High-performance stamping forming process of 6061 aluminum alloy with pre-hardening

The 6061 aluminum alloy billets are subjected to solution quenching treatment under a solution heat treatment condition of 550 ℃ for 30 min. After quenching， the billets are artificially aged at 140 ℃ for 6 h to 18 h to obtain pre-hardening （PH） billets. The formability and mechanical properties of the pre-hardening 6061 aluminum alloy billets are evaluated using room-temperature Erichsen cupping tests and uniaxial tensile tests. Additionally， the stamping trials for hat-shaped beam components are conducted to verify the feasibility of this technique for engineering applications. The results show that the yield strength （YS） of the PH-12 h pre-hardening billets is 186 MPa higher than that of the O-temper billets， and the tensile strength （TS） is 215 MPa higher than that of the O-temper billets， while the elongation （EL） and cupping values are comparable to those of the O-temper billets. The PH-18 h pre-hardening billets exhibit a maximum tensile strength of 391 MPa after 10% deformation， significantly exceeding that of the T6-temper aluminum alloy， demonstrating that the pre-hardening billets possess excellent strength-ductility balance. Furthermore， the hat-shaped beam components formed from pre-hardening billets exhibit tensile and yield strengths superior to those of the T6-temper aluminum alloy.