Cold forming Research Papers - Academia.edu (original) (raw)

The Knowledge of metal flow and strain at fracture is most importance to the plastic damage in metal forming. Failure in metal working usually occurs as ductile fracture, rarely as brittle fracture. In terms of metal forming, the... more

The Knowledge of metal flow and strain at fracture is most importance to the plastic damage in metal forming. Failure in metal working usually occurs as ductile fracture, rarely as brittle fracture. In terms of metal forming, the propagation of cracks is of little interest, since the main issue is to avoid their initiation. Therefore, the main effort has historically been placed not in developing a full mechanics analysis of ductile cracking, but simply on establishing criteria for predicting the fracture initiation sites and the level of deformation at which the crack will occur. A comparative study has been made on widely used criteria for predicting the occurrence of fracture in metal forming processes by using the upset test data of cylindrical specimens. A simple criterion, which is based on integrals of stress function, is proposed and its applicability is validated through the existing test data on commercial purity aluminium. The finite element analysis results of the complex geometries and loadings can be used in the proposed criterion for predicting the occurrence of defects. The proposed criterion acts as a limiting condition for the defects / cracks initiation under cold working conditions and takes into account the tensile stress ratio and tri-axiality.

Hydroforming is a relatively new metal forming process that offers many advantages over traditional cold forming processes, including the ability to produce more complex components with fewer operations. For certain geometries,... more

Hydroforming is a relatively new metal forming process that offers many advantages over traditional cold forming processes, including the ability to produce more complex components with fewer operations. For certain geometries, hydroforming technology makes it lighter, stiffer, cheaper to manufacture, and requires less blanks, resulting in less material waste. This paper focuses on the analysis of composite T-joints which are used in automobiles under various loads. It is modelled analysed using CATIA V5 and ANYSYS software's respectively. There are several studies on design optimization of automotive T-joints. This paper depicts deformation and stress analysis of T-Joint, when made using sheet hydroforming.