Study of Surface Modification by Electrical Discharge Machining (1st Report)
Effect of Mixing Powder into Working Fluid for Working Surface
2002 Volume 36 Issue 82 Pages 25-32
Details
2002 Volume 36 Issue 82 Pages 25-32
The purpose of this report is to produce a high-quality surface by electrical discharge machining. In this experiment, a hard layer could be generated on die steels by mixing Ti powder into the working fluid. The layers modified by electrical discharge machining were evaluated based on surface roughness, X-ray residual stress measurement and SEM observation. The insults of the experiment are as follows: 1) A hardened layer was formed by mixing Ti powder into the working fluid. The layer contained TiC and Fe, in which, the Ti content is higher at the part closer to the machined surface. The hardness increases with Ti powder concentration. 2) The residual stress on the working surface by mixing Ti powder into the working fluid was tensile stress. The residual stress was released by heat treatment at temperatures over 600°C. At that time, while the hardness of the surface decreased, the toughness increased.
