Technology and Manufacturing Capabilities

ALON® or Aluminum Oxynitride is an amazing and unique transparent advanced ceramic that is polycrystalline (made from powder) with a cubic spinel crystal structure. In the popular media and in the Star Trek community, it is commonly referred to as Transparent Aluminum. Surmet is the only company globally, that manufactures ALON®.

Taking over the development of ALON® from a laboratory demonstration stage in 2002, Surmet is proud to announce the commercial availability of ALON® in large volumes and in really large sizes. Over the last 12 years, Surmet has invested large sums of monies to build up its vertically integrated optical ceramics manufacturing capability. Surmet gratefully acknowledges US DOD funding help in this accomplishment. Creating such a capability required a great deal of patience and attention to detail, and complete commitment, as the return on investment for new technology materials is a slow, uncertain  and painstaking endeavor.

18x35 ALON window

Today Surmet manufactures precision ALON® components with consistently high quality, in batches that are in tonnage quantities, and in increasing sizes and shape complexity. Surmet has capability to produce precisely finished ALON components and is the only supplier of monolithic windows as big as 18x35-inch and windows with engineered seams as large as 24x27-inch to the US Defense market.

ALON parts

Recommended ALON® Publications

ALON® Optical Ceramic Transparencies for Sensor and Armor Applications

Transparent Cubic Spinels Protect and Defend

Characterization of ALON® Optical Ceramic

ALON® Optical Ceramic's Key Features

  • Transparent: High optical transmission (>85%) near-UV to mid-IR wavelengths (0.25 to 4.0 μm)
  • Crystal clear: Excellent clarity and no inherent birefringence
  • Durable: Outstanding hardness, scratch resistance and high strength
  • High quality: Excellent Refractive index homogeneity over large areas
  • Commercially available: Available in large sizes up to 18x35-in windows as well as in various shapes including hyperhemispherical and hemispherical domes in large quantities..
  • Robust process: Produced using very robust process with consistently high quality and yields
  • Enormous Broad Application Potential: Applicable to a wide variety of industries where combination of high transparency and durability are needed. Examples include aerospace, security,  defense and semiconductor, Energy, mining and consumer products.


ALON Transparent Armor for Helicopters and aircraft ALON Transparent Armor for Helicopters and aircraft

ALON Transparent Armor for Helicopters and aircraftALON Transparent Armor for Helicopters and aircraft

ALON® Optical Ceramic Properties

Grain Size (typical):
150-250 microns
Cubic, Spinel
3.696 - 3.691 g/cc
Melting Point:
Young's Modulus:
323 GPa
1850 kg/mm2 (Knoop Indent, 200g)
Fracture Toughness:
Flexure Strength:
380-700 MPa
Thermal Conductivity
13 W/mK
Transmission Limits:
0.22 to 6 microns

Large ALON window with engineered seems
Large ALON® window with invisible engineered seams.