Research on quality improvement of the cross section cut by abrasive water jet based on secondary cutting

Abstract

The cross section after abrasive water jet cutting can be roughly divided into several parts including initial zone, smooth zone, and rough zone. The surface quality of the smooth zone is high. But, the surface quality of the rough zone is very low due to the existence of striations. In addition to striations, the kerf taper is also a major defect of abrasive water jet. The defects of cutting quality greatly limit the application range and the further development of abrasive water jet machining technology. In order to improve the cross section quality of abrasive water jet cutting, four secondary cutting schemes including the positive secondary cutting, the opposite secondary cutting, the reversed positive secondary cutting, and the reversed opposite secondary cutting were proposed on the premise of not increasing cutting power (i.e., parameters such as pressure, abrasive flow rate, and abrasive particle properties remain unchanged). The cross section after secondary cutting and the cross section after single cutting were compared. The contrast results show that the opposite secondary cutting scheme is better than other methods. The secondary cutting doubles the processing time, while as we know, if the traverse speed is reduced by half, it can also increase the cutting quality at the expense of doubling the processing time. Therefore, the cross section after secondary cutting and the cross section after half-traverse-speed cutting were compared. The contrast results show that the opposite secondary cutting scheme is also more feasible than the half-traverse-speed cutting scheme.