Soldering Fiber Optic for Hermetic Sealing

Solderingย Fiber Opticย Cable for Hermetic Sealing With IGBT Induction Soldering Heater

Objective To heat a Kovar ferrule and fiber optic cable to 297ยฐF within 10ย seconds for a soldering application, to form a hermetic seal
Material Gold-coated cable, Kovar ferrule, solder and flux
Temperature 297 ยบF
Frequency 360 kHz
Equipment DW-UHF-4.5kW power supply with a specially designedย induction coil
Process A specially designed, 4-turn โ€œCโ€ shape coil was used to provideย uniform heat to the assembly near the joint area. With thisย design, the coil can be lowered directly onto the joint; it is notย necessary to feed the ferrule assembly through the coil. Fluxย was applied to the assembly where the ferrule and fiber opticย cable were to be joined. RF power was applied for 10 seconds,ย which caused the solder to melt and flow.
Results/Benefits Consistent and repeatable results were achieved with theย DW-UHF-4.5kW power supply and a 10-second heat cycle.ย The solder flowed evenly and bonded the fiber optic cable to
the Kovar ferrule. With the induction coilโ€™s compact design, aย very small surface area was heated with pinpoint accuracy.

induction soldering Fiber Optic cable

induction soldering fiber optic cable

Induction soldering fiber optic cable with high frequency induction heating units

Objective To heat a gold-plated ferrule and fiber optic cable to 475ยฐFย within 8 seconds for a soldering application
Material Gold-plated ferrule tube, fiber optic cable, solder preform
Temperature 475 ยบF
Frequency 270 kHz
Equipment DW-UHF-4.5kW power supply with a specially designedย induction coil.
Process A specially designed, two-turn plate concentrator coil was usedย to provide uniform heat to the fiber optic assembly. Theย assembly was placed in a specially designed fixture, thenย placed inside the induction coil. RF power was applied until theย solder flowed and created a solid joint.
Results Consistent and repeatable results were achieved using theย DW-UHF-4.5kW power supply and induction coil with a 5 to 7ย second heat cycle, depending on the type of solder used (seeย solder chart below).

Induction soldering fiber optic cable

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