In this study, the production of full-density Cu-10Sn bronze parts by selective laser melting (SLM) technique and the examination of microstructural, mechanical and corrosion properties were carried out. Cu-10Sn pre-alloyed powders produced by gas atomization technique were shaped using SLM technique within selected parameters and then microstructural properties were determined. Depending on the microstructural properties, the mechanical and corrosion behaviors were determined. The obtained results were compared with similar bronze materials produced by conventional methods. Different characterization techniques were used for microstructural characterization. The microstructure of the Cu-10Sn alloy was observed to consist of dendritic primary α and δ-Cu41Sn11 phases. According to the mechanical test results of the samples produced at densities of 8.75 g cm-3 at room temperature, the yield strength was measured as 420 MPa, the tensile strength was 578 MPa, the elongation was 32 % and the hardness value was 160.3 HV0.2. For the electrochemical experiments, the corrosion rate of the samples was found to be 4.38 mpy. As a result of the productions and experiments, it was determined that the samples produced by the SLM method provide very good mechanical and corrosion properties compared to the literature.

Abstract-This study aims to compare the effect of Al 2 O 3 nano-particle additions on the densification, mechanical and electrochemical properties of Titanium (Ti) matrix composites. The Ti and Al 2 O 3 nano-particles were dry mixed and molded using by traditional Powder Metallurgy (PM) techniques. After the molded process, the samples were sintered at 1200º C and 1300º C for 60 min. under high level vacuum. Mechanical property, microstructural characterization and electrochemical property of the sintered samples were performed using tensile testing, hardness, optical, scanning electron microscopy and electrochemical corrosion experiments. All the powders, fracture surfaces of sintered samples were examined using scanning electron microscope. The sintered density of straight as well as Al 2 O 3 nano-particles reinforced Ti matrix composites increases with the increase in sintering time. The additions of Al 2 O 3 nano-particles improve the hardness values and corrosion behavior with the increase of sintering time.

In this study, hybrid alloys were obtained by casting method with alloy elements and additive such as Si and MoS2, which can be used instead of lead, and compared with Ecobrass and free cutting brass samples used in the market in terms of microstructure, mechanical, and machinability properties. The microstructures of lead-free hybridized brass consists of alpha, beta, and intermetallic compound which were confirmed by the results of X-Ray Diffraction analysis and Scanning Electron Microscopy-Energy Dispersive Spectroscopy. The hardness values of the beta phase in the microstructure are between 180 and 220 Vickers hardness. It has been observed that increasing the amount of beta prime phase also increases the hardness. The machinability of samples was evaluated in terms of surface roughness and chip formation. Chips obtained from samples after machining process were categorized according to ISO 6385-G1 standard. Chip morphologies were examined under optic microscope and scanning electron microscope. The surface roughness value of samples with MoS2 additives was found to be the lowest due to its lubricity effect. Moreover, morphologies, distribution of phases, and intermetallic compounds in the microstructure are found to have a great impact on the machinability and ultimate tensile strength.

The objective of this research is to investigate the effect of Zr, Nb and Ti additions on microstructural, mechanical and electrochemical properties of injection molded 316L stainless steel. The amount of additive powder plays a role in determining the sintered microstructure and all properties. In this study, 316L stainless steel powders used with the elemental Zr, Nb and Ti powders. The binders were completely removed from molded components by solvent and thermal debinding. The debinded samples were sintered at different temperature for 60 min. at different temperatures. Mechanical property, microstructural characterization and electrochemical property of the sintered samples were performed using tensile testing, hardness, optical, scanning electron microscopy and electrochemical experiments. Results of study showed that sintered 316L and 316L with additive powder samples exhibited high mechanical and corrosion properties in a physiological environment.

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