Characterization of electroplated diamond wires and the resulting workpiece quality in silicon sawing

摘要

The aim of this research is to introduce a fast characterization method for diamond wires and the resultant silicon workpiece surface quality at high wire cutting speeds. The work is presented in two parts. Initially, four electroplated diamond wires with varying properties are characterized with the proprietary wire analysis algorithm and experimentally investigated at wire speeds up to 75 m/s. Following, the proprietary surface analysis algorithm which evaluates the brittle and ductile material removal characteristics of silicon workpiece surfaces is introduced and experimentally validated. Influence of the wire speed and feed rate on the material removal regime, surface roughness and process forces are studied on the Wire Wrapped Grinding Wheel setup, a novel-design experiment test rig designed to emulate the wire sawing process. The aspects and kinematics of the experiment setup are discussed in detail. Primary findings show that (1) better surface finish is achievable at higher wire speeds with ductile material removal as the dominant material removal mode (2) for wires of different grain sizes, at the cutting speed threshold of around 30 m/s, cutting force behavior changes and the difference between normal forces starts diminishing over this limit.