S45C Hexagonal Bar JIS G4051 Carbon Steel Hexagon Bar for Fastener & Machinery Parts

Meets JIS G4051 standard with stable chemical & mechanical performance
Excellent machinability, suitable for quenching and tempering heat treatment
Near-net hexagonal shape, reduces machining time for fastener production
Available in cold drawn bright surface & hot rolled black surface
Complete across-flat size range S8-S100, MTC provided for every batch

Product Overview

S45C Hexagonal Bar is medium carbon steel hex bar produced in accordance with JIS G4051 specification. It is a solid six-sided carbon steel raw material widely used for fastener blank, machinery shafts, gears and hydraulic components.

This S45C hexagonal bar can be supplied in hot rolled black finish or cold drawn bright finish. Cold drawn version achieves tighter dimensional tolerance and smoother surface. With balanced strength and hardness, S45C material can be heat treated to improve wear resistance and mechanical property.

Our S45C hex bar covers across-flat dimension S8 to S100, including standard sizes and customized non-standard sizes. Every shipment is supplied with Mill Test Certificate, fully traceable heat number. It is widely exported to machinery manufacturing, automotive and hydraulic industries for bolt, nut, wrench blank and precision mechanical parts fabrication.

Carbon Steel Hexagonal Bar

Chemical & Mechanical Property Snapshot

Grade	Standard	C (%)	Mn (%)	Si (%)	S (%)	P (%)	Yield Strength (MPa)	Tensile Strength (MPa)	Elongation (%)
S45C	JIS G4051	0.42~0.48	0.60~0.90	0.15~0.35	≤0.030	≤0.035	≥345	570~740	≥20

Detailed Technical Specifications

Item	Specification
Product Name	S45C Hexagonal Bar
Material Grade	S45C
Standard	JIS G4051
Cross Section	Hexagonal / Six-sided solid bar
Across-Flat Dimension	S8 – S100
Standard Hex Sizes	S8, S10, S12, S14, S17, S19, S22, S24, S27, S30, S32, S36, S41, S46, S50, S55, S60, up to S100
Surface Finish	Hot-rolled black surface / Cold-drawn bright surface
Profile Advantage	Near-net-shape hexagonal profile reducing machining preparation
Main Processing	Machining, heat treatment, fastener production, component fabrication
Quality Certificate	Mill Test Certificate with heat number, chemical composition and mechanical test records
Packaging	Steel strapped bundles for seaworthy export packing
MOQ	5 Ton
Payment Terms	T/T, L/C at Sight
Delivery Time	7–15 working days after receiving deposit

Size Dimension Table

Item	Specification
Product Name	Carbon Steel Hexagonal Bar
Across-flat Size (S)	S8, S10, S12, S14, S17, S19, S22, S24, S27, S30, S32, S36, S41, S46, S50, S55, S60, S65, S70, S75, S80, S85, S90, S95, S100
Length	3–6 m standard length; custom cut length available
Tolerance	Cold drawn: h9/h11; Hot rolled: GB/T 705 standard tolerance
Cross Section	Hexagonal solid bar
Surface Finish	Hot-rolled black surface / Cold-drawn bright surface

Product Comparison Table

Comparison Item	S45C Hexagonal Bar	45# Hexagonal Bar	1018 Hexagonal Bar	1045 Hexagonal Bar	S235JR Hexagonal Bar
Equivalent Standard	JIS G4051	GB/T 699	ASTM A108	ASTM A108	EN 10277 (Base EN10025-2)
Material Type	Medium Carbon Steel	Medium Carbon Steel	Low Carbon Steel	Medium Carbon Steel	Low Carbon Structural Steel
Carbon Content (C)	0.42~0.48%	0.42~0.50%	0.14~0.20%	0.43~0.50%	≤0.17%(≤16mm); ≤0.20%(>16mm)
Silicon Content (Si)	0.15~0.35%	0.17~0.37%	≤0.60%	0.15~0.35%	≤0.35% (no minimum required)
Manganese Content (Mn)	0.60~0.90%	0.50~0.80%	0.60~0.90%	0.60~0.90%	≤1.40%
Phosphorus (P) Max	≤0.030%	≤0.035%	≤0.040%	≤0.040%	≤0.035%
Sulfur (S) Max	≤0.035%	≤0.035%	≤0.050%	≤0.050%	≤0.035%
Min Yield Strength (Hot Rolled / Normalized)	≥345 MPa	≥355 MPa	≥205 MPa (Typical 250–330MPa for cold drawn)	≥355 MPa	≥235 MPa (≤16mm)
Tensile Strength	570~740 MPa	≥600 MPa	415–520 MPa	585~700 MPa	360–510 MPa
Elongation (A5 Min)	≥17%	≥16%	≥25%	≥16% (annealed)	≥25%
Manufacturing Process	Cold Drawn / Hot Rolled	Cold Drawn / Hot Rolled	Cold Drawn / Hot Rolled	Cold Drawn / Hot Rolled	Cold Drawn / Hot Rolled
Surface Condition	Bright cold drawn / Black hot rolled	Bright cold drawn / Black hot rolled	Bright cold drawn / Black hot rolled	Bright cold drawn / Black hot rolled	Bright cold drawn / Black hot rolled
Size Range (Across Flat)	6mm – 80mm	6mm – 80mm	6mm – 80mm	6mm – 80mm	6mm – 80mm
Dimensional Tolerance	Cold drawn: ±0.02~0.1mm; Hot rolled: ±0.3~1.0mm	Cold drawn: ±0.02~0.1mm; Hot rolled: ±0.3~1.0mm	Cold drawn: ±0.02~0.1mm; Hot rolled: ±0.3~1.0mm	Cold drawn: ±0.02~0.1mm; Hot rolled: ±0.3~1.0mm	Cold drawn: ±0.02~0.1mm; Hot rolled: ±0.3~1.0mm
Main Application	Shafts, gears, hydraulic parts, machinery components	Machinery shafts, gears, mold parts, structural components	Fasteners, pins, general machinery, welding parts	Axles, gears, machine tool components	European standard structural parts, brackets, frames
Cost Level	Medium-High	Medium-High	Medium	Medium-High	Medium
Feature	Good hardness & machinability, suitable for quenching & tempering	Good comprehensive strength, can be heat treated	Excellent weldability & ductility, easy bending	High tensile strength, good heat treatment performance	Excellent weldability, CE compliance, general structural use

App Market

Reliable Steel Coil Solutions For Diverse Industrial Applications

Hydraulic Fittings

Hexagon Head Bolts

Nuts and Threaded Rods

Product Packaging

Secure Export Packaging For Safe Handling And Delivery

FAQs

What is S45C hexagonal bar standard?

S45C hexagonal bar complies with JIS G4051, Japanese standard carbon steel bar for machine structural use.

Can S45C hex bar be heat treated?

Yes. S45C medium carbon steel supports quenching and tempering to improve hardness and wear resistance for gears and shafts.

What is the difference between S45C and 45# hexagonal bar?

S45C follows JIS G4051, 45# follows GB/T699. Chemical composition is close, but inspection standards and tolerance requirements are different.

What surface types of S45C hexagonal bar can you supply?

Two options: hot rolled black surface, cold drawn bright surface with tighter tolerance.

Do you provide Mill Test Certificate for S45C hexagonal bar?

Yes, MTC including heat number, chemical composition and mechanical test results will be provided for each batch.

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S45C Hexagonal Bar JIS G4051 Carbon Steel Hexagon Bar for Fastener & Machinery Parts