Serrate4d flow in aluminium alloys containing lithium

摘要

Serrated-flow characteristics have been studied in binary Al-Li-alloys with different compo- sitions. Load-elongation curves seem divided into two sections of which the first is weakly, the second heavily, serrated. The initial weak serrations, which diminish with ageing, arise probably from the inter- action of dislocations with lithium atoms in solid solution. It is proposed that the larger serrations which appear later on the load-elongation curve (if the elongation to necking is large enough to allow them to develop), and which increase in size with progressive ageing, are connected with shearable δ'-precipitates.