Cal Nano Services

Diffusion Bonding

High-Integrity Solid-State Joining for Advanced Materials

 

Diffusion bonding is a solid-state joining process that permanently bonds materials without melting them. By applying controlled heat and pressure, atoms diffuse across the interface between two surfaces, creating a seamless metallurgical bond with strength approaching that of the base materials.

 

Because the process occurs below the melting point, diffusion bonding avoids many of the challenges associated with welding or brazing, including heat-affected zones, filler materials, and distortion. The result is a clean, high-integrity joint capable of performing in demanding environments.

 

At California Nanotechnologies, diffusion bonding is often performed using Spark Plasma Sintering (SPS / FAST) technology. SPS enables rapid heating rates, precise pressure control, and vacuum or controlled atmosphere processing, allowing complex material systems to be bonded quickly and reliably.

 

This capability is particularly valuable for joining dissimilar materials, multi-layer structures, refractory metals, and advanced ceramics, making diffusion bonding a key manufacturing technique for aerospace, nuclear, energy, and advanced materials applications.

 

Engineering Support

Each project begins with a technical review to determine the optimal bonding parameters based on material system, geometry, and application requirements.

Services include:

  • Process development and feasibility studies

  • Prototype manufacturing

  • Tooling and fixture design

  • Bond characterization and testing

  • Scale-up for production manufacturing

California Nanotechnologies provides diffusion bonding services for a wide range of advanced materials, geometries, and component sizes. Our Spark Plasma Sintering (SPS / FAST) systems enable precise control of temperature, pressure, and atmosphere to produce high-integrity bonds.

Materials

We routinely work with a variety of advanced materials including:

Metals and Alloys

  • Titanium and titanium alloys

  • Stainless steels

  • Nickel-based superalloys

  • Aluminum alloys

  • Copper and copper alloys

Refractory Metals

  • Tungsten

  • Molybdenum

  • Tantalum

  • Niobium

Ceramics and Advanced Materials

  • Boron carbide

  • Silicon carbide

  • Aluminum nitride

  • Metal-matrix composites

We also support dissimilar material bonding, including metal-to-metal, metal-to-ceramic, and multi-material layered structures.

Part Size Capability

Using our Spark Plasma Sintering systems, California Nanotechnologies can diffusion bond components up to approximately:

  • Up to 400 mm (16 in) diameter

  • Up to ~200 mm (8 in) height / stack thickness

These capabilities allow us to produce bonded structures such as:

  • Multi-layer material stacks

  • Laminated composites

  • Functionally graded materials

  • Complex assemblies requiring high structural integrity

For specialized applications, our team can evaluate custom tooling or fixturing to support different geometries.

Process Capabilities

Our diffusion bonding services include:

  • SPS / FAST assisted diffusion bonding

  • Vacuum and controlled atmosphere processing

  • Rapid heating and controlled cooling cycles

  • Precise axial pressure control

  • Multi-layer structure fabrication

  • Joining of dissimilar materials

 

Aerospace and Defense

The process is commonly used to produce lightweight, high-performance components capable of operating in extreme thermal and mechanical environments.

Typical applications include:

  • Turbine and propulsion components

  • Rocket and hypersonic system hardware

  • High-temperature structural components

  • Multi-layer heat exchangers

Nuclear and Energy Systems

Diffusion bonding allows the integration of materials designed for radiation resistance, thermal stability, and long-term reliability.

Applications include:

  • Reactor components and assemblies

  • Neutron absorber structures

  • Thermal management components

  • Advanced energy system hardware

Electronics and Thermal Management

For systems requiring high thermal conductivity and dimensional precision, diffusion bonding provides a reliable joining method without introducing filler materials.

Examples include:

  • Heat spreaders

  • Semiconductor packaging components

  • Copper-based thermal management structures

Advanced Materials and Composites

Diffusion bonding is frequently used in research and advanced manufacturing to create novel material systems.

Examples include:

  • Functionally graded materials (FGMs)

  • Metal-ceramic assemblies

  • Multi-layer composite structures

  • Advanced experimental materials