Suggesting a full two level experimental factorial model with three factors to optimize Ti-HA biocomposite properties

A metal matrix composites (MMCs) is introduced to serve as synthetic bone grafts. The MMC was synthetized via powder metallurgical method after milling raw powder mixture of hydroxyapatite (HA) particles and pure titanium (Ti) powder. A full two level experimental factorial model with three factors (2^3) was developed to study the effect of three main parameters of synthetizing process on the hardness, density, and crystallite size of the composite. The synthetizing process parameters under consideration were the mechanical alloying time as well as the ceramic powder initial size and its mass fraction in the mixed powder. The results demonstrate that the composite’s hardness is increasing with higher HA mass fraction (W/W) of the composite and longer milling time. The analysis of data also show that the initial HA particle size has insignificant influence on the composite’s hardness, while higher HA content fraction in the MMC decreases the density of the composite

Dry Sliding Wear and Corrosion Performance of Mg-Sn-Ti Alloys Produced by Casting and Extrusion

The aim of the present study is to investigate the role of Ti on corrosion and the wear properties of Mg-5Sn-xTi (x = 0, 0.15, 0.75, 1.5 wt.%) alloys. The samples were fabricated by conventional casting followed by hot extrusion, and the studies were examined by means of a pin-on-disc tribometer at various loads of 6, 10, and 20 N with constant sliding velocities of 0.04 m/s at ambient temperature. The corrosion performance, using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS), was studied in a basic solution containing 3.5 wt.% NaCl. The observation indicated a drop in the wear rate with an increase in Ti, while the average coefficient of friction was raised in higher Ti contents compared to the base material. The sample with 0.15 wt.% Ti exhibited superior wear properties at 6 and 10 N of normal force, while the sample with 0.75 wt.% Ti presented better wear resistance for 20 N. Electrochemical test observations demonstrated that the Ti deteriorated the corrosion features of the Mg-5Sn alloy, owing to the galvanic effects of Ti. The Mg-5Sn alloy exhibited excellent corrosion behavior (corrosion potential (Ecorr) = −1.45V and current density (Icorr) = 43.92 A/cm2). The results indicated the significant role of Ti content in modulating wear and corrosion resistance of the Mg-5Sn alloy

Effect of Ti Content on Microstructure and Mechanical Properties of Mg-Sn Alloys Produced by Casting and Hot Extrusion

Magnesium (Mg) alloys have received significant attention in various fields of applications due to their low density, high specific strength, good machinability, and damping properties. In this study, Mg95-xSn5Tix (x = 0, 0.15, 0.75, 1.5 wt.%) alloys were produced through casting and hot extrusion; the effect of Ti content was investigated on microstructure and mechanical properties using microscopical analysis, x-ray diffraction, tensile, compaction, and Vickers hardness tests. The obtained results indicated that the presence of Ti leads to sensible grain refinement and a decrease in dendrite arm spacing (DAS). Ti content of 0.15 wt.% caused a fine and homogenous distribution of Mg2Sn phases. The results showed with an increase in Ti content up to 0.75 wt.%, the lotgering factor (LF) of (002) plane decreased, indicating reduced texturing. The sample with 0.75 wt.% showed the greatest ultimate tensile strength (296 ± 6 MPa), and the sample with 1.5 wt.% Ti resulted in the highest ultimate compression strength (479 ± 13 MPa)