Jaw Trajectory Design And Research On Stretch Bending Process Of Aluminum Alloy Profile With Irregular Cross-section

As an important metal forming technology, stretch bending process can obtain smallerspringback and better quality, it is easy to form large complicated structure. Stretch bendingtechnology based on jaw trajectory has a short design circle, high forming precision and stability.It can meet the high efficiency and low cost requirements of the international market very well.The article designs the jaw trajectory of different target profile tapes based on the pattern ofP-M-P. The article dose a research on2d and3d stretch bending with FEA simulation softwareand analyze the influence of different process parameters on forming quality. Specific contents asfollows:(1) Establish model, set boundary conditions according to jaw trajectory and set up6005-T4material model through uniaxial tensile test. Conduct the finite element simulation withABAQUS/Explicit and Double.(2) The article designs the jaw trajectory of four target profile types including constantcurvature trajectory design, sectional curvature trajectory design, continuous variable curvaturetrajectory design and3d curvature trajectory design. In order to avoid reversing deformation,reducing spring, this article puts forward the parameter of bend-stretching length to optimize thetrajectory calculation formula.(3) Conduct the numerical simulation based on2d sectional curvature curved trajectorydesign. Compare the influence law of different pre-stretching, bend-stretching length, transitionzone length and speed. In additional, research on the defects inhibition law of differentpost-stretching, filling pressure and three types of internal padding. The results showed that withthe increase of pre-stretching, bend-stretching length and post-stretching, springback afterunloading released. Profile filled with whole pad gets a smaller distortion of cross-section. Carryout a practical experiment, the comparison showed that the results achieved by numericalsimulation correlated well with the test results.(4) Conduct the numerical simulation based on3d curvature curved trajectory design. Compare the influence law of different pre-stretching, bend-stretching length, transition zone andpost-stretching. The results showed that spring-back released with the pre-stretching,bend-stretching length and post-stretching increased. It can reduce cross-section distorsionapparently to increase transition zone, to reduce bend-stretching length. Filling the cavity withpolyester makes an obvious improvement on cross-section distorsion.