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.

Theoretical and Experimental Study on the Effect of Selected Parameters in a New Method of Extrusion with a Movable Sleeve

“…Studies investigating rotary forging focus on the effect of selected technological parameters (e.g., process fluctuations [18], the use of a mandrel [19], lubricating conditions [20]) on the stability of the process and product properties. Moreover, rotary forging is also investigated in terms of forging bimetallic products [21,22].…”

Design and technological capabilities of a CNC skew rolling mill

“…Nowadays, elongated axisymmetric parts of several hundred millimetres in length are produced by cross wedge rolling [1][2][3] or longitudinal roll forging (predominantly preforms for die forging processes) [4][5][6]. In turn, long parts (of up to several metres in length) are produced by open die forging [7,8] (they are produced individually or in smaller batches) and rotary forging [9][10][11] (they are higher accuracy parts produced in larger batches). Small elongated parts (with their lengths ranging from dozens to 200 mm) can also be produced by skew rolling in skew rolling mills equipped with rolls having helical impressions [12][13][14].…”

Cold forging of a hollow flanged part by an unconventional extrusion method

“…Another group of forming processes for hollow products includes processes in which the tools and/or workpiece perform the rotary motion. Rotary forming methods include: cross wedge rolling [22][23][24], rotary compression [25], rotary swaging [26,27], rolling extrusion [28,29]. These processes are characterized by high efficiency and are predominantly used for producing axisymmetric parts.…”