Elastic moduli of boron carbide/copper composites from -40/sup 0/C to 800/sup 0/C by ultrasonic methods

An ultrasonic through-transmission technique for high attenuating materials was developed to determine the ultrasonic longitudinal and shear velocities in B/sub 4/C/Cu composites to 800/sup 0/C. Ultrasonic velocity data was used to calculate Young's modulus, shear modulus, and Poisson's ratio for the composites from -40/sup 0/C to 800/sup 0/C. 5 figures, 1 table

Ultrasonic longitudinal wave velocity in carbon-carbon Pitch and Pitch/M2 shape stable nosetip material from 70/sup 0/F to 5400/sup 0/F

A pulse echo method was used in two notched rods of carbon-carbon Pitch material and one rod of Pitch/M2 shape stable nosetip material to measure the temperature dependence of the longitudinal wave velocity from room temperature to 5400/sup 0/F. The velocity was constant to within 2% of the room temperature value for the Pitch parent material throughout the temperature range. For the Pitch/M2 material, the velocity increased to a maximum of 10% at 4000/sup 0/F and then decreased rapidly. Room temperature velocities in the principal directions of the composite are also given for the two Pitch rods, which showed a 15% decrease in velocity near the ends of both rods and near the side of one rod