Our bottom loading sintering furnace is tailored for high temperature sintering of electronic components. Cycles consist of atmosphere preparation, heating, forced cooling and controlled oxidation. This furnace has a usable zone of 12” diameter x 22” high (305mm x 559 mm), and is suited for large batch processing.

This furnace features two chambers, a bottom chamber for loading and unloading, cooling and controlled oxidation, and the top chamber for high temperature sintering. Both chambers atmospheres are isolated, an electric lift moves the load stack from the bottom chamber into the heating chamber.

The hot zone is capable of temperatures up to 2100°C with Tantalum or Tungsten hot zones.

A high throughput 10″ or 16″ diffusion pumping system handles load out-gassing typically seen during product heat-up.

An intuitive customized HMI interface runs completely automated cycles start to finish.

Refer to our other sintering furnace models for higher throughput models, able to process multiple batches simultaneously.

Bottom Loading Sintering Furnace

Specifications

General specifications:

  • Hot zone Size 12” diameter x 22” high (305 mm x 559 mm)
  • Tantalum or tungsten heating zone (other materials available)
  • 2100°C (3812 °F) maximum temperature
  • +/- 10°C temperature gradient across usable zone
  • Bottom chamber for loading and cooling, top chamber for sintering.
  • Controlled oxidation at end of cycle
  • High capacity diffusion pumping system 10″ or 16″
  • Gas heat exchanger for rapid load cooling
  • Electric load lift for precise load movement
  • Fully automated cycles with computer interface
Details

Bottom Chamber

This chamber is manufactured from stainless steel, is double-walled, water-cooled and electro-polished. The chamber door is hinged for quick, easy and full access to the loading area. Quick-acting clamps are provided to secure the door and ease of access to the load.

The bottom chamber has three functions: Load and unload area, Cooling chamber and Controlled Oxidation chamber.

The recirculating gas heat exchanger allows for a quick cool-down to room temperature.

Several sensors, valves and switches are present on this chamber for operation and safety.

Top Chamber

The furnace hot chamber is fabricated in two sections consisting of an upper and lower chamber. The upper chamber section contains the power connections for the heater while the bottom chamber section contains the pumping port. This design allows for easy access and maintenance of the hot zone with minimal disassembly. Both chamber sections are double-walled, water-cooled and are manufactured from stainless steel. The hot zone accommodates a work stack that is up to 7″ in diameter and 12″ high.

Heating element and shielding are available in Tantalum, Tungsten or Molybdenum. The heating element is a panel or mesh heater with excellent uniformity, longevity and high watt density for fast ramp rates. Surrounding the heater are several layers of heat shielding to minimize heat losses and provide excellent uniformity.

On top of the chamber is a dished cover with several ports to accommodate temperature and vacuum sensors. A sight window offset from the center of the heat zone centerline is used for optical temperature measurement.

Part trays rest on a hearth plate, supported by hearth pins. A center pin with a clevis connection on the top extends through all of the trays; the base plate contains heat shields that protect the plate from heat radiation. This entire assembly is lifted from the system when loading or unloading.

Load Lift and Isolation Valve

A load lift for the load arm acts as both a transfer mechanism and vacuum seal between the top and bottom chamber.

An electric linear actuator provides vertical movement of the load from the bottom chamber into the top chamber. The load arm base plate is tapered and provides a vacuum seal between the top and bottom chamber when the load arm is in the up position. Travel distance, speed and acceleration are preset to provide smooth accurate and repeatable load motion.

When the load is in the bottom chamber, an isolation valve closes to seal off the top chamber. The top chamber remains under constant vacuum, while the bottom chamber can be under vacuum, or be backfilled with air or inert gas.

Power Supply

The heater power supply is a 100 kVA three phase SCR-controlled transformer package housed in the power supply & instrumentation enclosure. The transformer is sized with extra power for fast ramp rates and has two secondary voltage taps on the transformer, one for new elements and one to match the changing characteristics of an aging element, this allows for extended life. All protective and safety devices are incorporated, meeting all applicable NFPA standards.

Control System

Our batch sintering furnaces feature intuitive HMI software to fully automate the batch cycles from start to finish with minimal operator interaction.

Batch IDs or part numbers are scanned in or entered before a run, looked up in a central database and a corresponding recipe is loaded containing all parameters to run a specific heat, cool down and  controlled oxidation profile. When a run is complete, a beacon will alert the operator.

The software features overview screens, alarming, trending, user security, recipe management, data logging, and a manual operation mode for testing and maintenance. Furnace configuration settings are accessible by administrators.

Vacuum System

A 10″ or 16″ ASA high throughput vacuum pumping system is capable of pumping the furnace chamber down to the 10-6 Torr (Mbar) range.

This pumping system consists of a 350 CFM roughing pump with blower, a 10″ or 16″ diffusion pump, water-cooled pumping elbow, and roughing, foreline and high vacuum valves. A holding pump and holding valve are provided to back up the diffusion pump when the roughing pump is in use. Multiple vacuum sensors and limit switches tie directly into the PLC to control the vacuum system.

A 10″ or 16″ cold trap on top of the diffusion pump is cooled with an ozone-friendly refrigeration chiller. This cold trap prevents diffusion pump oil vapor from back-streaming into the chamber and  allows a lower ultimate vacuum level.

An optional turbo pumping system is available to obtain a vacuum level of 10-7 to 10-8 Torr range.

Gas System

This furnace system was designed to operate in a vacuum or inert gas (Argon) environment. The maximum positive operational pressure in this system is 1 PSIG (1082 mbar). The hot chamber and cooling chamber both have a pressure switch to monitor and control the chamber gas pressures.

A relief valve and a compound gauge are installed on each chamber.

Water Cooling System

The furnace water-cooling system consists of an inlet and outlet manifold to distribute water effectively throughout the furnace components. Each water circuit can be regulated by independent manual ball valves to maximize cooling efficiency. A water flow interlock protects the furnace in the event of a water flow failure. Power to the hot zone and other water cooled components is turned off if water flow is below recommended minimum for a certain amount of time.

Utilities

Power:up to 150 kVA based on configuration, 380-480-575 V/3/50-60 Hz
Water:up to 26 G.P.M. (100 lpm) based on kVA @ 70°F (20 °C) and 50 P.S.I.G. (3.4 bar)
Process Gas:Argon or nitrogen, 100 lpm @ 50 P.S.I.G. (3.4 bar)
Compressed Air:60-90 P.S.I.G. (4.1 – 6.2 bar) filtered

Options

Available Options:

Applications
  • Annealing
  • Brazing
  • Ceramic firing
  • Degassing
  • Hardening
  • Heat Treating
  • Metallic alloying
  • Metal Injection Molding (MIM)
  • Nitriding
  • Sintering
  • Stress-relieving
Drawings

Coming Soon!

Product Catalog

View our complete searchable Product Catalog