Burnt Microstructure and Properties of 7003 Aluminum Alloy
The microstructure and properties of 7003 aluminum alloy with and without burning have been investigated by means of electronic tensile machine, optical microscope (OM) and scanning electron microscopy (SEM). The results showed that the burning level of 7003 alloy increases while the ultimate tensile strength (UTS) and yield strength (YS) for the alloy decrease with increasing the solution temperature. When the solution temperature is higher than 763 K, the UTS and YS for the alloy decline fast with wide-range. The remelting structure, namely burnt structure, appeared on the grain boundaries in 7003 aluminum alloy and then weaken grain boundary, hence resulting in the transition of fracture surfaces from transgranular fracture to intergranular fracture.