Metalworking additives: A new approach to EP properties

Work in the author's laboratory has shown that certain specially designed overbased sulphonate‐compounds function as extreme pressure agents in heavy duty metalworking operations. Depending upon the application, these materials may be used individually or in combination with conventional EP agents; they have also shown a synergism with active sulphur compounds. Film strength tests, controlled tool life evaluations, and field trials confirm that high load‐bearing properties are imparted to metalworking fluid formulations. In addition, we have seen dramatic effects on the quality of machined metal surfaces. As an extremely important benefit, these unconventional extreme pressure agents are environmentally acceptable.