Influence of varying forms of bionic units on repairing remaining quenching surface of gray cast iron

In order to repair and reuse remaining quenching surface (RQS) divided into severely worn surface (SWun-S) and mildly worn surface (MWun-S) of abandoned gray cast iron guide rail, inspired by the bionic theory, varying forms of bionic units such as spot (Sp-S), striation (St-S), and reticulation (Re-S) were fabricated on RQS of gray cast iron through laser processing technology. Firstly, the microstructure, phase composition, and microhardness of bionic units and RQS were analyzed by optical microscopy as well as X-ray diffraction instrument and scanning electron microscopy, respectively. Secondly, the oil lubrication wear experiment was performed on homemade line reciprocating wear machine. The results demonstrated that the bionic units had a significant effect on improving wear resistance of RQS of abandoned guide rail due to the microstructure and higher hardness. In addition, the weight loss ratios of MWun-S, Sp-S, St-S, and Re-S samples were decreased by 36.72%, 36.78%, 62.26%, and 80.39%, respectively, compared with that of SWun-S sample. The mechanism of wear resistance enhancement was also discussed.