Examining the transformation of grain sizes of some metal-matrix ceramics with carbide by using ultrasound

This study is designed to determine the relationship between the mean grain size of some carbide based metal-ceramic composites and the ultrasonic method at sintered temperature.The content comprises of two parts; samples of the comparison between coated and non-coated and the samples of the comparison between carbide compounds. In the first part, coated tungsten carbide-nickel (WC-Ni) powder was sintered using electroless nickel coating method and non-coated tungsten carbide-nickel (WC-Ni) powder was sintered using powder mixing method at temperatures between 1000°C and 1300°C. In the second part tungsten carbide-iron-nickel (WC-Fe-Ni), silicon carbide-iron-nickel (SiC-Fe-Ni) and boron carbide- aluminium-nickel (B4C-Al-Ni) powders were prepared by sintering at various temperatures with electroless nickel coating method. Ultrasonic velocity and attenuation values were measured by using probes of 2 MHz and 4 MHz and their relationship with the grain sizes were examined.As a consequence, it was observed that mean grain sizes increase depending on the sintered temperature and phase transformation takes place at 1300°C and coating was fulfilled when we look at seen in the graphic that ultrasonic velocity increases while attenuation values decrease in accordance with both the mean grain size and the sintered temperature.Keywords: Ultrasonic Velocity, Attenuation, Mean Grain Size, Electroless Ni Plating, Metal-Ceramic Composite Materials