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Ni-Fe metal matrix composites reinforced with WC have been fabricated by microwave sintering at various temperatures. A uniform nickel layer on WC and Fe powders was deposited prior to sintering using electroless plating technique, allowing closer surface contact than conventional methods such as mechanical alloying. The reactivity between WC and Fe powders to form carbides of Fe is controlled through Ni layer existing on the starting powders. A composite consisting of quaternary additions, WC, Ni and Fe was prepared at the temperature range 500°C-900°C under Ar shroud. X-Ray Diffraction, SEM (Scanning Electron Microscope), compression testing and hardness measurements were employed to characterize the properties of the specimens. Experimental results carried out for 900°C suggest that the best properties for omax and hardness (HV) were obtained at 900°C and the microwave sintering of electroless Ni plated WC and Fe powders is a promising technique to produce ceramic reinforced composites.

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The scope of this study, that is, the effect of the elastic modulus obtained by ultrasonic method on the physical and mechanical properties of tungsten carbide (WC)-based ceramic–metal composites, which have Ni and Co metallic binder composition produced by powder metallurgy and represented by high strength and hardness criteria, was investigated. In order to obtain composite samples in the study, it was sintered in a microwave furnace at different temperatures to combine the powder particles prepared at the rate of 60% Ni, 20% Co, and 20% WC by weight. Then, the velocities and longitudinal attenuation values of longitudinal and shear ultrasonic waves along the composite sample were measured using the ultrasonic pulse-echo method. The elastic modulus of the composites was determined using ultrasonic velocities and sample density. Hardness testing, scanning electron microscopy (SEM), and X-ray diffraction (XRD) analyses were also performed. The results show that the elastic modulus increases with the increase in sintering temperature and ultrasonic wave speeds, but decreases with the longitudinal attenuation value, considering the SEM images and XRD analysis. There is also a linear relationship between elastic modulus and stiffness.

In this study, SiC reinforced nickel matrix composites, microwave at different temperatures It is produced by sintering in oven. Nickel deposition on SiC powders was achieved by using electroless nickel plating technique. It is sintered at temperatures between 500°C, 600 °C, 700°C, 800°C and 900°C under Ar atmosphere. XRD, SEM (Scanning Electron Microscope), pressure test and hardness measurements were used to characterize the properties of sintered samples in microwave furnace. The experimental results, maximum compressive strength (σmax) and hardness (HV) were carried out at 800 °C. Microwave sintering of Ni-coated SiC powders without electric current can be a promising technique for producing ceramic-reinforced nickel composites.

Nickel (Ni) matrix reinforced with boron carbide (B4C) has been produced by conventional furnace sintering at various temperatures. A uniform Ni layer on B4C powders was deposited prior to sintering using electroless plating technique, allowing close surface contact between particles. A composite consisting of quaternary additions, a ceramic phase, B4C, within a matrix of Ni and AstaloyCr-M powders has been prepared at a temperature range of 1000°C–1200°C under Ar shroud. X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM) study, compressive testing, and hardness measurements were employed to characterize the properties of the composite. Experimental results showed that the best properties as compressive strength σmax and hardness (HB) were obtained at 1150°C. Wear resistance was relatively higher than cast iron.

In this study, a composite containing WC (Tungsten Carbide) and Ni was produced by two different processing routes. Electroless Ni coated WC powders were consolidated and sintered at 1200 • C. Diffusion bonding couples of WC(Ni)-electrolytic Cu, WC(Ni)-AISI 316 stainless steel and WC(Ni)-WC(Ni) were manufactured by using a preloaded compression system under Ar atmosphere. Diffusion bonding was carried out at varying bonding temperatures; 750 • C for (WC)Ni-Cu diffusion couple and 1200 • C for (WC)Ni-(WC)Ni and (WC)Ni-AISI 316 stainless steel diffusion couples. Standard metallographic techniques, Scanning Electron Microscopy and a shear test were employed to characterize the microstructure of bondline and mechanical properties of each diffusion couple, respectively.