A Novel Non-Equiatomic (W35Ta35Mo15Nb15)95Ni5 Refractory High Entropy Alloy with High Density Fabricated by Powder Metallurgical Process

A non-equiatomic refractory high entropy alloy (RHEA), (W35Ta35Mo15Nb15)95Ni5 with high density of 14.55 g/cm3 was fabricated by powder metallurgical process of mechanical alloying (MA) and spark plasma sintering (SPS). The mechanical alloying behavior of the metallic powders was studied systematically, and the microstructure and phase composition for both the powders and alloys were analyzed. Results show that the crystal consists of the primary solid solution and marginal oxide inclusion (Nb5.7Ni4Ta2.3O2). In addition, the maximum strength, yield strength and fracture strain are, 2562 MPa, 2128 MPa, 8.16%, respectively.

Composite Materials Based on Magnesium and Calcium Phosphate Compounds

This paper presents the process and results of the formation of multifunctional materials based on magnesium for the needs of implant surgery. An integrated approach has been developed, including: (i) the synthesis of porous magnesium preforms by means of a powder metallurgical process; (ii) formation of composites based on synthesized nanoscale hydroxyapatite powder and magnesium metal powder by spark plasma sintering technology.

Tensile Fracture of TiB Whisker Reinforced Ti Alloy Matrix Composites

TiB whisker reinforced Ti alloy matrix (Ti–TiB) composites have attracted attention as the aerospace materials with their high specific mechanical properties for long time. However, strengthening mechanism of Ti–TiB composites has not been revealed because of the agglomeration and incomplete precipitation of TiB whiskers in the Ti alloy matrix yet. In this study, we addressed to fabricate fully-dense TiB whisker reinforced Ti-6Al-4V alloy matrix (Ti6Al4V–TiB) composites via powder metallurgical process, which have the microstructure to discuss their tensile properties with the theories for composite materials. The Young’s modulus and ultimate tensile strength of Ti6Al4V–10 vol% TiB composite were 130 GPa and 1193 MPa, respectively. Note that the elongation of Ti6Al4V–10 vol% TiB composite was approximately 2.8 % although the elongations of Ti–TiB composite have been reported are few (; less than 1%) due to the agglomeration of TiB whiskers in Ti matrix.

The Influence of Mo Content on Phase Transformation in Ti-Mo Alloys

Titaniumβ-type alloys are a class of interesting biomaterials that can exhibit a unique combination of mechanical as well as physicochemical and biological properties. The aim of this study is to develop a titanium-molybdenum alloys (Ti-x at % Mo,x= 15 and 23). These materials were prepared by the combination of mechanical alloying and powder metallurgical process. The details of the processing method were presented. The samples were characterized by X-ray diffraction, scanning electron micros-copy, chemical composition determination as well as density and Vickers microhardness measurements. The corrosion behaviour in Ringer solution was investigated, too. The crystallization of the obtained material upon annealing led to the formation of a near singleβtype alloys. The molybdenum content in titanium and heat treatment parameters of a nearly amorphous phase allow to synthesize Ti(β)-type alloys. The present study has demonstrated that Ti23Mo alloy can be the next generation of biomaterial for bone tissue engineering.

Abrasive Wear on Heat-Treated Recycling Aluminium AA6061 of Various Reinforcement Materials through Powder Metallurgical Process

The present study is aimed at investigating wear resistance of the heat treated of recycled aluminium type AA6061 for various reinforced methods (heat treatment reinforced by graphite and silica) using pin on disc method. In the study, weight loss value of the recycled chip of AA6061 was observed. Eight specimens were taken for the wear test. The results showed that the wear resistance increased for specimens treated by heat treatment. This increase in wear resistance is value of micro hardness which increased with the increase of the percentage of silica reinforcement. Thus, the weight loss decreased and the volume loss also decreased.