Soldering & Brazing

In addition to deep knowledge of all process variations including lead-free soldering and vacuum brazing, EWI’s innovative ultrasonic soldering and brazing processes facilitate the bonding of previously problematic dissimilar joints such as ceramic to metal or metal to glass.

EWI’s soldering and brazing group offers unparalleled client support in application-specific material selection and process development. We use furnaces, lasers, torches, resistance welders, induction heaters, and soldering irons to provide accurate control of heat application to flow the solder or braze alloy.

Soldering and Brazing

Our team assists customers with the design of brazed and soldered assemblies, the selection of base and solder materials, inspection, and the testing of assemblies after joining. In addition, we’ve applied our innovative ultrasonic soldering and brazing processes to metals, ceramics, glass, and composites. Through an in-depth understanding of all types of brazing and soldering, our experts lead impactful projects across a wide variety of industries, offering innovative solutions to join challenging and/or dissimilar material combinations including graphite, ceramics, glass, and metals.

EWI’s soldering and brazing group has over 45 years of combined experience in the medical device, aerospace, electronics, advanced energy, appliance, and consumer goods industries. From ultrasonic soldering of glass components to vacuum furnace brazing of ceramic/metal joints, EWI has expertise in soldering and brazing a broad assortment of materials for a wide variety of applications. This suite of capabilities allows us to join the following dissimilar materials combinations:

  • Silicon Carbide (SiC)/Inconel (vacuum and inert atmosphere furnace and laser brazing)
  • SiC/Ti-6-4 panels (ultrasonic soldering)
  • Graphite/W-Cu, Mo-Cu (inert atmosphere furnace brazing)
  • Doped Ceria/Ni-base alloys (vacuum furnace brazing)
  • CP Ti/graphite fibers (ultrasonic soldering)
  • Al/glass (ultrasonic soldering)
  • SiC-diamond composite/steel (ultrasonic soldering)
  • Zinc aluminum oxide/stainless steel (ultrasonic soldering)
  • Alumina/stainless steel (induction and resistance brazing)

Additional Technical Expertise

  • Joint design and filler alloy selection
  • Feasibility assessments
  • Parameter development
  • Procedure development
  • Mechanical property characterization
  • Optical and electron microscopy
  • Failure analysis
  • Wettability test development
  • Quantitative measurement of contact angles
  • Characterization of interface reactions
  • Torch soldering and brazing
  • Hot plate soldering and brazing
  • Induction soldering and brazing
  • Resistance soldering and brazing
  • Laser soldering and brazing

Equipment and Lab Resources

  • Lindberg quartz tube furnace, 2.75-in diameter x 24-in long hot zone, 1200°C max temperature
  • Lindberg quartz tube furnace, 5-in diameter x 24-in long hot zone, 1200°C max temperature
  • Hot press furnace, 14-inx16-inx21-in graphite hot zone, 1500°C max temperature, 50-ton vertical force capability
  • Multiple commercially available ultrasonic power supplies (20-60 kHz and up to 1300W) and transducers with custom tooling
  • Sunbonder IV (60 kHz, 10W) ultrasonic soldering iron with 1-4 mm diameter tips
  • Ultrasonic soldering pots – Blackstone-Ney (45 kHz and 300W) with 9-inx4-inx3-in pots, with Sn-Pb, EWI SonicSolder™, and Zn-5Al.

Our high-impact projects have included:

  • Developing an ultrasonic soldering procedure to join wear-resistant SiC-diamond ceramic composite to steel for an oil and gas exploration application, overcoming challenges associated with the significant difference in coefficient of thermal expansion of the two materials by creating a low-temperature high-strength bond which exceeded the minimum pushout force requirement by up to 50%.
  • Enabling the use of thinner advanced high-strength steels by using a low-temperature brazing alloy and developing a low-heat input brazing procedure which does not detrimentally affect mechanical properties.
  • Vacuum furnace brazing a bimetallic honeycomb core to a niobium facesheet using a palladium-nickel alloy, allowing the assembly to be used in a high-temperature application.
  • Reflow soldering gold wire on a copper bond pad for a nano-structured electronics application.
  • Assembling a silicon carbide cap onto a mock nuclear fuel rod of the same material using an Al-Si braze filler alloy. This assembly successfully endured thermal cycling to 1200°C followed by a 6-month simulated nuclear reactor core exposure.
  • Evaluating an alternate braze alloy in support of a customer cost reduction initiative, with potential for over $600k annual savings.
  • Ultrasonically soldering glass to metal for vacuum-insulated glass joints subject to helium leak testing.
  • Using an ultrasonically-applied low-melting layer in a transient liquid phase bond between metal and ceramic for moderately high temperature service environments.
  • Ultrasonically soldering metal end caps onto metal-matrix composite tubes for high-pressure temperature-sensitive application