A new net-shape plating technology for axisymmetric metallic parts using rotary swaging

Abstract

This paper summarizes the research work aimed to elaborate a new plating method for axisymmetric metallic parts by precision cold forming on rotary swaging principle and, on this basis, to develop an environmentally friendly technology for net-shape plating. The new technology is intended to create parts with the basic structure made from cheap materials with high fatigue strength, on which, in areas where they require different characteristics (low friction coefficients, greater hardness, greater corrosion resistance, etc.), a layer of more expensive materials that provide these features is applied. At first, the new method of plating through rotary swaging was developed and the net-shape plating technology was preliminarily designed. Then, the experimental technology was analyzed and optimized employing process simulation by finite element method (FEM). A nonlinear finite element analysis (FEA) package, MSC.Marc/Mentat, was used. The full 3D FEM model established in this study eliminates some of the limitations encountered in the previous works using the real movement curve for dies and accurate boundary conditions. The model running tests indicate that the relative positioning between base workpiece and coating tube is of crucial importance in this application. Finally, practical experiments were carried out, the results been used for validation of the 3D simulation model, for physical-mechanical characterization of the joining between base part and coating layer and for technology design finalization. A good agreement between experiments and simulation was found. Also, the experiments indicate that the joint is more tightened when the inside workpiece has a yield strength greater than the outer workpiece.