation along with tensile, hardness, and Charpy impact tests. The impact fracture surfaces were observed using Scanning Electron Microscope. After SSHT, an increase in the tensile strength and hardness at the expense of the tensile elongation and impact toughness was recorded as compared with the as-cast alloy. This is attributed to the formation of a brittle a 0 martensite phase in the microstructure after quenching from 935°C. On the other hand, DSHT enhances the percent elongation and impact toughness over the as-cast alloy and SSHT. The formation of a 0 martensite-free microstructure as well as controlling the composition of the different microstructural constituents during DSHT optimizes the mechanical properties.

The gravity die casting method was used to produce functional Cu–Cr–Zr alloys with various compositions. The functional electrical, mechanical, and wear properties of Cu–Cr–Zr alloys were studied at different aging times at 500°C. The optimum aging time that results in the best combination of hardness and functional electrical properties changes with the chemical composition of the alloys; the alloys with higher Zr content require a longer time to attain peak hardness. Complicated wear mechanisms are active in the Cu–Cr–Zr alloys. The alloys with the highest Zr and Cr contents exhibit the highest hardness and tensile strength with low wear resistance. The best Cr content is found to be just below the solubility limit at the solutionizing temperature.

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The present work studied the effect of filling epoxy matrix by different types and concentrations of nanoparticles on the friction and wear behaviors. Various concentrations (0.2 %, 0.4 %, 0.6 %, 0.8 % and 1 wt.%) of multi walled carbon nano tubes (MWCNTs), aluminum oxide (Al2O3), and silica (SiO2) nanoparticles were used to reinforce epoxy matrix. These epoxy nanocomposites are widely used as indoor flooring tiles in schools, boutiques, hospitals, offices, conference rooms, homes, trade fair stands and homes for the aged. Experiments involved sliding of the epoxy nanocomposite specimens against rotating steel disc at dry sliding condition. Experiments were carried out using a test rig of pinon-disc, designed and manufactured for the test. The friction force was measured using load cell which connected with a digital screen to detect the friction force. All experiments were done at room temperature and carried out at constant normal load (7 N), constant speed (0.93 m/sec) and constant running time (300 seconds). The worn surfaces were investigated with back scattered scanning electron microscopy (SEM). Based on the observations in the present work, it was found that addition of the tested filling nanoparticles have greatly affected the friction and highly improves wear resistance.