Wear Behaviors of Nanocrystallization Surface of Q235 Steel by High Energy Peening

By means of high energy peening (HEP), nanocrystallization surface was prepared on the Q235 steel. The friction and wear behaviors of HEP, polished HEP and original samples in dry or lubricating sliding were investigated by a pin-on-disc tester. The results showed that nanocrystallization surface was generated and many pits were formed. The wear loss of HEP samples with / without polishing are both higher than that of original one in dry sliding. In liquid paraffin (LP), the wear loss of HEP sample became lower for the pits in favor of keeping lubricant oil, and the frictional coefficients of the three samples were all close to 0.1. With the high chemical activity of nanocrystallization surface, the wear resistance of HEP samples with / without polishing got a remarkable increase than that of original one when ZDDP was added into LP. The wear resistance of HEP sample at the load of 35N was 1.63 and 1.26 times as that of original and polished samples.