DOI: http://dx.doi.org/10.14741/ijcet/spl.2.2014.25 141 | International Conference on Advances in Mechanical Sciences 2014 Review Article International Journal of Current Engineering and Technology E-ISSN 2277 – 4106, P-ISSN 2347 - 5161 ©2014 INPRESSCO ® , All Rights Reserved Available at http://inpressco.com/category/ijcet Experimental Investigations, Modeling and Simulation of Tailor Welded Blanks : A Review Satya Suresh V.V.N Ȧ* , Srinivasa Prakash Regalla Ȧ , Uday kumar R Ḃ Ȧ Mechanical Department, Birla Institute of Technology and Science-Pilani, Hyderabad Campus, Shameerpet, Hyderabad, India Ḃ Mechanical Department, MGIT, Gandipet, Hyderabad, India Accepted 10 January 2014, Available online 01 February 2014, Special Issue-2, (February 2014) Abstract The present paper summarizes the state of the art developments in numerical modeling and simulation of sheet metal welds commonly known as Tailor welded blanks (TWB). This metal forming process gained lot of importance in recent times due to its vast applications in automotive and aircraft industries. The blanks which consist of different thickness, material and shapes are welded together and forming is carried out. Mechanical and metallurgical properties of weld zone, effect of thickness ratio, material combination and weld line movement were studied in detail. It is noted that very few studies were made towards the experimentation and simulation of TWBs at elevated temperatures. Keywords: Tailor welded blanks, Finite element simulation, Formability, Welding 1. Introduction 1 Sheet Metal welds commonly known as tailor welded blanks or laser welded blanks consists of two or more sheet metals which are welded together with different size, shape and even in thickness also. The blanks may also differ in sense of coating and material properties. The major advantages of employing TWB’s in mass production are weight reduction without loss of rigidity, cost reduction by cutting down the number of dies and punches and structural improvement. The advantages of using TWBs are numerous. They ensure that the components are light, stronger, and provide required functionality at lower costs than parts made from monolithic pressed sheets, as well as improving structural integrity, safety and corrosion resistance in specific areas and they allow greater flexibility in materials selection. The part integration possible with TWB reduces the number of parts and assembly time required per vehicle. However, the disadvantages of TWB are related to the heterogeneous nature of the blank (due to weld and dissimilar materials used), where the thinner / weaker material may deform preferentially and tear prematurely in Stamping, which also results in weld line movement (Saunders and Wagoner, 1994). 1.1 Process parameters of interest Factors that affect formability of TWB can be divided into three categories 1) Material 2) Process and 3) Testing equipment design as shown in table 1 *Corresponding author: Satya Suresh V.V.N The material properties that affect formability include the strain hardening coefficient, and anisotropy. Also, ductility contributes to formability, as it is an indicator of formability. Table 1 Parameters affecting formability Material Process Testing equipment design Sheet thickness Material properties a) Strain hardening coefficient(n) b) Anisotropy (r) Grain size Inclusions Welding Mode of Stretching a) In-plane b) Out-of- plane Strain path a) Bi axial b) Plain strain c) Uni axial Deformation speed Blank holding force Lubrication Draw bead Die corner radius Punch corner radius Punch-die clearance These material properties are obtained through intrinsic tests i.e. uni-axial tensile test. The two material properties that are related to the formability of a material are the n- value and the r- value, where the n-value is the ability of the material to redistribute strain before necking and r- value is the ability of the material to resist thinning during deformation. It should be noted that anisotropy may be introduced by the large deformation inherent in the steel sheet manufacturing process. For example, the initial rolling of the sheet metal will affect further deformation of