A Study on Formation Process of Secondary Upsetting Defect in Electric Upsetting and Optimization of Processing Parameters Based on Multi-Field Coupling FEM

Abstract

The electric upsetting process is an excellent electrically assisted preforming technique with electrical-thermal-mechanical multi-field coupling characteristic. The secondary upsetting defect in electric upsetting with inappropriate parameters combinations could result in folds in subsequent forging process. In order to analyze the formation process of the secondary upsetting defect, the finite element model of electric upsetting was constructed based on the multi-field coupling solver platform, MSC. Marc. It is concluded through the numerical simulation with inappropriate parameters combination that the main factor causing the secondary upsetting defect is the large temperature decrease of the deformed portion after the formation of drum-shape in the preliminary stage of electric upsetting. Subsequently, the secondary upsetting defect has been successfully avoided via a three-stage current mode. Finally, a novel optimization method based on close-cycle control of current in numerical simulation was established by developing a current subroutine in MSC.Marc, which was proved to be effective for the elimination of the secondary upsetting defect.

Numerical Solution of an Axisymmetric Eddy Current Model with Current and Voltage Excitations

“…Therefore (21) follows from (30) and (31). Finally, to prove (22) we estimate each term on the right-hand side of (23). Let H ∈ H 2 −1 (Ω), we bound the first term by applying a Poincaré-type inequality…”

“…In particular, this paper is motivated by the study of the electromagnetic behavior of a steel bar submitted to a preforming process called electro-upsetting. This process, which actually requires a multiphysics model [21,22], consists in passing a current through a cylindrical bar which is heated by Joule effect and then to deform it to a particular shape; see, for instance Fig. 1.…”

Design and optimization of multi-stage manufacturing process of stirling engine crankshaft

“…In this study, according to the explanations of the crankshaft design cycles, in the previous chapter and the (5)…”

“…In recent years, significant efforts have been made to develop some new methods including FE method (FEM) and intelligent control system to optimize upsetting process. Quan et al [1] Sukjantha et al [2], Nuasri et al [3], Jeong et al [4], and Quan et al [5] analysed the influence of processing parameters on the upsetting process, predicted an optimum process condition, determined an optimal preform part and saved the secondary upsetting defect, respectively by FEM. Liu et al [6] introduced a new computer-controlled upsetting system and solved the underfill defect in next hot forging.…”

Numerical Analysis of a Six Stage Forging Process for Producing Hollow Flanged Parts from Tubular Blanks

“…Hu et al used multistage upsetting to form a relatively large diameter flange on the end of a pipe [10]. Quan et al also studied the multistage upsetting process [11]. They examined the formation of overlap in the electric upsetting of an engine valve.…”