The applications of aluminum alloy rings as the critical connection, transmission, rotation and supporting components in the bearing and gear rings for wind power equipment and the heavy launch vehicle storage tank, and in the reinforcing rings for pressure vessels and nuclear reactors are increased dramatically. The production of aluminum alloy rings is a hot working process with an energy-extensive consumption. The current techniques are as follows: (i) thick-plate rolling, bend rolling, welding forming by a half. The microstructures are characterized by a weak performance in the welding positions. The rings cannot meet the requirements in long-term service under harsh conditions such as heavy loading, impact, high temperature and strong corrosion. (ii) Cast ingot blank, multi-directional forging, trestle reaming or ring rolling. Due to the cogging, forging and punching, the long process and huge investment in equipments are caused. The repeated heating results in extensive-energy consumption and material wasting, which is not conducive to the environmentally friendly production. Aluminum alloy rings is a major strategic demand for the deep space exploration. The challenges include large geometrical dimension, high shape precision, low structural stiffness and extreme service conditions are presented. Up to now, the large aluminum alloy rings with a diameter of 3-10 m are hot rolled. The couple of deformation-heat transfer-microstructure evolution leads to the complicated development in multi-pass, continuous loading and unloading partly, non-uniform deformation and inhomogeneous microstructure with multi-fields and multi-factors. To realize the hot ring rolling of aluminum alloy, the overall stiffness and the stability of rings should be controlled firstly. Secondly, the integrated control of radial-axial dimensions, section profile and geometric accuracy need to be realized. Thirdly, the required microstructure and properties in each direction of the hot-rolled rings should be achieved. The preparation of aluminum alloy ring blank is the basis of hot rolling and its integrated control on shape and performance. The coarse microstructure in large-sized casting blank can be refined effectively and the network eutectic compound can be broken by multiple forging technology. The microstructures are modified and then the superior ring blank can be provided to hot ring rolling. The intelligent modeling and simulation of radial-axial rolling of aluminum alloy ring and radial-axial rolling driven by rolling force of aluminum alloy ring are developed. The problems in the discordance of radial-axial deformation areas, the weak stiffness of rings and the instability of hot rolling are solved. The motions of rolls are driven by the control targets. According to the strain and aging precipitation strengthening after hot-rolled, the strength is enhanced and the residual stress is eliminated. The superior mechanical properties in radial, axial and circumference directions of rings are obtained. Aiming at the disadvantages of the current techniques, the compact cast-rolling compound forming is studied in this paper. The ring blank produced by sand casting or centrifugal casting is directly hot rolled. The precision of geometrical dimension and the improvement in the microstructure and performance of ring blank are realized simultaneously. The mechanism in the control of microstructure and performance of ring blank is revealed based on textural development. The theoretical basis of integrated manufacturing in compact cast-rolling forming of aluminum alloy rings and duplex-metallic rings will be given. In this study, the status of integrated manufacturing in shape/properties of aluminum alloy ring is presented. The preparation of aluminum alloy ring blank, the hot ring rolling of aluminum alloy and the integrated control of microstructure and performance in aluminum alloy ring are briefly summarized. The challenges in the integrated control on shape and performance of rectangular/profile section aluminum alloy rings are emphatically elaborated. The trends and research emphases of manufacturing in aluminum alloy ring are proposed. The development of theory and technology of integrated control on shape/properties in hot rolling of aluminum alloy ring/aluminum-based bimetallic laminated ring will be promoted. © 2021, Materials Review Magazine. All right reserved.
