Nickel-plated Steel Sheet (Ni-Top)

Ni-Top was developed utilizing Toyo Kohan's superior rolling technology and innovative surface treatment technologies. Its excellent formability, dimensional accuracy and corrosion resistance have been highly acclaimed worldwide.
With abundant experience and environmental friendly technology, Toyo Kohan is confident in introducing Ni-Top to meet the increasing demands for quality and the needs of our valued customers.

Toyo Kohan in Your Everyday Life


Feature 1 Technology

The integration of the world class surface treatment and rolling technology realized high performance and high precision Ni-Top with excellent exterior appearance.

Feature 2 Superior Workability

Diffusion annealing process improves plating adhesion and corrosion resistance of the product and enhances the product’s processing suitability.

Feature 3 Quality

Toyo Kohan maintains stability of product function and quality by placing strict control on quality management.

Type Specification Sturcture Features
Diffusion Annealed
Diffusion Annealed (Semi-Gloss, Matte)
  • Soft Ni
  • Ni-Fe Diffusion Layer
  • Steel
  • Excellent heat and corrosion resistance.
  • Diffusion annealing process reduces rusting caused by cracks at stamping process as it improves plating adhesion and workability of the plating layer.
  • Gloss Ni
  • Steel
  • Excellent heat and corrosion resistance.
  • Smooth and beautiful gloss finish surface.
  • Less seizing on die during stamping due to hard plating surface with low friction coefficient.
  • Matte Ni
  • Steel
  • Excellent heat and corrosion resistance.
  • Low contact resistance that is stable over time.
  • Semi-Gloss Ni
  • Steel
  • Excellent heat and corrosion resistance.
  • Low contact resistance that is stable over time.
  • Smooth and semi-gloss surface finish.

From standard industry products to leading-edge products, Ni-Top is used in various applications around the world.

Battery Parts

Toyo Kohan supplies nickel plated steel to various batteries types.

Alkaline batteries

Lithium-ion batteries

Flat Parts

Vehicle Parts

Superior resistance to deterioration, gasoline, heat, exhaust gases, etc.

Fuel pipe


Perforated core body material processed with our proprietary rotary press system is mainly used for battery parts used in hybrid automobiles.

Perforated core body material

Electrical and Electronic Parts

Adapt to high temperature processing.

Stepping Motors


Glossy surface finish is available.



Plating Structure

Fe-Ni diffusion layer is derived by thermal process.

Diffusion Annealed Ni-Top As Plated Ni-Top
  • Soft Ni
  • Ni-Fe Diffusion layer
  • Steel
  • Ni
  • Steel
Ni, Fe distribution in depth direction by GDS GDS method based Ni, Fe depth direction distribution measurement example (Thermal Diffusion Process Ni-Top) GDS method based Ni, Fe depth direction distribution measurement example (As nickel plated)

Electric Contact Resistance

Measurement example: AC 4 terminal method, contact load 100 g, gold 1.0 mm terminals

Resistance (mΩ) Initial After
Matte 2.9 6.2
Semi-gloss 2.5 7.3
Gloss 3.1 49
Diffasion Annealed 2.9 8.9

*Over time: 60℃×95% RH× 2 weeks

Corrosion Resistance

Comparison of Eriksen Corrosion Resistance

Diffusion annealed Ni-Top has excellent processing properties and has less cracks during processing. Therefore, the product is prevented from corrosion.

Type / Test item Diffusion Annealed Ni-Top As Plated Ni-Top
Cu-sulfate (5%)
Solution Temp; 35˚C
Immersed Time ; 10s
Eriksen; 7mm
Thermal Diffusion Process Ni-Top As nickel plated

* Sheet Thickness 0.25mm, Plating Thickness; 3 µm

Comparison between as plated Ni-Top and dissusion annealed Ni-Top

Elongation 0% 10% 20% 25%
Diffusion Aneealed Ni-Top K treatment 0% nickel plating K treatment 10% nickel plating K treatment 20% nickel plating K treatment 25% nickel plating
As Plated Ni-Top 0% nickel plating 10% nickel plating 20% nickel plating 25% nickel plating

* Plating Thickness; 3 µm. JIS Z 2371 5% saltwater at 35℃ for 2 hours, tensile test distortion added (JIS specimen #5)

Charged Voltage and Tensile Shear Strength

Detailed settings are not required since welding condition range is wide.

Available Sizes

Available Size Range

Plating Thickness

Plating Thickness
same amount for Top/Bottom
Plating Thickness
different amount for Top/Bottom
Plating Thickness (µm) Plating Weight (g/m²)
0.25/0.25 2.23/2.23 Please contact us if different plating thickness is required on each side.
0.5/0.5 4.45/4.45
1.0/1.0 8.9/8.9
2.0/2.0 17.8/17.8
3.0/3.0 26.7/26.7
4.0/4.0 35.6/35.6
5.0/5.0 44.5/44.5
6.0/6.0 53.4/53.4
10.0/10.0 89.0/89.0
  • Toyo Kohan guarantees Ni plating amount in thickness.
  • Plating thickness is available with 0.5 µm increments in between.
Standard Products

Temper Grades

Wide range of properties are available in required specifiation.

Standard; Equivalent to JIS standards G-3141
Type Tamper Grade Code Hardness
(Standard Temper)
SB Less than 116 Less than 60
(1/4 hardness)
SU4 116 to 151 60 to 70
(1/2 hardness)
2 135 to 179 66 to 76
1 1 More than 164 More than 73
SPCD S SD Less than 116 Less than 60

Chemical Composition

Type C Mn P S Fe
SPCC Less than 0.15 Less than 0.60 Less than 0.100 Less than 0.035 Bal
SPCD Less than 0.10 Less than 0.50 Less than 0.040 Less than 0.035 Bal

Surface Finish

Different surface finish are avalilable by selecting finely polished roll or dull roll.

Surface Finish Code Description
Dull Finish D Lusterless and technically roughly finished.
Bright Finish B Smooth and flat finish.