Examining with the sintered temperature of mean grain size of B 4 C-Al-Ni composites by ultrasonic techniques

Abstract

Hard, tough, lightweight boron-carbide-reactive metal composites, boron-carbide-aluminum composites, are produced. The ultrasonic velocity and attenuation were measured on B4C-Al-Ni ceramic-metal composites, which are sintered in the temperature range 500-1200°C, by using the pulse echo method. Ultrasonic velocity, ultrasonic attenuation and rate of screen heights of successive peaks were determined according to the pulse-echo method by using 2 MHz and 4 MHz probes. It was observed that the mean grain size of samples has been changed with the sintering temperature. The velocity was found to be pretty sample dependent at room temperature and increased with increasing sintering temperature. The ultrasonic attenuation at room temperature was found to be more sample dependent. The sintering temperature variation of ultrasonic attenuation exhibited broad minimum values around 1200°C and sharp maximum values at 500°C. The increase observed in the temperature variation of longitudinal velocities and attenuation has been qualitatively explained with the help of the temperature variation of decrease value.