Technical data for SUJ3 Steel for cold forming, complying with standard JIS G4805. Review the chemical composition, mechanical properties, and related technical requirements for this grade.
Supply and technical review · Creation Group accepts supply and technical review enquiries for this product. Dimensions, delivery condition, quantity and inspection documents are confirmed in the order technical agreement after review.
Elements not specified in this table shall not be intentionally added except for the purpose of finishing the molten steel, unless agreed upon between the parties involved. Note a) The Cu content in wire rod shall be 0.20% or less.
Elements not specified in this table shall not be intentionally added except for steelmaking purposes; any such addition shall be determined by agreement between the supplier and the purchaser. Note a) The Cu content in wire rod shall be 0.20% or less.
2. Mechanical properties of wire rod
Mechanical property values shall be determined by agreement between the supplier and the purchaser.
3. Dimensional Tolerances
4. Permissible Limits for Total Decarburized Layer Depth
Table 9 - Permissible Limits for Total Decarburized Layer Depth (Cold-Drawn Steel)
Cold-Drawn Round Bar
Cold-Drawn Wire
Diameter
Total decarburized layer depth from the surface
Diameter
Total decarburized layer depth from the surface
<15
<0.20
≤7
<0.05
15<d≤25
<0.25
7<d≤15
<0.08
25<d≤35
<0.30
15<d≤20
<0.10
Permissible tolerances for cold-drawn round steel with diameters exceeding 35 mm and cold-drawn steel wire with diameters exceeding 20 mm shall be subject to agreement between the supplier and the purchaser.
5. Hardness
Table 10 – Spheroidizing annealing hardness (rolled steel for machining)
Grade
Hardness
HBW
HRB
HV
SUJ3,SUJ5
<207
<95
<223
For hot-rolled steel for machining that has undergone spheroidizing annealing, testing is performed in accordance with Clause 14.3, and hardness is expressed as Brinell hardness (HBW), Rockwell hardness (HRBW), or Vickers hardness (HV) as specified in Table 10. However, Vickers hardness (HV) applies only to diameters of 17 mm or less. The hardness of cold-drawn steel and the low-temperature annealing hardness of steel for forging shall be subject to agreement between the supplier and the purchaser.
Engineering Knowledge
Cold Heading Material Engineering Classroom
TECHNICAL NOTE
Application and ordering note
Chemical composition, mechanical properties, delivery condition and other technical requirements are subject to the currently applicable standard edition, customer drawings and the order technical agreement. Website information does not replace formal quality certification documents.
RFQ CHECKLIST
What to include in the enquiry
Grade and applicable standard
Diameter or section, delivery condition and quantity
Part drawing, forming stations or failure photos, if available
Testing, certificate or report requirements
RELATED CAPABILITIES
Related manufacturing and quality capabilities
Carbon equivalent calculator — SUJ3
Basis: JIS G4805
Chemical composition source: JIS G 4805:2008
Transcribed from the cited standard
Original source wording
Table 1
IIW / CEV
CEV = C + Mn/6 + (Cr + Mo + V)/5 + (Ni + Cu)/15Known-element contribution, not a complete value: 1.2800–1.5777
Missing elements: V
IIW/CEV: carbon and low-alloy steel weldability screening.
Pcm (Ito–Bessyo)
Pcm = C + Si/30 + (Mn + Cu + Cr)/20 + Ni/60 + Mo/15 + V/10 + 5BKnown-element contribution, not a complete value: 1.0533–1.2603
Missing elements: V, B
Pcm: mainly low-carbon, low-alloy steels; confirm applicability, particularly when C exceeds 0.11%.
CET
CET = C + (Mn + Mo)/10 + (Cr + Cu)/20 + Ni/40Calculated range: 1.0850–1.2993
CET: ferritic-steel preheat assessment; confirm EN 1011-2 conditions.
A stated upper limit means 0 to that limit. A lower limit alone does not define an upper bound. Missing elements are unknown, not zero. Standard-limit combinations are not measured heat results.
Carbon equivalent supports weldability assessment; it does not approve cold heading, fastener strength or a welding procedure. These formulas do not directly apply to stainless steels, cast irons or non-ferrous metals.
