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Elshalakany, AB.; Ali, S.; A. Amigó Mata; Eessaa, AK.; Mohan, P.; Osman, T.; Amigó, V. (2017). Microstructure and Mechanical Properties of Ti-Mo-Zr-Cr Biomedical Alloys by Powder Metallurgy. ABSTRACTTitanium and its alloys have been widely used as biometals due to their excellent biocompatibility, corrosion resistance and moderate mechanical properties. Ti-15Mo-6Zr based alloys and a series of Ti-15Mo-6Zr-xCr (x = 1, 2, 3, 4 wt. %) alloys were designed and fabricated by powder metallurgy for the first time to develop novel biomedical materials. The microstructure, internal porosity and mechanical properties of the sintered Ti-15Mo-6Zr and Ti-15Mo-6Zr-xCr alloys were investigated using scanning electronic microscopy (SEM) and bending and compression tests. The experimental results indicated that the microstructure and mechanical properties of these alloys changed as different Cr levels were added. The addition of small Cr levels further increased the β-phase stability, improving the properties of the Ti-15Mo-6Zr-xCr alloy. However, all of the alloys had good ductility, and the Ti-15Mo-6Zr-2Cr alloy had lower bending and compression moduli (31 and 23 GPa, respectively) than the Ti-15Mo-6Zr-based alloys (40 and 36 GPa, respectively). Moreover, the Ti-15Mo-6Zr-2Cr alloys exhibited higher bending and compression strength/modulus ratios, which were as large as 48.4 and 52.2, respectively; these were higher than those of the Ti-15Mo-6Zr-based alloy (41.3 and 33.6, respectively). In the search for a better implant material, β phase Ti-15Mo-6Zr-2Cr, with its low modulus, ductile properties, and reasonably high strength, is a promising candidate.

The major objective of this study was to examine the viability of using 5, 10, or 15 mass% of Activated Alum Sludge waste (AAS) instead of Ordinary Portland Cement (OPC) as a pozzolanic ingredient in concrete. This fundamental inquiry framed the investigation and OPC-AAS-hardened composites were studied to see whether they may benefit from inexpensive nanocomposites in terms of improved physical properties, mechanical strength, and resistance to heat and flame. The investigation set out to see how inexpensive nanocomposite might be put to use and the nanoparticles of CuFe2O4 spinel with an average size of less than 50 nm were successfully manufactured. Many different OPC-AAS-hardened composites benefit from the addition of CuFe2O4 spinel, which increases the composites' resistance to fire and enhances their physicomechanical properties at roughly average curing ages. Synthesized CuFe2O4 spinel was shown to have desirable characteristics by TGA/DTG and XRD. By using these methods, we were able to identify a broad variety of hydration yields, including C–S–Hs, C–A–S–Hs, C–F–S–Hs, and Cu–S–Hs, that enhance the physicomechanical properties and thermal resistivity of OPC-AAS-hardened composites as a whole. The composite material comprising 90% OPC, 10% AAS waste, and 2% CuFe2O4 has several positive economic and environmental outcomes.

T he corrosion behavior of uncoated and Ni, Cu and Cd coated steel alloy 4130 in 3.5 wt. % NaCl solution was anticipated. The Ni-coated sample showed greater corrosion inhibition effect than both Cu-coated and Cd-coated depending on the obtained results of open circuit potential, polarization curves, impedance spectroscopy and cyclic voltammetry. The surfaces of uncoated and coated samples are characterized by scanning electron microscopy before and after immersion in salt solution. The best corrosion resistance and surface morphology achieved in Ni-coated steel alloy. The inhibition efficiencies of tested samples were 90.7, 89.1 and 56.9 for the Ni-coated, Cu-coated and Cd-coated respectively.