The Effect of Mechanical Properties on the Ultrasonic Velocity Of Ceramic Based Composites Fabricated By Electroless Coating Technique

Abstract

The scope of the present study is to investigate the change of ultrasonic velocity with the physical and mechanical properties of Ni-Ti-WC composites. Since the materials used in the aerospace and automotive industries are exposed to high temperatures, friction and high stresses, the need for metal matrix composite materials used in manufacturing applications such as cutting discs and inserts has increased rapidly. Ni-Ti metal matrix composites reinforced with WC were circularly shaped in uniaxial hydraulic press. A mixture of 30% Ni, 2% Ti and 68% WC powders was sintered at 1000°C-1400°C with argon atmosphere in a tube furnace and were fabricated by electroless plating technique. XRD (X-Ray diffraction, SEM (Scanning Electron Microscope), compressive testing, hardness and ultrasonic velocity measurements were employed to investigated the mechanical and physical properties of specimens. Experimental results showed that ultrasound velocity values increased polynomial linearly with increasing sintering temperature. In addition, the fact that the highest sintering temperature resulted in 429.1HV hardness at 1400°C is an indication that the structure has become more robust and compact. The change in ultrasonic velocities with increasing sintering temperature is evidence of a better bonding of the structure.