Microstructure and Properties of CBN Abrasive Blocks with Cu-Sn-Ti Binder Modified by Ceramic Glass Powder

Area of Science:

• Materials Science
• Mechanical Engineering
• Tribology

Background:

• Cu-Sn-Ti metallic-bonded Cubic Boron Nitride (CBN) abrasives are crucial for superhard material grinding.
• High density and toughness of these abrasives limit grain protrusion and self-sharpening.
• Modification of the binder is needed to overcome these limitations.

Purpose of the Study:

• To fabricate composite-bonded CBN abrasive blocks with improved self-sharpening performance.
• To investigate the effect of ceramic glass powder addition on the properties of Cu-Sn-Ti binders and CBN abrasive blocks.
• To determine the optimal glass powder content for enhanced abrasive performance.

Main Methods:

• Incorporation of ceramic glass powder into Cu-Sn-Ti binder.
• Fabrication of composite-bonded CBN abrasive blocks.
• Measurement of flexural strength, binder microhardness, and microstructural characterization.
• X-ray diffraction (XRD) for phase analysis and tribological tests against silicon nitride.

Main Results:

• Glass powder addition decreased flexural strength (32.5-89.4%) and binder microhardness (26.5-58.3%).
• New interfacial phases (Ti2O3, Ti5Si3, Ti(Cu,Al)2) formed at high temperatures, improving bonding.
• Micropores formed in binders, altering CBN abrasive fracture mode and enhancing self-sharpening.
• Overall wear resistance declined, but the No.3 sample (8.33 wt% glass powder) showed optimal performance.

Conclusions:

• Ceramic glass powder effectively modifies Cu-Sn-Ti binders for composite-bonded CBN abrasives.
• The addition creates favorable interfacial bonding and enhances self-sharpening despite reduced strength.
• A glass powder content of 8.33 wt% yields the best balance of properties for precision grinding.