Manufacturer, Supplier & Exporter of O1 Tool Steel Round Bar

O1 Tool Steel is a classic high-carbon, oil-hardening tool steel renowned for its excellent machinability, good wear resistance, and ability to be heat-treated to a relatively high hardness, making it ideal for cold-work tooling. The material offers a good balance of toughness, hardness, dimensional stability and ease of machining, which makes it a widely used steel for dies, punches, cutting tools, gauges, and general-purpose tooling. As a standard tool steel, O1 is often chosen when cost-effectiveness, ease-of-finish, and reliable performance matter...

Riddhi Siddhi Impex manufactures and supplies O1 Tool Steel Round Bars across India, offering stock lengths, custom cuts and tailored bar sizes to meet diverse industrial needs. With a broad distribution network, they deliver to major Indian cities and industrial hubs — from metropolitan centers like Mumbai, Delhi, Bengaluru (Bangalore), Hyderabad, Chennai, Kolkata, Pune, Ahmedabad, Surat, Vadodara — to tier-2 and industrial belt cities including Rajkot, Nagpur, Indore, Bhopal, Jaipur, Kanpur, Lucknow, Agra, Varanasi, Amritsar, Chandigarh, Mysuru (Mysore), Udaipur, Jodhpur, Visakhapatnam, Coimbatore, Madurai, Kochi, Thiruvananthapuram, Mangalore, Nashik, Kolhapur, Chandrapur, Akola, as well as industrial zones such as Vilayat, Dahej, Ankleshwar, Navsari, Valsad, Rajpipla, and others. This widespread availability positions Riddhi Siddhi Impex as a trusted O1 Tool Steel Round Bar domestic supplier.

O1 Tool Steel Round Bars from Riddhi Siddhi Impex are available in a variety of diameters and lengths, accommodating small tool shops to large-scale manufacturing units. The bars are supplied in annealed condition for ease of machining, but customers can also request pre-machined blanks, ground bars, or bars ready for hardening and finishing. This flexibility helps manufacturers reduce lead times and streamline production cycles..

One of the key benefits of O1 Tool Steel Round Bar is its excellent machinability — even in the annealed condition — which makes it well suited for producing complex shapes, close tolerances, and fine finishes. Because of its balanced composition and controlled heat-treatment, it is relatively easy to grind, drill, mill or turn, reducing tool wear and machine time compared to more abrasive high-alloy steels. This makes it a preferred choice for smaller workshops as well as large fabricators seeking cost-effective tooling solutions...

After appropriate hardening and tempering, O1 Tool Steel bars can achieve good hardness (typically around 58–62 HRC, depending on section size and heat treatment), making them suitable for applications where good wear resistance and dimensional stability are required. Tools manufactured from O1 often deliver long service life in cold-work operations — such as stamping, blanking, cold punching, forming dies — where high hardness and resistance to deformation are essential..

O1 Tool Steel Round Bar

Specification

Product Name	O1 Tool Steel Round Bar
Manufacturer	Riddhi Siddhi Impex
Grade	O1 Oil-Hardening Tool Steel
Standard	ASTM A681 / DIN 1.2510 / JIS G4404
Size Range	10 mm to 350 mm Diameter
Length	1000 mm to 6000 mm (Custom Cut Available)
Condition	Annealed, Spheroidized, Hardened & Tempered
Manufacturing Type	Hot Rolled, Cold Drawn, Forged
Surface Finish	Black, Polished, Peeled, Turned
Applications	Cutting Tools, Dies, Blades, Punches, Gauges, Precision Tools

Chemical Composition

Element	Content (%)
Carbon (C)	0.90 – 1.00
Manganese (Mn)	1.00 – 1.40
Silicon (Si)	0.10 – 0.40
Chromium (Cr)	0.50
Tungsten (W)	0.40 – 0.60
Vanadium (V)	0.20 – 0.30
Nickel (Ni)	0.30 Max
Copper (Cu)	0.25 Max

Mechanical Properties

Property	Value
Tensile Strength	≥ 740 MPa
Yield Strength	≥ 480 MPa
Hardness (Annealed)	200 – 250 HB
Hardness (Hardened)	57 – 62 HRC
Elongation	≥ 10%
Impact Resistance	Moderate to High

Dimension Chart (Nominal)

Diameter (mm)	Diameter (Inches)	Standard Length
10	0.39"	1000–6000 mm
20	0.78"	1000–6000 mm
30	1.18"	1000–6000 mm
50	1.96"	1000–6000 mm
75	2.95"	1000–6000 mm
100	3.93"	1000–6000 mm
150	5.90"	1000–6000 mm

Equivalent Grades

Standard	Equivalent Grade
ASTM	O1
DIN	1.2510
JIS	SKS3
BS	BO1

Equivalent Standards

Standard	Description
ASTM A681	Standard Specification for Tool Steels
DIN 17350	Tool Steel Technical Delivery Conditions
JIS G4404	Tool Steel Bars Specification
BS 4659	Tool and Alloy Steel Standards

Other Types of Tool Steel

Type	Description
A2 Tool Steel	Air-hardening tool steel with high wear resistance
D2 Tool Steel	High-carbon, high-chromium cold work tool steel
H13 Tool Steel	Hot-work tool steel used in die casting & extrusion
W1 Tool Steel	Water-hardening tool steel for simple tooling

Due to its composition (moderate carbon, chromium, tungsten/vanadium traces), O1 offers acceptable toughness and shock resistance for many applications, though it is not intended for heavy hot-work or high-temperature environments. For cold work, press tools, gauge blocks, jigs, and fixtures that remain at or near room temperature, O1 remains a go-to tool steel. Its relative ease of heat treatment and straightforward tempering also makes it user-friendly for small and medium scale tool shops..

Frequently Asked Questions (FAQs)

Q1: What are the main applications of O1 Tool Steel Round Bar?

A1: It is used for punches, cutting tools, dies, gauges, knives, and precision tool components.

Q2: Can O1 Tool Steel be hardened?

A2: Yes, O1 is oil-hardening and achieves up to 62 HRC after proper heat treatment.

Q3: Do you offer custom cut sizes?

A3: Yes, Riddhi Siddhi Impex provides custom-cut O1 Tool Steel Round Bars as per requirement.

Q4: Is O1 Tool Steel corrosion resistant?

A4: O1 has moderate corrosion resistance; oiling is recommended for long-term storage.