MECHANISMS AND PREDICTION OF FRACTURE TOUGHNESS ANISOTROPY OF HIGH STRENGTH Al ALLOYS
高强度变形铝合金断裂韧度各向异性的机理和预测

Contributions of weak grain boundary, cracking path deflection and grain boundary delamination to fracture toughness anisotropy of high strength Al alloys were evalu- ated based upon approaches of fracture mechanics and in conjunction with physical cracking mechanisms. The predicted results are close to those experimentally determined in the literature and in this work. The strong anisotropy of fracture toughness of high strength Al alloys is therefore attributed mainly to weak grain boundary cracking, cracking path deflection and grain boundary delamination. With the methods of this work, short--transverse fracture toughness values of some semi-products can be estimated from in--plane toughness values and corre- sponding fracture characteristics when it is difficult to be determined experimentally.