Ultrasonics, Plastics Joining, and Microjoining

Ultrasonic Machining


EWI has broad capabilities in high power ultrasonics (HPU), a technology based on the principal of converting electrical energy into mechanical energy for the purpose of changing the physical, chemical, or biological properties of materials or systems. We develop HPU technology in areas such as welding, additive manufacturing, machining, friction reduction, de-foaming, wire drawing, and cleaning. Our highly skilled technologists use state-of-the-art equipment to expand existing ultrasonics technologies and develop new ones. EWI’s expertise includes the design and fabrications of HPU systems, process development using design-of-experiments approaches, and quality control via in-process monitoring, nondestructive evaluation, and testing.

Laser Plastic Welding

Plastics Joining

EWI has a history of innovation in plastics joining, including development of the through-transmission infrared welding process. We work with all plastics joining processes, including ultrasonic welding, laser welding, adhesive joining, and spin welding. Joining of plastic parts requires consideration of a wide range of factors including material selection, joint design, environmental conditions, and cycle time. Our experts are intimately familiar with the advantages, disadvantages, and critical requirements of each unique process variation and can provide objective recommendations on process and equipment selection. Our customers benefit from this expertise as they tackle challenges related to product design, prototyping, production launch, and failure analysis.



EWI’s laboratory contains equipment for every joining process used in electronic and medical device assembly, including ultrasonic and thermosonic bonders, micro-TIG welders, and precision resistance welders. Resistance reflow soldering equipment and controlled-atmosphere furnaces are also part of this lab. Our experience in joining technologies, metallurgy, materials science, and design provide a complete solution for developing new products or increasing the efficiency of currently used manufacturing techniques.

EWI’s core competency in high power ultrasonics lies in the design and fabrications of novel power ultrasonic systems to suit an industry or client-specific need. We have capability in virtually all plastics joining technologies; however, our core strength lies in ultrasonic welding, laser welding, spin welding, and adhesive bonding. Our microjoining group uses ultrasonic, laser, arc, and resistance welding, as well as soldering and brazing to join small parts for the electronics and medical industry.

Technical Expertise


  • Metal welding
  • Machining
  • Forming
  • Additive manufacturing
  • Soldering
  • Wire drawing
  • Friction reduction
  • Defoaming
  • Cleaning
  • Food processing
  • HPU System design
  • Test and evaluation of HPU systems
  • Process development
  • Design of experiments
  • In-process monitoring
  • Test and evaluation of HPU processes
  • Nondestructive evaluation


  • Wire bonding
  • Ribbon bonding
  • Thermocompression bonding
  • Resistance welding
  • Parallel-gap welding
  • Micro-TIG welding
  • Laser welding
  • Soldering
  • Brazing
  • Data collection
  • Failure analysis
  • In-process monitoring
  • Materials Science
  • Design of experiments

Plastics Joining

  • Adhesives
  • Ultrasonic welding / inserting / staking / swaging / cutting / sewing
  • Laser welding (through-transmission and keyhole)
  • Laser surface treatment
  • Infrared welding (through -transmission and standard)
  • Spin welding
  • Vibration welding
  • Hot plate welding
  • Thermal staking
  • Thermal sealing of films
  • Extrusion welding
  • Hot gas welding
  • Implant induction welding
  • Resistive implant welding
  • Radio frequency welding
  • Material weldability and selection
  • Joint design / design for assembly
  • Tooling design
  • Process optimization and parameter development
  • Troubleshooting
  • Cross-Section / microtome analysis
  • CT scanning
  • Pull / peel / push / leak testing
  • Dynamic mechanical analysis
  • Fourier transform infrared spectroscopy
  • Differential scanning calorimetry
  • Microscopic analysis

Equipment and Lab Resources


  • Metal welding systems
    • Frequencies range from 15- to 60-kHz
    • Power ranges from 500- to 10,000-W
    • Lateral drive
    • Wedge-Reed
    • Torsion
    • Seam welders
  • Ultrasonic Assisted Machining
    • CNC Drilling and Milling
    • Single Point Turning
  • Additive manufacturing
  • Ultrasonic solder
  • PU system test and evaluation
    • Impedance analyzer
    • Laser vibrometer
    • Spectrum analyzer
Plastics Joining

  • Ultrasonic plastic welding equipment
    • 20 kHz servo press
    • 20 kHz pneumatic press
    • 20 kHz dual pneumatic press
    • 40 kHz pneumatic press
    • 15 kHz pneumatic press
    • 30 kHz servo press
    • 50 kHz probe & generator
  • Dual servo 4000 rpm spin welder
  • 940 μm laser diode with XY table
  • Microtome
  • Polarized light microscope
  • Plastic weld testing and evaluation equipment
    • 250 lb capacity peel tester
    • Dynamic machine analysis (DMA)
    • Fourier transform infrared (FTIR)
    • Differential scanning calorimetry (DSC)
    • Computed tomography (CT) Scanner

  • Ultrasonic wire bonder and metal welders from 20 to 60kHz, 10 to 800W
  • Resistance welders from 10A to 20kA
  • Parallel gap welding equipment to 1kA
  • Micro-TIG from 5A to 300A
  • Process monitoring
  • Furnaces from room temperature to 1500C, in high-vacuum, active and inert gases, air
  • Process monitoring of electrical, force, temperatures, humidity

Additional Capabilities

  • Static and fatigue testers
  • Metallographic and plastic cross-sectioning and imaging
  • Resistance measurement
  • High speed video
  • IR videography

Our high-impact projects have included:

  • Developing a repeatable micro-TIG welding process to join copper tabs for a battery application, with in-process measurement of weld energy as an indication of quality.
  • Conducting an in-depth laser welding evaluation for American Axle & Manufacturing, Inc. (AAM) to determine the processing window for joining 15% glass-filled nylon components, identifying settings for multiple key process variables, verifying that joint strength and leak rates were within allowable ranges, and positioning AAM to implement laser welding in future applications.
  • Developing a small-scale resistance spot welding procedure for Beckett Energy Systems (BES) to join lithium-ion cells into battery packs, assisting with electrode selection, weld schedule development, process monitoring techniques, design for weldability, and training.