The study was ca*ied out by rcinrorcing trre resin matrix
material which was (unsaturated polyester)Ly using alumna powder (Al2o3)with particle size (75)pm to prepare cornposite
materials r,vith different volume fractions(3%,7yo,rT%o) by usi,g
hand Lay -up rnethod.
Some dynamic mechanical properties was studied of the
prepare composite sampres by using urtrasonic technique as a
nondestructive testing
After that the transite time of the ultrasonic waves which
passes through the composites was measured, from this
measurernent the compressional and shear velocity was
calculated and from these verocities som of trre dynamic
mechanical properties was calculated, these properties included
dynamic Young's modulus@d),Shear rnodulus(G),dynamic
Poisson's ratio(p),The dynamic mechanical properties were
studied with respect to volume fraction and denslty