HOT CRACKING SUSCEPTIBILITY OF AL-CU-LI AND AL-CU-LI-MN ALLOYS

The effect of Li content (up to 4%), Cu content (up to 5%), and Mn con tent (up to 1.4%) on the hot cracking susceptibility of Al alloys cont aining Li was investigated. The usual tests, principally the measureme nt of crack length in ring castings, were used To evaluate the hot cra cking susceptibility of the alloys. The values of linear shrinkage and elongation to failure in the brittle temperature range in the solid-l iquid condition were compared. An increase in Li and Cu content ill th e AI-Cu-Li system results in a decrease in the hot cracking susceptibi lity corresponding to a rise in the elongation to failure in the britt le range in the solid-liquid condition. The addition of Mn increases t he hot cracking susceptibility associated with a decease in elongation to failure in this temperature range. (C) 1995 The Institute of Mater ials.