Aluminum alloy extruded profiles are suitable for body middle beam structural parts. The structural design of the parts is flexible and convenient for the expansion and upgrading of the model. Aluminum alloy extrusion profiles can form closed complex sections, effectively improving the rigidity and strength of parts. The development cost of extrusion die is low, the cycle is short, the production efficiency is high, and the material utilization rate is high.
The following describes the application of aluminum alloy profiles in the body and parts system:
(1) Selection of parts materials. Generally, the body structural parts have high requirements for strength and plasticity. The most widely used material is 6 series aluminum alloy, which is strengthened by heat treatment and has good comprehensive performance. Front and rear impact beams, front and rear longitudinal beams, sill beams, seat crossbeams, etc., cross car Beam, referred to as CCB), battery pack frame and other parts system mostly use 6 series aluminum alloy, such as 6082, 6063, 6061, 6003, 6005, etc., and 6082 is mostly used when the collision strength is high, and 6061 and 6063 are mostly used when the collision energy absorption deformation is high, such as the energy absorption box of anti-collision beam and front and rear longitudinal beams. Aluminum alloy has good heat dissipation effect and is widely used in the heat exchange system of automobile, such as 3003, which has excellent extrusion performance and can realize the extrusion forming of harmonica tube with a wall thickness of 0.5mm.
(2) Section design principle of parts. The section structure shall be symmetrical as far as possible; the cavity shall be uniform and not too small, otherwise it is difficult to extrude; the wall thickness shall not be too thin, and the fillet shall be as large as possible, so as to facilitate the flow of materials and prevent extrusion defects; the mature section shall be adopted as far as possible.
(3) Part size accuracy control. Due to the small elastic modulus of aluminum alloy, the springback of profile after deformation (such as stretch bending, roll bending, etc.) is relatively large, and the dimensional accuracy is difficult to control, the flat structure should be applied as far as possible to avoid large curvature bending structure of parts, otherwise the shaping process should be increased after forming. Thermal deformation also occurs during aging treatment.
(4) As far as possible, riveting or low heat input welding processes, such as laser welding and CMT (cold metal transition welding), shall be adopted to prevent thermal deformation.