Application of Calcium Carbonate as Green Lubricant Additive in Sheet Metal Forming

The application of calcium carbonate particles as a green lubricant additive for sheet metal forming processes has been evaluated. Different particle sizes were tested, along with different concentrations of particles in a lubricant that typically does not perform well by itself. The lubricant mixtures were tested under pin-on-disc, four-ball, and bending-under-tension test conditions.

The results of the different tribological tests were compared to determine whether standard tests, such as the four-ball test, could predict lubricant performance under sheet metal forming conditions. The application of any concentration of particles was shown to be beneficial to the lubricant performance in terms of wear resistance even though friction increased when calcium carbonate particles were added to the base paraffin oil.

Small particles (40 nm) exhibited better performance than large particles (2 μm).