Arnon (NGOES) Electrical Steel

Arnon (NGOES) Electrical Steel

Arnold Magnetic Technologies Non Grain Oriented (NGOES) Electrical Steel is optimized by thickness and finish to meet your most demanding needs for high speed, high efficiency motors and high efficiency transformer applications. When optimally applied, NGOES offers reduced eddy currents which translate into energy savings.


Arnold’s Non Grain Oriented Electrial Steel (NGOES) is manufactured in thicknesses of 0.004″, 0.005″ and 0.007″ (0.102mm, 0.127 mm and 0.178 mm) under the trade names Arnon™ 4, Arnon™ 5 and Arnon™ 7. Typical NGOES electrical steel laminations use 0.0118″ to 0.0185″ (0.30 mm to 0.47 mm) thicknesses.

Arnon™ silicon steel is frequently used as laminations in high speed, high efficiency motors and generators. Whereas common laminations use 0.014″ to 0.032″ (0.356 mm to 0.813 mm) thicknesses, Arnon 5 and Arnon 7 are thinner at 0.004″, 0.005″ and 0.007″ (0.102mm, 0.127 mm and 0.178 mm) respectively. The laminations are located in either the rotor or the stator depending on whether the laminated structure is used in a rotating or stationary design. The laminations are generally made from NGOES since they are circular and the magnetic properties are equal in all directions.

By using thinner laminations, your high speed motor and/or generator can achieve a higher level of performance through improved efficiency.

Arnon electrical steel has shown to be particularly advantageous for higher frequency motors and generators above 400 Hz. In these designs, the thinner material offsets the less efficient effects of increased eddy currents and subsequent heat buildup. Using thin laminations of Arnon produces a more efficient unit and frees up design constraints by allowing for fully enclosing the motor without external cooling, for example. Arnon laminations have proven to be the industry leader at switching frequencies above 1K Hz.

Arnon has the ability to lower core loss by as much as 50% compared to other NGOES materials. Some motors using Arnon have been tested to exceed 98% efficiency.

Learn More: GOES & NGOES – Controlling Internal Structure and Why it Matters


Slit Width MinimumSlit Width Maximum
Arnon™ 4 0.004″ (0.102mm)
0.20″ (5.08mm)
17.0″ (431.8mm) as rolled 16.5″ (419.1mm) with a slit edge
Arnon™ 5 0.005″ (0.127mm)
0.20″ (5.08mm)
17.0″ (431.8mm) as rolled 16.5″ (419.1mm) with a slit edge
Arnon™ 7 0.007″ (0.178mm)
0.20″ (5.08mm)
17.0″ (431.8mm) as rolled 16.5″ (419.1mm) with a slit edge

These materials are produced using our proprietary process that begins by rolling a heavier gauge 3% silicon steel to the required thickness and then “unorienting” it. This unique process creates a thin gauge steel with superior properties for use in Industrial, Aerospace, Defense, Semiconductor, and Medical applications.


Thin gauge Arnon provides efficiency improvements at higher frequencies above 400 Hz with exponential efficiency gains as the frequency increases.

  • Arnon is usable at higher frequencies than cobalt-iron materials. Co-Fe materials are not recommended for applications over 1200 Hz whereas Arnon Si-Fe is the preferred material to at least 10 KHz.
  • Low coercivity coupled with the hysteresis curve shape of Arnon provides reduced hysteresis loss in rotating machinery, yielding a more efficient motor or generator with less heat buildup and better performance (e.g. improved torque density) and/or the ability to maintain constant RPM’S under load.
  • Arnon exhibits up to 50% lower core loss than competitive non-oriented silicon steel when driven by the same field, confirming Arnon’s lower coercivity and improved hysteresis curve shape.
  • Low loss Arnon is especially useful in totally enclosed motor designs where heat cannot be easily removed.
  • Arnon is significantly less expensive than Co-Fe – about 1/3 its cost.

Our Arnon non grain oriented electrical steel (NGOES/CRNO) and grain oriented electrical steel (GOES/CRGO) materials meet IEC 60404-8-8.



We back up our Silicon Steels and other precision thin materials with extensive in-house lab and testing facilities that help our customers to get peak performance at a favorable cost. For service before and after the sale, the Arnold Precision Thin Metals team helps customers to verify the performance of materials and coatings under various ambient conditions and frequencies. Arnold’s advanced materials lab capabilities also allow us to test and assess mechanical characteristics to determine how the product is handled, stamped, and cut. Our unequaled technical know-how and support helps our customers to get the best in manufacturing and field performance from thin-rolled Silicon Steels, silicon steel sheet and other rolled metal products.

Arnold’s PTM business offers precision rolled Silicon Steels in a variety of thicknesses and orientations geared to standard applications. Silicon Steels from Arnold are available with or without standard C5 insulating coating and offer a choice of coatings chemistries for optimized performance.

Contact the PTM team to discuss your needs.


Check out the Material Thickness Reference Table

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