Agus Dwi Anggono

Finite Element Simulation of the Drawability of Tailor-Welded Blank

Tailored welded blank (TWB) consists of steel sheets of different thicknesses and strength which welded into one sheet to reduce weight and production costs, to increase dimensional accuracy and strength. Since a tailored blank is composed of different sheets of metals having different thicknesses and properties, the forming of tailored blanks then creates a lot of technical problems especially in the scheme of deformation. The objective of this work was to evaluate the drawability of tailored blanks. In order to assess the forming behavior of the tailor-welded blanks under the influence of weld orientations, a finite element and experimental methods were conducted. Three welded specimens with weld lines oriented at an angle of 0°, 90° and 45° with respect to the direction of load were investigated. The finite element result showed in a good agreement with the experimental result. The result of the experiment showed that a welded part was characterized by a higher strength and lower plasticity compared to those of the base material. Hence, the weld influences the strain distribution of the tailor-welded specimens. This phenomenon depends strongly on the direction of the weld against the direction of tensile load. The lowest strains occur in the specimen with a longitudinal weld.

An Alternate Method to Springback Compensation for Sheet Metal Forming

The aim of this work is to improve the accuracy of cold stamping product by accommodating springback. This is a numerical approach to improve the accuracy of springback analysis and die compensation process combining the displacement adjustment (DA) method and the spring forward (SF) algorithm. This alternate hybrid method (HM) is conducted by firstly employing DA method followed by the SF method instead of either DA or SF method individually. The springback shape and the target part are used to optimize the die surfaces compensating springback. The hybrid method (HM) algorithm has been coded in Fortran and tested in two- and three-dimensional models. By implementing the HM, the springback error can be decreased and the dimensional deviation falls in the predefined tolerance range.

Simulation of Ironing Process for Earring Reduction in Sheet Metal Forming

Manufacturing of beverage cans is porcessed by using multi-stage ironing following deep drawing from the sheet material of aluminum and steel. An earing profiles are develops during deep drawing of cylindrical cup due to the planar anisotropic properties of sheet. Therefore, the analysis of earing is important to evaluate and control the development of earing. This paper describes a simulation of the cold ironing process in the forming cylinder cap. The ironing process in this study was focused on the prediction of height increasing, earing and thinning. Two different materials of aluminum AA5042 and AKDQ steel were selected for comparison. The results show that the increasing of cup height was in the same trend.

Effect of Ni underlayer thickness on the hardness and specific wear rate of Cu in the laminated Ni/Cu coatings produced by electroplating

In this work, the effect of the Ni underlayer with different thicknesses on the mechanical properties of Cu surface was studied. A laminated structure of Ni/Cu layer was prepared using electroplating on carbon steel substrates. The nickel layer was firstly plated on the steel using a current voltage of 2.3 V and varied plating times using 30, 60, 90, 120 and 150 minutes. The copper layer was subsequently electroplated on the nickel surface using a fixed current voltage of 1.9 V and plating time of 30 minutes. The result showed that XRD pattern observed on the surface of Ni/Cu coating indicates the formation of Cu single phase instead of Ni/Cu alloy. Application of plating time variations on the Ni underlayer using 30, 60, 90, 120 and 150 minutes produced an average thickness of Ni underlayer with 19.9, 48.4, 50.1, 62.1 and 64.9 µm, respectively. The thickness of Cu as the outer layer for different thickness of Ni was kept constant at approximately 23.66 µm. The hardness measurement on the Cu underlayed by Ni deposited using different plating times indicated that the hardness of Cu was 91.63, 93.20, 97.93, 102.60 and 106.1 HV, respectively. Whereas, the specific wear rates of Cu were 6.59 × 10−6, 6.11 × 10−6, 5.99 × 10−6, 3.63 × 10−6 and 3.55 × 10−6 mm3/kg.m, respectively. The present study showed that the mechanical properties of Cu layer surface with a fixed layer thickness were influenced by the application Ni underlayer with different thicknesses. An increase of Ni underlayer thickness has increased the hardness and specific wear rate of the Cu layer.In this work, the effect of the Ni underlayer with different thicknesses on the mechanical properties of Cu surface was studied. A laminated structure of Ni/Cu layer was prepared using electroplating on carbon steel substrates. The nickel layer was firstly plated on the steel using a current voltage of 2.3 V and varied plating times using 30, 60, 90, 120 and 150 minutes. The copper layer was subsequently electroplated on the nickel surface using a fixed current voltage of 1.9 V and plating time of 30 minutes. The result showed that XRD pattern observed on the surface of Ni/Cu coating indicates the formation of Cu single phase instead of Ni/Cu alloy. Application of plating time variations on the Ni underlayer using 30, 60, 90, 120 and 150 minutes produced an average thickness of Ni underlayer with 19.9, 48.4, 50.1, 62.1 and 64.9 µm, respectively. The thickness of Cu as the outer layer for different thickness of Ni was kept constant at approximately 23.66 µm. The hardness measurement on the Cu underlayed by...

Influence of tool rotation and welding speed on the friction stir welding of AA 1100 and AA 6061-T6

Dissimilar welding of aluminum is an innovation used to increase the effectiveness and efficiency in making a product or component. It has been applied on the automotive industry, aerospace, and sh...

Springback Prediction Compensation and Optimization for Front Side Member in Sheet Metal Forming Using FEM Simulation

Numerical simulation by finite element method has become a powerful tool in predicting and preventing the unwanted effects of sheet metals technological processing. One of the most important problems in sheet metal forming is the compensation of springback. To improve the accuracy of the formed parts, the die surfaces are required to be optimized so that after springback the geometry falls at the expected shape. This paper presents and discusses numerical simulation procedure of die compensation by using the methods of Simplified Displacement Adjustment (SDA). This analysis use Benchmark 3 models of Numisheet 2011. Sensitively analysis was done by using finite element method (FEM) show that the springback values are influenced by element size, integration points and material properties.

Hybrid Die Compensation Method to Accommodate Springback Error in Sheet Metal

Springback phenomenon theoretically occurs for anything kind of deep drawing or sheet metal forming process. In the real manufacture, it is a well known and avoided characteristic of every process that involves plastic deformations on elastic metals. To improve the accuracy of the formed parts, the die surfaces are required to be optimized and compensate therefore after springback the geometry falls at the expected shape. The proposed procedure combined two methods of die compensation; Displacement Adjustment Method (DAM) and Spring‐forward method (SFM) of Karafillis and Boyce (K&B) called Hybrid Method (HM). Both are based on iteratively comparing the deformed shape with the target. According to the advantages of each method DA and K&B to solve the springback compensation problem, these methods are applied alternately. This paper presents and discusses the proposed framework in accommodating springback in sheet metal forming.