Effect of Forging Times on Structure and Mechanical Properties of 7A04 Al Alloy
The tensile test, impact test, hardness test and microstructure analysis were used to investigate the mechanical properties and structure of 7A04 aluminium alloy under different forging times. The results show that, with the increase of forging times, because the crystal grain thins unceasingly, the intension and hardness rises gradually, when the forging times is four, the crystal grain has completely dynamic recrystallization, the intensity and hardness are biggest. The forging times increase unceasingly, the intensity reduces. Because the microcrack exists in the organization,the plasticity reduces with the crystal grain thinning. The impact power reduces with the forging times increasing, when the forging times is three, the impact power is biggest, then increases. It is determined that one and four times are appropriate forging times for the 7A04 aluminum alloy. This experiment provides basical theory for forging technology of this aluminium alloy.