Research On The Deformation Regularity Of Embedded Cold-pressing Joining With Dissimilar Sheets

The attention of environmental issues increases with the development andprogress of society. Driving by the pursuit of energy-saving emission reduction, agreat many of new materials and structures have been applied in the area ofaerospace and automobile manufacturing. As one of lighten weight approaches,joining of dissimilar materials is getting the common focus of researchersgradually. Compared with laser welding and friction stir welding, the mechanicaljoining methods (screw joint, riveting and stamping connection ect.) have moreadvantages on the dissimilar sheets’ joining bottleneck problems such as largedifference of thickness and more sheets.This study proposes embedded cold-pressing joining method for enhancingthe normal carrying capacity and reliability of dissimilar sheet joining. Thejoining technique forms interlock joining structure which is based on one sheetdeformed and embedded into the hole of another sheet after loads applied onjoining area. Three different joint structure schemes are designed, such asoverlap-embedded, interaction-embedded and jack-embedded. Commercial purityaluminum1100and stainless steel304are employed in this paper. Joiningexperiment and joining strength test are performed on the css-44300universaltesting machine.First in this article, dissimilar sheet cold-pressing joining process is dividedinto three stages that are adjusting, stitching and embedding. The leading factorsare discovered and expounded deeply, combing with deformation joiningcharacteristics of different stages. At the same time, the effect of pressing, holestructure and punch reduction on dissimilar sheet cold-pressing joining process and quality is also researched. Finite element modelling is employed to studyplastic deformation characteristic rule, metal flow behavior and embedded fillingbehavior on the joint area during different schemes’ joining process. Experimentis adopted to research the macroscopic morphology and variation of width andthickness. And then the process optimization is realized. It analyzes the processtechnology and ensures the mode and internal mechanisms of failure combinespecific technology process.The study results indicate that aluminum sheet has a tendency to flow andembed in strain steel sheet’s prepared hole under the pressure in differentschemes. Meanwhile, the thickness of joint area decreases from symmetry planeto two sides, and there is an inverse relationship between thickness and press.The joint strength of jack-embedded is higher than other two schemes throughthe comparison with joint strength of three cold-pressing joining schemes.