2618 heat-resistant aluminum alloy is an Al Cu Mg alloy that introduces intermetallic phase al9feni phase by adding an appropriate amount of Fe and Ni. In order to improve the microstructure and mechanical properties of the alloy, a new thermomechanical treatment process of "solid solution treatment + ECAP + short-time recrystallization + peak aging treatment" has been developed for 2618 aluminum alloy Chalco aluminum, aiming at obtaining 2618 aluminum alloy with very fine grain structure, The alloy has better comprehensive mechanical properties.
(1) recrystallization annealing of
2618A aluminum alloy profile deformed by ECAP can obtain relatively fine recrystallized grain structure of 2618 alloy. The best recrystallization annealing process parameters are: holding at 530 ℃ for 5 ~ 30min.
(2) the grain structure of
2618A aluminum alloy profile after aging is not sensitive to the recrystallization annealing time. The recrystallization annealing of 2618 alloy after ECAP deformation for 5 ~ 15min can meet the requirements, and the average grain size of the alloy can be controlled at 25 μ M or so.
(3) using solid solution + ECAP + short-time recrystallization annealing + peak aging treatment can improve the comprehensive mechanical properties of
2618A aluminum alloy profile, which is a beneficial exploration of thermomechanical treatment process to improve the comprehensive mechanical properties of aluminum alloy.
2618A alloy is characterized by high strength and certain heat resistance. It can be used as 150? Working parts below C. Temperature higher than 125? C. The strength of 2218 alloy is higher than that of 7075 alloy. The formability is better in thermal state, annealing and new quenching state, and the strengthening effect of heat treatment is remarkable, but the requirements of heat treatment process are strict. Poor corrosion resistance, but it can be effectively protected by coating with pure aluminum; Cracks are easy to occur during welding, but special processes can be used for welding or riveting.
2618A aluminum alloy profile is widely used in aircraft structures, rivets, truck hubs, propeller components and other structural parts.
