FINE GRAIN AND AMORPHOUS SURFACES BY ELECTRO-SPARK ALLOYING

THE PROPOSED STUDY WILL RESEARCH AND DEVELOP A UNIQUE TYPE OF SURFACE ALLOYING PROCESS IN WHICH THE CONTACT TIP OF A SCANNING ELECTRODE IS TRANSFERRED TO AND ALLOYED WITH AN ELECTRICALLY CONDUCTING SUBSTRATE MATERIAL BY THE PASSAGE OFREPETITIVE, HIGH CURRENT, AND SHORT DURATION ELECTRICAL PULSES. THE DEPTH OF THE TREATED SURFACE IS CONTROLLED BY THE PULSE PARAMETERS AND THE SCANNING RATE OF THE ELECTRODE,THUS THE COMPOSITION OF THE SURFACE LAYER CAN BE VARIED FROMTHAT APPROACHING THE SUBSTRATE TO THAT APPROACHING THE ELECTRODE. IN PHASE I, THE ALLOYED PHASES AND COMPOSITION AT DIFFERENT THICKNESSES ASSOCIATED WITH PULSE DURATION AND ENERGY LEVEL WILL BE DETERMINED FOR CERTAIN PURE METAL AND CARBIDE ELECTRODES APPLIED TO A TITANIUM ALLOY SURFACE. THEFORMATION OF FINE GRAINED AND POSSIBLY AMORPHOUS PHASES FORMED THROUGH THE SECTIONS WILL BE INVESTIGATED AND COMPARED TO HARDNESS AND WEAR RESISTANCE. THIS WILL ESTABLISH A BASIS FOR PHASE II WHICH WILL EXTEND THE WORK TOVERY HIGH AND VERY LOW PULSE LEVELS AND LEAD TO PROCESS OPTIMIZATION SPECIFICATIONS AND IDENTIFICATION OF COMMERCIALAPPLICATION OPPORTUNITIES OF THE ELECTRO-SPARK ALLOYING (ESA) PROCESS.