Tri-Arc Melt Furnace ABJ-900-3 is identical to our ABJ-900, which is our largest arc melting furnace with a 9″ (229mm) hearth. This furnace is capable of reaching temperatures above 3500°C instantly.

The triple arc option allows for a more uniform melt and for larger batches to be processed without the need to unload and reload. Different materials can also be positioned in the different crucibles and can be melted simultaneously.

The crystal growing option allows up to 4″ (100 mm) crystals to be pulled from a center crucible. The High vacuum system option allows for ultra pure melts when required. All components are operated through an intuitive optional touch panel screen.

Custom cavity shapes are available at no cost, when specified with your order.

Tri-Arc Melt Furnace ABJ-900-3


General specifications:

  • Three copper stingers with tungsten electrode.
  • Operating temperature over 3500ºC.
  • Large Bell Jar hinged loading configuration.
  • Custom copper hearth plate 9.0” dia. (230mm dia.).
  • Sight window with 4″ (102 mm) diameter viewport and separate port with halogen light.
  • Power supply: 500 Amp @ 80% Duty Cycle, 22 kVA.
  • Water cooling safety interlock.
  • Inert gas system with relief valve.
  • Pumping system with roughing pump, vacuum gauge and valve.
  • Optional high vacuum and crystal puller system


The chamber is constructed of stainless steel and electro-polished for good vacuum integrity and appearance. The chamber is double-walled. A water jacket surrounds the chamber and maintains a chamber temperature below 50°C (120F) during normal use. The chamber is rated for high vacuum vacuum to 10-6 Torr (mbar). The chamber is loaded and unloaded by lifting the hinged chamber backwards, which gives complete access to the loading area.

A halogen light is provided to illuminate the chamber internally. The vacuum port is located on the bottom of the chamber, while a 4″ (102 mm) viewport with swinging eye shield is supplied on the front for the user to view the melt area.  Clamps secure the chamber to the base and provide a vacuum tight seal.

A copper hearth plate has cavities to hold melt material. Custom cavity shapes are available at no charge when specified at the time of order.

Electrode stingers

Three copper water-cooled  stingers  with  a replaceable  tungsten  electrode tip provide the means for the arc to melt the samples.  A ball joint allows the stingers to move easily around the chamber. Once positioned, they stay in place without further interaction.  This allows easy melting with multiple stingers for faster and more uniform or continuous melting.

The stinger tip consists of a 0.25” (6.4 mm) diameter Thoriated Tungsten rod, for easy arc starting and longevity.

Vacuum System

A 2 CFM (56 LPM) vacuum pump is standard, which allows the chamber to be evacuated to the 10-2 Torr (mbar) range. A vacuum compound gauge allows chamber pressure to be observed. A back-to-atmosphere valve is provided to air release the system. A diffusion or turbo pumping system is available as an option for pressures in the 10-5 Torr range or below.

Gas System:

This system is designed to operate in a positive inert gas atmosphere of 2PSI ( 0.14 kg/cm sq) above atmosphere. A metering gas valve with flow indicator is supplied to quickly back-fill the chamber to a slightly positive pressure after evacuation and to keep a blanket gas flowing while arc melting. A 2 PSI relief valve will relieve excess gas while maintaining a positive pressure in the chamber. The  30/30 compound gauge (30 PSIG x 30 in. Hg) located on the chamber allows observation of chamber pressure.

Water System:

A water inlet and outlet manifold distributes water to the various water cooled components such as the chamber, chamber base, power cables, hearth plate, etc. The flow circuits are designed to keep all components below 50°C (120F) during operation. A water flow switch is provided to interrupt power in case water flow is interrupted.


Available Options for Arc Melt Furnace ABJ-900-3:

  • Arc casting
  • Powder melting
  • Crystal growing
  • Annealing
  • Metallic buttons
  • Creating alloys
  • Crucible welding
  • Material densification
  • High purity melts
  • Vacuum casting

Arc Melting Furnace ABJ-900-3 General ArrangementArc Melting Furnace ABJ-900-3 with optional gas purifier