APPLICATION OF AN INTERMETALLIC COMPOUND TI5SI3 TO FUNCTIONALLY GRADED MATERIALS

Ti-Ti5Si3-functionally graded materials (FGMs) have successfully been fabricated by utilizing bonding through a eutectic reaction which occu rs between Ti and Ti,Si,, where Ti,Si, was employed because of its hig h heat and oxidation resistance. The bonding by the eutectic reaction has been investigated to bond a plate of pure Ti and of Ti,Si, togethe r. A compositionally and microstructurally graded region, where the vo lume fraction of Ti5Si3 changes continuously, has been obtained betwee n these plates after bonding at 1613 K. Subsequently, a similar method has been utilized to make coating on Ti plates and semi-round rods th rough the eutectic reaction with Ti5Si3 powder. In this case, a simila r compositionally and microstructurally graded region has been obtaine d. No macroscopic defects, including observable cracks, have been dete cted in these FGMs fabricated. (C) 1997 Elsevier Science S.A.