Etching of the Ceramic Surface by Electric Discharge Method in Electrolyte Solution

Abstract

An experimental investigation of the etching of the surface of ceramic materials was carried out by means of electric dischage machning method.
It was conformed that the surface of ceramic materals may be etched in electrolyte solution by superposing the effect of electric discharge, and that the solutions thus activated attack the grain boundary and the grain itself with the different rate of erosion owing to the different energy levels.
Test were carried out using sintered alumina, petalite, cermet (cobalt-bonded tungsten carbides), barium titanate and ferrite (nickel system) as samples.
It was observed that 1) the sintered alumina in 33% HaOH solution or 20% HF solution, 2) the petalite in 25% NaOH solution or 35% HCl solution, 3) the cermet in 20% HF solution, 4) the barium titanate in 25% NaOH solution, 5) the ferrite in 25% NaOH solution gave the good results.