Papers by Keyword: Shaving

Abstract: This study investigated the effects of the die clearance on the shearing and shaving processes of the stainless steel (SUS316LVM) wire at micro scale. A die set was developed and installed on a precession press equipped with a load cell and a displacement sensor to conduct experiments. By using different punches in the same die set, the specimens prepared from 316LVM stainless steel wires with 0.5 mm diameter were first sheared and then shaved. Experimental results show that the burnished area of the sheared edge increases with the reduction of the clearance between the punch and die in the shearing process. The clearance also significantly affects the load curves. Moreover, the shaving process does increase the burnished area on the shaved edge of the specimen. By an appropriate feed in the shaving process, it is possible to trim the extra material from the sheared edge that results in a nearly complete burnished surface on the shaved edge of the stainless steel wire. This research provides a basis for understanding of the die clearance effect on the shearing and shaving processes at micro scale.

Abstract: Shaving is one of the precision shearing methods used to remove the rollover and fractured surface. The rollover and fractured surface formed in the punching stage are removed by shaving. It is expected that the rollover will be reduced when half punching with a negative clearance is carried out in the punching stage. In this study, the influence of the punch penetration depth in the punching stage on the cut edge after shaving was investigated. The results of this study clarified the followings: When the punch penetration depth in the punching stage with negative clearance is large, the sheared surface obtained by shaving after half punching with negative clearance is larger than that obtained by conventional punching. The sheared surface obtained by shaving after half punching with negative clearance increased with increasing the punch penetration depth in the punching stage with a negative clearance. The rollover produced by shaving after half punching with negative clearance is smaller than that produced by conventional shaving. In addition, the chip produced by shaving after half punching is connected to the sheet material under the punch. From the observed deformation of the chip produced in the shaving stage after half punching with negative clearance, the mechanism of shaving after half punching is considered to be cutting followed by shearing.

Abstract: Burrs are unwanted materials remaining not only after the machining operation but also after the sheet metal cutting operation. Burr formations decrease the part accuracy and increase the cost for the deburring operation. In this study, the reciprocating shaving process was proposed to eliminate crack and burr formations in the pressed parts. The finite element method (FEM) was used as a tool to investigate the possibility of this process and its working process parameters as well. The FEM simulation results showed the effects of clearance in shearing operation, shaving allowance, and half-shaving direction on the shaved surface. These results were validated by laboratory experiments, and they showed a good agreement with each other. The FEM simulation could be used as a tool for prediction of the cut surface in the reciprocating shaving process. The results revealed that the reciprocating shaving process could be applied for eliminating crack and burr formations in pressed parts using suitable working process parameters.