1. Composite Materials Laboratory, Central Metallurgical Research and Development Institute (CMRDI), P.O. Box 87, Helwan, Cairo, 11911 EG (Corresponding author), e-mail address: ADAOUDeg@yahoo.com
2. Composite Materials Laboratory, Central Metallurgical Research and Development Institute (CMRDI), P.O. Box 87, Helwan, Cairo, 11911 EG.
3. Materials Department, Univ. of Wisconsin–Milwaukee, 3200 N. Cramer Street, Milwaukee, WI 53201 US.