An investigation of tool wear in the dam-bar cutting of integrated circuit packages

Dam-bar cutting is a mechanical trimming process in which the dam-bar between the leads of an integrated circuit (IC) package after post-molding process and deflashing is pieced out. Premature wear of the dam-bar cutting tool leads to higher operating costs and loss of production. In this paper, an investigation has been made to study the effects of punch-die clearance, leadframe materials, tool materials, tool coatings, punch shear and cutting speed on the wear of dam-bar cutting tools. The relationships between the punch flank wear, burr height and the dam-bar cutting force are also explored. Hence, critical factors are determined to optimize the tool life and improve the quality of the dam-bar cutting process.