Experimental Study on Micro-Grinding of Ceramics for Micro-Structuring

Abstract

In this study, micro-grinding was performed to investigate the machining characteristics of alumina and zirconia. The machining of ceramics remains highly challenging owing to their properties, such as high brittleness and wear resistance, which leads to a shorter tool life and high machining costs. Polycrystalline diamond (PCD) was selected as the tool material, as it is suitable for machining hard and brittle materials, and micro-electrical discharge machining (EDM) was used to fabricate PCD micro-tools. When using a resistor-capacitor generator circuit in micro-EDM, the discharging energy is related to the working capacitance, and by controlling the working capacitance, the different edge radii and the surface roughness of the tool can be easily achieved. The feed rate, depth of cut, and rotation speed were set as experimental parameters to investigate the grinding characteristics of the ceramics. During the experiment, the grinding force and roughness of the bottom surface were monitored, and the roughness of the machined surfaces was measured using a three-dimensional surface profiler. A working capacitance of 1000 pF was used to fabricate a tool with an edge radius of 3.5 µm. The lower radius of the tool edge resulted in a decrease of the cutting force by 50% at most and a surface roughness of 19 nm Ra.

Microfluidic Chip Fabrication of Fused Silica Using Microgrinding

“…Figure 1 shows the experimental setup for the microgrinding process. The system consisted of an X–Y–Z stage, a high-speed spindle, and a dynamometer (9256C2, Kistler Instrumente AG, Winterthur, Switzerland) for measuring the cutting forces [ 10 , 11 ]. As a workpiece material, fused silica was used.…”

“…Polycrystalline diamond (PCD) is an electrically conductive material that can be easily machined via electrical discharge machining (EDM) [ 9 , 10 , 11 ]. Many researchers have used PCD microtools to machine brittle materials.…”

Optimization of Machining Parameters for Milling Zirconia Ceramics by Polycrystalline Diamond Tool

“…However, it is different to machine zirconia ceramics because of their high toughness, high bending strength, high wear resistance and excellent heat insulation which cause severe tool wear and tipping, low surface quality and machining efficiency [ 10 ]. Polycrystalline diamond (PCD) tool has the advantages of high hardness, good thermal conductivity, low friction coefficient and low thermal expansion coefficient, which is an ideal tool for milling zirconia ceramics [ 11 , 12 ]. In recent years, a lot of research about surface quality, tool wear and material removal rate has been done when zirconia ceramics are machined by PCD tool [ 13 , 14 , 15 ].…”