Diffusion Bonding Vacuum Hot Press

This versatile Diffusion Bonding Hot Press is an integrated system capable of exerting a force up to 200 tons in vacuum or controlled environments at temperatures up to 2400°F on parts heated in an effective hot zone 8" wide x 12" high x 20" long.

Water cooled rams and a cold wall resistance furnace are loacted within the vacuum chamber. External press frame supports chamber, vacuum, and hydraulic pumping systems. Saturable-core reactor power supply with solid state linear power control provides low voltage power to heating elements. Platens up to 8" x 20" in a variety of materials are easily attached to the rams. With the platens removed and the rams withdrawn, the system may be used as a general purpose high-temperature vacuum furnace.

Features

  • Joins material by simultaneous application of heat and pressure.
  • Bonding occurs in solid state eliminating need for melting materials or melting point metal filler.
  • Can be used as a general purpose high-temperature vacuum furnace.
3520 Series full view

Specifications

ChamberHorizontal, 30" diameter x 30" long stainless steel interior 100% jacketed with full-opening, hinged door with clamps, supported by press frame @53"CL elevation. Ports for power, rams, thermocouples, two 2 1/2" shuttered sight glasses, vacuum pumping and inert gas purge.
Press & FrameHydraulic press, double-acting with frame-mounted 3 stage hydraulic power unit with force/pressure regulator, advance, hold and reversing valve. Pressure gauges and relief valve. Pedestal and hydraulic rams are water-cooled, may be withdrawn to clear furnace for general use. Stroke 6 5/8".
Vacuum & Inert Gas System10" main valve air-operated failsafe closing; 10" 4300 l/sec. diffusion pump; multi-coolant chevron baffle; 50 CFM mechanical pump; 3.5 CFM holding pump; welded steel manifolding and vibration isolation, 3" manual roughing and fore valves; connections for gauges and leak detector; vacuum gauge control combination hot filament ionization and two-station thermocouple, 1 to 1000 microns and 1 micron to 2 x 10-7 torr. Inert atmosphere system includes 5 psig relief valve, 30"-0-15 psig Bourdon gauge, needle valve for gas inlet. Electrics include circuit breakers, pilot lamps, semiautomatic vacuum pump system controller, complete with function selector switch and keylock overrides mounted in NEMA-1 control cubicle.
Internal MechanismFurnace cold wall, refractory metal rod elements and inner heat shields. 6" diameter water-cooled ram shanks, 12&qot; daylight when full open without platens attached which act through 6" diameter sliding seals.
Power Supply75 kva, three-phase saturable core reactor with solid state linear power control. Includes furnace volt and current meters, cooling water flow interlock, shunt trip circuit breaker.
Temperature Controls (Optional)3-mode proportioning control with adjustable set point and strip chart recorder with Pt/Pt-10% Rh thermocouple. Separate indicating over-temperature indicator coutout with thermocouple.
Space & Service Requirements
Floor9' wide x 9' deep x 9' high.
Power440 volts, 3 phase, 60 hertz, 125 amps.
Water12 gpm @ 40 to 50 psig 80°F maximum with individual circuit valves.
DrainOpen to 3" diameter.
Air2 CFM @ 100 psig.
Inert Gas16 ft3 STP per backfill @ 20 to 30 psig.
Performance
Temperature2400°F maximum uniformity ±25°F empty.
Vacuum1 x 10-5 torr in 40 minutes - 10-6 torr range ultimate.
Maximum press force200 tons.

Applications

Materials may be joined by the simultaneous application of heat and pressure for a prescribed time in a high vacuum or inert atmosphere. The bonding occurs in the solid state, thereby eliminating the need for melting the materials as in welding, or the introduction of a lower melting point metal filler, as in brazing. Distortion and localized stresses are minimized and inaccessible surfaces can be successfully joined. Varying section thicknesses may be bonded to achieve a non heat affected zone surrounding the junction. Due to the vacuum environment, atmosphere senstive material can be processed without encapsulation. High vacuum cleans the surfaces to be bonded and assures high integrity joints.