The ability of temperature as a parameter to indicate strain development in sheet metal forming is examined, through the evaluation of thermal generation in the forming of a deep drawn automotive component. In this study temperature was measured by means of a thermographic technique. Three zinc coated materials were examined, namely, delta and zeta phase galvanneal, and hot dip galvanised coated steel. These materials showed varied forming behaviour over a range of blankholder loads and pressing speeds. After forming the strain distribution in the pressing was analysed, and a FE analysis of the process was performed. The measured strains and FE results showed a good correlation. Thermal distributions of the components correlated with the strain distributions. The maximum temperature developed shows an increase with pressing speed. Fracture is shown by a distinct thermal signature. The authors propose that this thermographic analysis technique could be used as a condition monitoring tool to control the sheet metal forming process.
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