Diamond vs Cubic Boron Nitride

What this topic covers

Why two superhard materials dominate different machining niches.

Core engineering ideas

Diamond offers exceptional hardness and thermal conductivity.

Cubic boron nitride often performs better for hardened ferrous materials where diamond can suffer chemical wear.

Selection depends on workpiece composition, temperature, desired finish and tool economics.

System tradeoffs

Diamond is not ideal for every material; chemical wear can make cubic boron nitride or conventional carbides better choices in some ferrous applications.

Quality and verification

Tool qualification uses wear, finish, dimensional stability, force and failure-mode evidence rather than hardness alone.

Lifecycle perspective

Refurbishment, retipping and recovery can preserve the value of tool bodies and diamond-bearing material.