Titanium alloy profile bending components—known for their low density, high strength, corrosion resistance, and excellent high-temperature performance—have become essential lightweight structural parts in the aerospace field. They are widely used in fuselage door frames, load-bearing beams, long stringers, and aircraft engine bulkhead structures, significantly enhancing safety, maneuverability, and fuel efficiency. With broad application prospects, the demand for high-precision titanium alloy components continues to rise rapidly.
However, due to the high deformation resistance, poor plasticity, and limited formability of titanium alloys at room temperature, advanced thermal forming methods are typically required. Achieving precision plastic forming and shape-performance integration for these lightweight, high-strength structures has long been a core research challenge in the metal forming field.
As China’s large aircraft and new high-speed transportation programs demand more advanced aerodynamic geometry, structural strength, and spatial efficiency, high-performance 3D curved profiles are increasingly used in high-end equipment manufacturing. Yet current domestic titanium alloy bending processes still cannot fully meet the forming requirements for such complex 3D components. Therefore, developing a process and equipment capable of achieving precise three-dimensional bending of titanium alloy profiles—supported by advanced CNC bending machines and metal bending machine technologies—is of great significance for next-generation high-speed transportation manufacturing and also serves as one of our company’s core R&D directions.
Through internal research and extensive collaboration with Professor Li Xiaoqiang’s team at Beihang University, we gained deeper insights into the thermal stretch-bending mechanisms of titanium alloy profiles. At present, titanium profile bending mainly relies on hot stretch-bending techniques. Because the forming process involves multi-field coupling under high-temperature conditions—complex boundary constraints, uneven temperature distribution, microstructural evolution, and extreme sensitivity of deformation to process parameters—recent research has focused heavily on process optimization.
Existing thermal stretch-bending equipment, including conventional CNC bending machine systems, pipe bending machines, and integrated-die bending machines, can generally achieve only planar 2D bending due to the inherent limitations of monolithic dies. This restriction makes it difficult to achieve complex three-dimensional curved geometries.
To overcome these bottlenecks, Professor Gao’s team introduced a current-assisted heating energy field into a flexible multi-point 3D stretch-bending process. They proposed a novel multi-point 3D hot stretch-bending method designed for difficult-to-form materials such as titanium alloys and successfully achieved 3D bending of TC4 titanium alloy L-shaped profiles. Their research provided significant inspiration for our technological development and application of advanced CNC tube bending machine manufacturing solutions.
To understand this technology clearly, we can review the fundamentals of the multi-point 3D hot stretch-bending process. As illustrated in the schematic, the profile is first heated to its target temperature through current-assisted heating. A flexible multi-point die defines the spatial target geometry. Based on deformation-superposition principles, the heated profile is clamped and initially bent horizontally. The multi-point die then moves synchronously in the vertical direction while its discrete units rotate freely to follow the profile’s curvature. The profile remains fully enveloped by the die throughout the forming motion until it reaches the predefined trajectory. Current-induced high temperature increases material plasticity, expands the forming window, and reduces deformation resistance—crucial for hard-to-form alloys. Meanwhile, the flexible multi-point die overcomes the limitations of integrated dies and enables truly complex 3D bending.
This method achieves complex spatial bending of difficult metal alloys through the combination of current-assisted heating and flexible multi-point forming—an innovation that also drives improvements in modern steel bending machines, hydraulic bending machines, sheet metal bending machines, and plate rolling machine technologies.
Through continuous effort and the pursuit of technical excellence, we successfully applied this technology in commercial practice and completed a full technical proposal presentation for AVIC XAC (Xi’an Aircraft Industry, Aviation Industry Corporation of China). Shanghai Camille Technology will continue to pursue excellence and provide our customers with industry-leading forming solutions and advanced bending equipment technologies.
