Study of the EDM Process of Bimetallic Materials Using a Composite Electrode Tool

Area of Science:

• Materials Science
• Manufacturing Engineering
• Surface Engineering

Background:

• Bimetal profile products leverage combined material properties like strength and corrosion resistance.
• Electrophysical processing, specifically electrical discharge machining (EDM), is crucial for manufacturing these advanced materials.
• Optimizing EDM for bimetallic materials presents unique challenges due to material heterogeneity.

Purpose of the Study:

• To enhance the efficiency and accuracy of electrical discharge machining (EDM) for bimetallic products.
• To investigate the impact of electrode-tool (ET) materials with varying physical and mechanical properties on the EDM process.
• To develop a theoretical model for predicting material removal in steel-copper bimetals during EDM.

Main Methods:

• Utilized a steel backing (09G2S) with an M1 copper surfacing for bimetallic workpiece preparation.
• Employed an Electronica Smart CNC copy-piercing EDM machine for material processing.
• Tested graphite, copper, and composite electrode-tool (ET) materials.

Main Results:

• A theoretical model was developed to calculate bimetallic material removal based on EDM parameters and ET material.
• Processing the steel layer resulted in microcracks along grain boundaries, irrespective of the ET material.
• Processing the copper layer led to the formation of enlarged holes.

Conclusions:

• The choice of electrode-tool material significantly influences the EDM process outcomes for bimetallic steel-copper components.
• Understanding the distinct material removal mechanisms in steel and copper layers is critical for process optimization.
• Further research can refine EDM strategies for improved surface integrity and dimensional accuracy in bimetal processing.