Influence of copper content on the fracture toughness of type D16 alloys

Abstract

1. With a reduction in copper content from 4.2 to 3.1% the fracture toughness KIc of type D16 alloys increases by about 30% practically independently of the type of semifinished product, aging cycle, or sample orientation. 2. After artificial aging at 190 °C for plates in the VD direction the value of KIc is more and in the DP direction somewhat less than for bars. 3. An increase in aging time of D16 type alloys from 8 to 16 h at 190 °C leads to a decrease in fracture toughness which is greater for plates than for extruded bars.