Why Vacuum Brazing?

Vacuum brazing is a highly effective method for joining diamond tools and is preferred over traditional soldering methods for several reasons. First, vacuum brazing produces high-strength joints that are difficult to wet by materials such as diamonds, PCD, and PCBN. This results in a more secure bond between the diamond and the tool body, leading to increased tool life and durability.

Second, the process of vacuum brazing is very clean and environmentally friendly, as it does not require the use of fluxes or other chemicals. This is particularly important for diamond tools, as the presence of impurities in the soldering process can negatively impact their performance.

Third, the constant and even distribution of temperature across all components during vacuum brazing helps to avoid residual stresses in the components that can result from heating and subsequent cooling. This helps to retain the thermal and mechanical properties of the diamond tool, and can even improve them in some cases.

Finally, vacuum brazing allows for multiple components with multiple brazing points to be joined simultaneously in one brazing process, as all workpieces are exposed to the same brazing temperature due to radiant heat. This increases efficiency and reduces production time, making it a cost-effective option for diamond tool manufacturers.

Technical Data

CPE Power 380V 3P 4 wires or 480V 3P 3 wires
CDA Ø8 mm, 5 ~ 7 kg/cm2
Cooling Water 40 L/min, 19200 BTU/hr
Specification Control System
PLC One touch control integrated 10 programming recipes
HMI 9”
Vacuum Chamber
Quartz Chamber Quartz inner Ø 150 mm
Quartz plate 285 x 140 mm
H75 mm Max
Heating System
Heating Lamp 2 kw x 12 = 24 kw
Heating Rate 800 ℃ /min
Accuracy ±3 ℃
Maximum Operating Temperature 950 ℃
Vacuum System
High Vacuum Pump 1100 L/sec, cold trap, ultra-high vacuum valve
Rotary Pump 670 L/min
Ultimate Vacuum Pressure 20 min < 9x10-6 torr
Pumping Speed 5 min < 5x10-5 torr
Main Frame 1400L x 880W x 1670H mm


  • HMI multilanguage support
  • Datalog collection
  • Remote control and remote access
  • Product traceability

Brazing Procedure


After ultrasonic cleaning, put on paste


Set diamond tip on the shank


Dry the workpiece in the drying oven

Temperature : 100 ℃ ~ 120 ℃
Time : 10~20 min approximately
Atmosphere : Air


Shave extended paste off while necessary


Put into the high speed vacuum brazing machine


Complete brazing

High Speed Vacuum Brazing
vs Conventional Brazing

High Speed Vacuum Brazing Conventional Brazing
Usage Brazing Natural diamond, CVD, PCD, PCBN and related materials on to tool body Some limitations on substrate materials due to thermal coefficient
Brazing Temperature Available up to 900 ℃ Limit up to 750 ℃
Applicable Material
  • PCD, PCBN, tungsten carbide: low temperature brazing
  • PCBN, CVD, CBN, mono crystal diamond, natural diamond: high temperature brazing
Only PCD and PCBN: low temperature
Capacity Around 80pcs per hour, depending on the tool size Max. 20pcs per hour
Brazing Quality Automatic process, consistent quality and complete repeatability Manual process, quality depending on worker’s skill level
Additional Benefit
  • Additional Benefit
  • No need for experienced labor. Operator can perform other jobs while machine is running
  • Lower production cost
  • No dangerous fume inhalation
  • Need flux and extra cleaning
  • Need experienced labor
  • Dangerous fumes
  • No more variables of manual brazing, be free from labors’ skill
  • Guaranteed consistent brazing quality and tip retention
  • Protects PCD/ PCBN/ CVD/ diamonds from oxidation and reduces graphitization
  • 1 Machine = for all types of superabrasive cutting tool products
  • Improves your brazing capacity and quality

Comparison with Induction
or Torch Brazing for ISO Inserts

High Speed Vacuum Brazing Induction or Torch Brazing
Brazing Temperature Available up to 900 ℃ Below 750 ℃
Diamond Type
  • CVD, CBN, mono crystal diamond, natural diamond
Only PCD and PCBN
Brazing Alloy Liquid metal (paste): higher melting point (stable at high temperature machining) Silver alloy : melting point between 600~700 ℃
Capacity 1
(ISO inserts)
40~150pcs per hour depending on the insert size. The smaller the tool, the more you can braze
  • Brazing one by one
  • Manual process
  • 15~20pcs per hour
Capacity 2
(reamers, PCD tipped drills)
10~30pcs per hour depending on size of drill and PCD tip
  • 5pcs max (longer time due to cleaning, sanding, etc)
  • Graphitizes PCD
Flux Cleaning No flux, no need cleaning before and after brazing
  • Cleaning before and after brazing
  • Sanding after brazing
Fixing No need fixing. One time braze due to capillary action Fixing is necessary. Operator must maintain pressure. Possible re-heating necessary

Comparison with Vacuum Furnace
Brazing for ISO Inserts

High Speed Vacuum Brazing Vacuum Furnace Brazing
Cycle time 1.5 hours 8~10 hours
Precision No movement of tips because of rapid heating and cooling Tips are moving at some cases due to long process time

Comparison with Induction Brazing
for Reamers (4 edges and more)

High Speed Vacuum Brazing Induction Brazing
Brazing Speed No difference for more edges Longer time for more edges
Staff 1 entry-level worker can perform other jobs while machine is running At least 1 dedicated experienced worker
Brazing Quality and Yield Rate Automatic process with one simple touch, consistent good quality and yield rate, even for more edges Manual process, quality and yield rate depending on worker’s skill level and will become worse if more edges