Enhancing the sensitivity of a tribological testing method to enable development of lubricants for cold forging

Because of environmental issues, new water-based lubricants are being developed to replace the conventional lubrication approach in cold forging-phosphation plus soap coating. To support the development and application of water-based lubricants, a new testing method that is highly sensitive, accurate, and easy to use was established on the basis of the ring with boss compression test. The dimensions of ring specimens were optimized, and the method's high sensitivity was demonstrated by obtaining scatter calibration curves and determining the distortion of the outer boss. The effectiveness and high sensitivity of the method were experimentally validated using two strategies. The method was then successfully employed to evaluate a commercial water-based lubricant; the effect of lubricant amount and lubrication mode was investigated.