Vacuum Brazing of CBN Tools

Vacuum brazing is a highly advanced joining process used in the manufacture of CBN (Cubic Boron Nitride) cutting tools, which are designed for machining hardened steels and high-wear materials. Due to the extreme hardness and thermal stability of CBN, conventional joining methods are not suitable, making vacuum brazing the preferred technique for producing reliable and high-performance tools.

In this process, CBN tips are bonded to tool bodies—typically made of tool steel or tungsten steel—inside a high-temperature vacuum brazing furnace. The oxygen-free vacuum environment prevents oxidation and ensures excellent wetting of the brazing alloy. Specially selected brazing filler metals are used to create a strong metallurgical bond without damaging the CBN cutting edge.

Vacuum brazing minimizes thermal stress and distortion, preserving the sharpness and integrity of the CBN material. The resulting tools exhibit exceptional wear resistance, high bonding strength, and excellent thermal stability, enabling high-speed and precision machining with extended tool life.

Because of these advantages, vacuum brazed CBN tools are widely used in automotive, aerospace, die and mold manufacturing, and precision machining industries, where consistent performance and durability are essential.