Experimental Study On Fine Blanking Process For Halogen-free PCB

Halogen-Free Print circuit board (HF-PCB) categorized as low-pollution and high stability iswidely used in electric industry for hard disk, computer main bord and so on. HF-PCB has specialrequirement for shearing process: debonding namely the length of honrizontal crack must be shorterthan the thickness of the HF-PCB, further more, matrix crack namely vertical crack is forbidden tooccur according to IPC standard.So far, HF-PCB is sheared by laser or CNC milling machine, however, the cost of laser plant isvery high while the efficency of CNC milling machine is very low. This paper introduces thedesigning of the fine blanking die of which the counter press is supported by rubber and pneumaticcylinder and resist the crack propagation according to the theory of fine blanking, carry out theexperiment in the single action hydraulic stamping press with the help of counter press system,finally make microsectioning of HF-PCB after fine blanking in order to inspect whether the shearingeffecf is qualified or not.The research result indicates:1.Except for some locations with small radius, Fine blanking forHF-PCB can resist the crack propagation, especially horizontal crack.2.Increase the ability ofanti-eccentrically load for fine blanking die by adopting floating structure and double guiding pin.3.Carry out the fine blanking procedure for HF PCB with normal hydro press by using rubber andpneumatic system.