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In this study, kinetic examinations on boronized AISI 304 Stainless Steel samples were described. Samples were boronized in indirect heated fluidized bed furnace consists of Ekabor 1? boronizing agent at 1123, 1223 and 1323 K for 1,2 and 4 hours. Morphologically and typically examinations of borides formed on the surface of steel samples were studied by optical microscope, scanning electron microscope (SEM) and X-Ray diffraction (XRD). Boride layer thickness formed on the steel X5CrNi 18-10 ranges from 12 to 176 ?m. The hardness of the boride layer formed on the steel X5CrNi 18-10 varied between 1709 and 2119 Hv0,1. Layer growth kinetics were analyzed by measuring the extent of penetration of FeB and Fe2B sublayers as a function of boronizing time and temperature. The kinetics of the reaction has been determined with K=Ko exp (-Q/RT) equation. Activation energy (Q) of boronized steel X5CrNi 18-10 was determined as 244 kj/mol.

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In this study, the mechanical and wear properties of AISI 316L stainless steel implant materials, produced by powder metallurgy (P/M), were investigated. AISI 316L stainless steel powder was cold-pressed with 800 MPa of pressure and then sintered at 1200, 1250 and 1300°C for 30 min as three sample groups. The microstructure, and mechanical and wear properties of the resulting steels were investigated. Light optical and scanning electron microscopiese were used to characterize the microstructure of the steels. Room temperature mechanical properties of the steels were determined by hardness measurements and impact tests. Wear was determined using the pin-on-disc wear test, and the results were evaluated according to weight loss. The results indicate that the sintering temperature, time and atmosphere are important parameters that affect the porous ratio of materials produced by P/M. Sintering at high temperature can eliminate small pores and make the residual pores spherical. The wear tests showed that the wear of the AISI 316L stainless steel implants changed depending on the sintering temperature and load. Spherical pores in the samples increase the wear resistance. Moreover, decreasing the porosity ratio of these materials improves all of their mechanical properties.powder metallurgy, wear, 316L implant, mechanical properties Citation:Kurgan N, Sun Y, Cicek B, et al. Production of 316L stainless steel implant materials by powder metallurgy and investigation of their wear properties.

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In this study, Mg-0.5Ca alloy was produced in a newly designed unit during the metal injection molding process. 40?mD90 Mg powder and 500nmD90 Ca powder were used in accordance with injection molding and powder sintering rules. In the injection phase, Polyethylene-glycol (PEG) and Poly-methyl-methacrylate (PMMA) and stearic acid (SA) polymers act as binders and lubricants. In the experimental phase, X-ray Diffractometer (XRD), Thermal Gravimetric Analyze (TGA), Scanning Electron Microscope (SEM) equipped with Energy Dispersive Spectroscopy Mapping (EDS and MAP), and Vickers microhardness (HV) examinations were performed. The samples produced were subjected to the sintering process at different temperatures and times. Conventional powder sinter stages point, neck, and joining structures were obtained at different temperatures and durations. As a result, it was determined that Mg-0.5Ca alloy reached a metallic form with the specified polymer structure only at 600oC temperature and after 5 h sintering. Grain boundaries were formed in the sintered sample and the presence of the Mg2Ca phase was observed. The hardness of the metallic structure obtained was measured as 49.9 HV0.1 on average.

S teels with martensitic microstructure (low carbon) and high creep resistance can be used at high temperatures for a long period of time. One of the potential applications of these materials is thermal and nuclear power plants. Over the years, the demand on the service temperature level in these plants have increased. As a result, studies on the development of new steel-based materials with enhanced creep and corrosion resistance have soared. The graph shown in Fig. 1 shows the need for service temperatures and pressures depending on years. Steels with 9-12% Cr content have been started to be used in these applications since 1950s. These steels