Wear mechanism of metal bond diamond wheels trued by wire electrical discharge machining

• Published in: Wear Vol. 252; no. 7; pp. 644 - 653
• Main Authors: Rhoney, Brian K., Shih, Albert J., Scattergood, Ronald O., Ott, Ronald, McSpadden, Samuel B.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.04.2002; Amsterdam Elsevier Science; New York, NY
• Subjects: Applied sciences; Building materials. Ceramics. Glasses; Ceramic industries; Chemical industry and chemicals; Diamond wheels; Electrical discharge machining (EDM); Exact sciences and technology; Friction, wear, lubrication; General studies; Grinding wheel wear; Machine components; Mechanical engineering. Machine design; Scanning electron microscopy (SEM); Technical ceramics; Diamond wheels; Grinding wheel wear; Scanning electron microscopy (SEM); Electrical discharge machining (EDM); Scanning electron microscopy; Grinding wheel dressing; Diamond tool; Machining; Experimental study; Grinding; Electrical discharge machining; Scanning microscope; Tool wear; Cutting tool; Stereogram; Stereopsis; Ceramic materials
• ISSN: 0043-1648; 1873-2577
• DOI: 10.1016/S0043-1648(02)00019-4

The stereographic scanning electron microscopy (SEM) imaging was used to investigate the wear mechanism in wire electrical discharge machining (EDM) truing of metal bond diamond wheels for ceramic grinding. A piece of the grinding wheel was removed after truing and grinding to enable the examination of wheel surface and measurement of diamond protrusion heights using a SEM and stereographic imaging software. The stereographic SEM imaging method was calibrated by comparing with the profilometer measurement results. On the wheel surface after wire EDM truing and before grinding, some diamond grain protruding heights were measured in the 32 μm level. Comparing to the 54 μm average size of the diamond grain, this indicated that over half of the diamond was exposed. During the wire EDM process, electrical sparks occur between the metal bond and EDM wire, which leaves the diamond protruded in the gap between the wire electrode and wheel. These protruding diamond grains with weak bond to the wheel were fractured under a light grinding condition. After heavy grinding, the diamond protrusion heights were estimated in the 5–15 μm range above the wear flat. A cavity created by grinding debris erosion wear of the wheel bond could be identified around the diamond grain.