Optimization of Microextrusion Preforming Using Taguchi Method

Abstract

Micropin head geometry significantly influences surface contact and electrical conductivity. In this paper, the preforming process of extrusion is investigated to establish it as a viable process for microforming. Here, the numerical simulations using DEFORM-3D software are used to examine the effect of preformance and pin shape on the extrusion of microbrass pins with a minimum diameter of 0.88 mm under several design parameters. These parameters are planned with the Taguchi method and help to discover better conditions for the minimum extrusion loads. For obtaining the required parameters to enable the finite element software, a compression test is first performed to determine the true stress and true strain curve of the materials. The result acquired from the experiment is compared with the simulation outcome and verified the accuracy. The consequences show that the optimal microextrusion forming conditions appear on stage rod length 0.015 mm, extruding angle 60°, upper front-end taper 60°, and bottom stage angle 60° to minimalize the forming load, and the dimensions of the deformed micropin reveal a good identification with the simulation. The study hence shows a potential tool for the combination of Taguchi method and finite element software to analyze the microforming process in the fastener industry.

Wear Improvement of Tools in the Cold Forging Process for Long Hex Flange Nuts

“…According to different quality characteristics, various S / N ratio formulas are formed, including nominal-the-best, smaller-the-better and larger-the-better. The smaller-the-better was applied in this study for the optimization simulation to search for minimum wear, the S / N ratio [14,15] being: $S/N=-10 \text{log}\left({\overline{\text{y}}}^2+{\text{S}}_{\text{n}}^2\right)$ where y i is the measured value and n the number of repeated measurements.…”

“…The die set structural analysis problem was formulated as a contact problem considering both shrink fit and preloaded clamping, solved iteratively by a varying penalty method. Hsia [14] used FEM DERORM-3D software to simulate the 3C micro-pin forward extrusion and forging process. His study simulated the forward micro-extrusion of a workpiece, discussed the differences between the simulated stage process and the experimental process and determined effective stress-strain and material flow properties after extrusion, as well as the upper punch reaction when the material was formed.…”

Accuracy of Model Force Prediction in Closed Die Coining Process

“…In their paper, the analysis of the micro-geometry forming was done in the closed coining die with the assumed plane state of strain. Many papers are concerned with the study of the size effects in micro-forming, [7] and [11] to [13], and their influence on the various microforming processes, such as micro-indentation [14], micro-imprinting [15], micro-extrusion, [16] and [17], and the bulk forming processes of sheet metal, [18] and [19]. However, relatively few works deal with the coining process and the real problems of production, such as residual stress, elastic deformation and incomplete die filling, [1] to [3], [10] and [20] to [22], lubricant residues and surface damage [23], and tool development and manufacturing, [24] and [25].…”

Multi-stage forging on torx-pin screw with high torque

“…Shih et al [3] and Hsia [4] use the simulation analysis software, except for greatly increasing the efficiency of making dies, shortening the production cycle of new products and increasing the lifespan of dies, it also can provide new-coming designers with the prompt understanding of tool design, the analysis of defect and the improvement of simulation. Therefore, it can save massive time in preprocess schedule to further upgrade the design level of dies.…”