Nanoengineered Polycrystalline Diamond Composites with Advanced Wear Resistance and Thermal Stability

Area of Science:

• Materials Science
• Nanotechnology
• Tribology

Background:

• Polycrystalline diamond composites (PDCs) are crucial for drilling tools.
• Current PDCs often use metallic cobalt binders, limiting thermal stability and wear resistance.
• Nanoengineering diamond surfaces offers a route to improved composite properties.

Purpose of the Study:

• To synthesize novel polycrystalline diamond composites (PDCs) using fluorinated diamond feedstock.
• To investigate the interfacial chemistry and binding phases in these new PDCs.
• To evaluate the thermal stability and wear resistance of the developed PDCs.

Main Methods:

• Utilizing fluorinated micrometer-sized diamonds coated with nanodiamond particles as feedstock.
• Employing two synthesis methods: (i) Co infiltration into a fluorinated diamond layer with Al, and (ii) sintering of homogeneous fluorinated diamond mixtures with Al and Co.
• Characterizing the binding phase using advanced analytical techniques.

Main Results:

• The binding phase in the new composites consists of intermetallic AlCo or ternary carbide AlCo3C, unlike commercial PDCs.
• Composites from homogeneous mixtures demonstrated improved thermal stability.
• Two-layer experimental composites exhibited over two times higher wear resistance than leached commercial PDCs in granite turning tests.

Conclusions:

• Nanoengineering fluorinated diamond feedstock enables the creation of advanced PDCs with unique binding phases.
• The developed PDCs offer superior thermal stability and wear resistance compared to conventional materials.
• These findings suggest significant potential for these novel PDCs in demanding applications like drilling and cutting tools.