Amidst the trends toward higher operating frequencies and lightweight design in electric motors, ultra-thin non-oriented silicon steel—specifically grades with a thickness of 0.20 mm or less—is emerging as a core material in fields such as high-speed motors, drones, and high-frequency transformers. As a silicon steel manufacturer and direct exporter, Wuxi Zhongxin Special Steel supplies a comprehensive range of products, including grain-oriented silicon steel, non-oriented silicon steel, and ultra-thin silicon steel. This article systematically outlines the performance characteristics, grade distinctions, and application scenarios of ultra-thin non-oriented silicon steel ranging in thickness from 0.05 mm to 0.20 mm, thereby assisting overseas clients in making rapid and precise material selections.

What is non-oriented ultra-thin silicon steel?

Ultra-thin non-oriented silicon steel refers to cold-rolled non-oriented electrical steel strips (or sheets) with a nominal thickness of ≤0.20 mm. Through extreme thinning, eddy current losses at medium and high frequencies can be significantly suppressed, while simultaneously maintaining isotropic magnetic properties to meet the rigorous requirements of high-speed rotating motors and high-frequency electromagnetic components. Compared to materials of conventional thickness (0.35 mm and 0.50 mm), these ultra-thin specifications demonstrate a remarkably significant advantage in iron loss performance under high-frequency operating conditions.

The Relationship Between Thickness and Performance

The thinner the material, the lower the high-frequency core loss; however, the saturation magnetic induction and lamination factor will decrease slightly, and processing costs will rise accordingly. When selecting a material, it is necessary to strike a balance among core loss, magnetic induction, mechanical strength, and overall cost.

The following is a comprehensive comparison table of thicknesses and grades for non-oriented ultra-thin silicon steel.

 

Thickness (mm)	Chinese mill grade (enterprise standard)	Japanese mill grade (reference)	Typical core loss P1.0/400 (W/kg)	Typical induction B50 (T)	Remarks
0.05	B05A700	5JNEX900	≤7.0	≥1.58	Ultra-thin strip, mainly traded under mill grades
0.08	B08A800	8JNEX900	≤8.0	≥1.60	Same as above, mainly circulated as enterprise grades
0.10	B10AT900	10JNEX900	≤9.0	≥1.62	Mainstream high-frequency grade
0.10	B10AT1000	10JNE1000 series	≤10.0	≥1.62
0.10	10JNRF	10JNRF	≤10.0	≥1.62	Mill ultra-thin series
0.15	B15AT1000	15JNE1000	≤10.0	≥1.65	Widely used for UAV motors
0.15	B15AT1200	15JNE1200	≤12.0	≥1.65
0.15	—	15HX1000	≤10.0	≥1.64	High-performance series with lower core loss
0.18	B18AT1100	18JNE1100 series	≤11.0	≥1.65	Transitional thickness, for die upgrade application
0.20	B20AT1200	20JNE1200	≤12.0	≥1.66	Largest circulation among ultra-thin specifications
0.20	B20AT1300	20JNE1300	≤13.0	≥1.66
0.20	B20AT1500	20JNE1500	≤15.0	≥1.66
0.20	—	20HX1200	≤12.0	≥1.65	High-performance series

EN 10106 and ASTM A677 do not define grades at these gauges. Thin non-oriented steel for medium-frequency use is covered by EN 10303 / IEC 60404-8-8 — send us the standard on your drawing and we will cross-reference it. Japanese mill grades are listed for reference only; confirm against the mill’s current datasheet. Our own ultra-thin non-oriented grades, 05W-HF to 20W-HF with core loss quoted at P1.0/1000, are listed on the Ultra-Thin CRNGO page.

• 0.05mm Ultra-Thin Strip: Typically supplied in the form of narrow strips or slit coils. Minimum order quantities and lead times differ from those of standard specifications; we recommend communicating your specific requirements regarding width and coil weight in advance.
• For all thicknesses, self-adhesive coatings, custom slitting to specific widths, and customized hardness levels are available upon request.

Typical Application Scenarios

• UAV and eVTOL Propulsion Motors: 0.15 mm and 0.10 mm non-oriented ultra-thin silicon steel maintains low core loss at fundamental frequencies up to several kilohertz, delivering high rotational speed, high torque density and low heat generation.
• High-speed Spindle Motors and Compressors: Materials of 0.20 mm, 0.18 mm and 0.15 mm reduce core loss by over 30% compared with conventional 0.35 mm silicon steel, greatly improving energy efficiency.
• New Energy Vehicle Auxiliary Systems: 0.20 mm and 0.18 mm non-oriented ultra-thin silicon steel are increasingly adopted for electric power steering, electric water pump motors and other components to optimize system efficiency.
• High-frequency Power Supplies and Transformers: Ultra-thin gauges of 0.10 mm, 0.08 mm and even 0.05 mm effectively support power conversion from several kilohertz to tens of kilohertz and drastically downsize core dimensions.
• Precision Medical & Aerospace Industries: 0.05 mm and 0.08 mm ultra-thin strips feature extremely low high-frequency loss and excellent workability, ideal for special motors, sensors and ultra-high frequency transformers.

Industry	Typical Products	Recommended Thickness (mm)
New Energy Vehicles	Auxiliary motors, water pumps, oil pumps	0.20 / 0.18
New Energy Vehicles	On-board OBC / DC-DC transformers	0.10 / 0.08
UAV	Consumer & industrial grade motors	0.15 / 0.10
eVTOL	Propulsion motors	0.10
High-speed Motors	Electric spindles, electric turbines	0.20 / 0.15 / 0.10
Industrial Power Supplies	High-frequency transformers, reactors	0.10 / 0.08 / 0.05
Medical Equipment	High-speed dental drills, surgical drills, centrifuges	0.10 / 0.08
Precision Instruments	Sensors, instrument transformers	0.05
Aerospace	Actuators, special transformers	0.08 / 0.05

 

Why Choose Wuxi Zhongxin Special Steel?

• Complete product range down to 0.05 mm: We keep regular stock of non-oriented ultra-thin silicon steel coils and cut sheets in 0.20 mm, 0.18 mm, 0.15 mm and 0.10 mm. 0.08 mm and 0.05 mm materials are available for project-specific customization to meet full-range ultra-thin requirements.
• Diverse grades & flexible trial orders: We provide one-stop supply covering cost-effective domestic grades as well as high-performance materials compliant with Japanese and European standards. Small-batch mixed orders are supported for trial runs to minimize your inventory risks.
• Professional export packaging & documentation: Reinforced moisture-proof and rust-proof packaging is applied for sea and air transportation. We supply original mill certificates, chemical composition reports and magnetic performance curves, and can cooperate with third-party inspections upon request.
• Technical support for high-frequency applications: Our professional team can analyze stack thickness, magnetic circuit and operating frequency of your prototypes, and recommend the most cost-effective combination of thickness and steel grades.

Get Your Quotation for Non-oriented Ultra-thin Silicon Steel Now

Whether you need 0.2 mm coils for trial production or bulk purchase of 0.05 mm ultra-thin silicon steel cut sheets, please send us your drawings or grade requirements. We will provide detailed quotation and delivery schedule within 24 hours.