Using Long Diameter Verification to Evaluate Antiwear Property of Lubricity

Diameter size of steel ball wear scar is the main basis for judging lubricating oil antiwear properties in the four-ball friction machine test. A new assessment method for antiwear property of lubricity was presented in the paper. First, the wear scar can be detected by convolution operation of gradient filter operator. The scattered noise and morgan chip are removed by moving window denoising. Second, those noise and morgan chippings near wear area are eliminated in measuring direction through using accumulation de-noising. And a new adaptive threshold method is used to measure the long diameter of wear scar in different direction. Finally, lots of sample data of long diameter are checked by normal distribution. The image sample can be used to evaluate antiwear property if long diameter data obeys normal distribution. Otherwise image sample should be obtained by redoing four-ball friction test. Qualitative experiments showed that the extraction of wear scar area was complete and the edges were clear. Data verification is effective for sample selection. The method is simple and has wide applicability.