Abstract
Hot forging is a manufacturing method that is applied to a wide variety of highstrength automotive components. The prediction of die life in hot forging is vital to satisfy demands for cost reduction by shortening production preparation times and designing longer life dies. Around 70% of die failures that occur in hot forging processes result from wear related to increases in die temperature. Therefore, a system has been developed to predict die life by using CAE at the product and hot forging process design stages to calculate die temperature and wear.
During the hot forging process, lubricant is applied to the die to facilitate release of the blank, and to prevent seizure and wear. The chosen method for spraying lubricant can change cooling properties, affecting die temperature increase and thus the progression of die softening. The cooling properties of lubricant spraying must be quantified before the amount of die wear can be predicted with high precision.
This article describes a combination of experiments and CAE for quantifying the cooling properties of lubricant application with jet and spray based on the heat transfer coefficient. The article also presents details of a database of cooling properties that has been created and built into the CAE system, enabling analysis of die cooling and wear for any hot-forged part.
Keywords: hot forging, CAE, die life, wear, lubrication, heat transfer coefficient