Liu Yingli

Spray Conform 7075 Al

Spray Conform is a near-net-shape technology that combines elements of spray forming and Conform. 7075 aluminum alloy rods were fabricated by spray Conform followed by retrogression and a reaging (RRA) heat treatment. The microstructure evolution and the mechanical properties of the spray Conform and the RRA spray Conform 7075 were researched. The spray Conform 7075 sample presents a microstructure with slight hardening precipitates within the matrix and at the grain boundaries, partially recrystallized regions, refined grains and low segregation of the main elements. The final microstructure at RRA aged conditions is mainly composed of fine nanosized and homogeneous precipitates of AlCu and MgZn2, more recrystallized regions and discontinuous precipitates separating out at grain boundaries. The microstructure, no matter the spray Conform 7075 or the RRA-7075, plays a critical role in achieving good mechanical properties combined with high stress-corrosion cracking resistance of the final products.