Effects of warm saddle forging deformation on the reduction of second-phase particles and control of the three-dimensional mechanical properties of 2219 aluminum alloy rings

Severely segregated Al2Cu coarse second-phase particles (CSPPs) and uneven mechanical properties are the main problems in the manufacturing process of 2219 aluminum alloy large rings. A new method for the control of the three-dimensional mechanical properties (TDMPs) of the rings is proposed in the present study. The evolution law of the Al2Cu particles and the regulation mechanism of the TDMPs were investigated. The research revealed that optimizing the warm compression and rolling deformation can effectively reduce the quantity of CSPPs and regulate the TDMPs. With the increase of compression deformation (from 30% to 70%), the degree of the crushing and passivation of CSPPs was found to increase, the area fraction of the CSPPs decreased by 72.6%, and their roundness factor increased from 0.694 to 0.845; in the compression deformation process, high-density dislocations can effectively promote the crushing, dissolution and diffusion of Al2Cu particles, thereby enhancing the precipitation driving force of the strengthening phase during aging, resulting in a 99% increase in the quantity of the theta' phase. When the compression deformation was 20% at 510 degrees C and 50% at 240 degrees C, the tensile strength, yield strength, and elongation of the ring in the radial direction were found to increase from 392 MPa, 287 MPa, and 6.4% to 468 MPa, 358 MPa, and 11.2%, respectively; moreover, the anisotropies of the three indicators of the rings were reduced by 32.6%, 54.0%, and 38.9%, respectively.

Automated summary

A new method for controlling the three-dimensional mechanical properties of 2219 aluminum alloy rings was proposed in this study, by optimizing warm compression and rolling deformation to reduce the quantity of coarse second-phase particles and regulate the properties. The research revealed that compression deformation can promote the crushing and dissolution of particles, enhancing the precipitation driving force of the strengthening phase during aging.