METHOD FOR HEAT TREATMENT OF SEMIFINISHED PRODUCTS AND ARTICLES OF ALUMINUM-BASE ALLOY

FIELD: metallurgy of aluminum-base alloys, namely Al-Mg-Li alloys, possibly for making semifinished products and parts in metallurgical and machine engineering plants. ^ SUBSTANCE: method for heat treatment of semifinished products and parts of aluminum base alloy comprises steps of quenching and multiple aging; performing quenching at 400-535 C; after quenching realizing at least one heating stage at 375 -535 C; after each heating stage realizing deformation with rate 0.5 -85% at 20 - 400C; performing aging by four stages: during first stage heating at 190 - 210 C for 1 - 6 h, during second stage heating at 80 - 90 C for 3 - 12 h, during third stage heating at 110 - 185 C for 10 -48 h and finally heating at 90 -110 C for 8 - 14 h. It is possible after quenching to perform heating at 375 - 400 C for further deformation at the same temperature with deformation rate 5 -45%; to perform heating at 375 - 400 C after quenching for further deformation with rate 0.5 - 85% at 20 -40 C; to perform heating after quenching at 375 -400 C for further deformation with rate o.5 -85% at 20 - 40 C, then -heating at 400-535 C for further deformation with rate 0.5 -5% at 20 - 40 C. ^ EFFECT: possibility for making semifinished products and parts with improved ductility and surface quality at keeping their thermal stability. ^ 4 cl, 2 dwg, 1 ex