1987 Volume 35 Issue 400 Pages 260-265
Based on the results of tensile and fracture toughness tests and AE detecting method, mechanical properties of Al-Li alloy are examined. Specimens tested were heat-treated in three different conditions, i. e., T42, T6, and T8 ones. The tensile characteristics and fracture toughness of the alloy are discussed in detail. Any effect of cold-rolling on the fracture toughness could not be founded. Fracture surface of T42 specimens was that of transgranular, while those of T6 and T8 specimens were entirely intergranular and secondary cracks perpendicular to crack plane were observed. The fracture mechanism of this alloy is proposed according to the AE activities during the fracture toughness test and the crack jump size calculated using the compliance method. The fracture toughness K1C is also calculated by a ductile fracture model, which shows a good agreement with experimental results.
