O1 Cold Work Tool Steel Bars and Plates
This is a low-alloy cold-work die steel whose overall performance surpasses that of conventional CrWMn. It exhibits excellent machinability, making it easy to cut and form, and also possesses moderate hardenability and wear resistance. It experiences minimal distortion during quenching, with uniformly distributed carbides that are fine and well-refined. However, its weldability is relatively poor, necessitating strict preheating treatment.
Applications of O1
Primarily used in the field of small- and medium-sized cold-working dies that demand high dimensional accuracy and wear resistance. Typical applications include: precision blanking dies (such as parts for instruments and meters, and stator laminations for micro-motors); medium- and high-precision cold-forming dies (e.g., watch gears, miniature bearing cages); precision measuring tools (micrometer measuring surfaces, high-precision gauge blocks); and small plastic molding cores (e.g., optical lens molds, connector inserts).
Equivalent Grades and Commonly Used Specifications of O1
| Steel Grade | Specification | Specification Name |
| 9CrWMn / T20299 | GB/T 1299 | Tool and Mould Steels |
| O1/ T31501 | ASTM A681 | Standard Specification for Tool Steels Alloy |
| 1.2825 / 95MnWCr5 | DIN EN ISO 4957 | Tool Steels |
| SKS3 | JIS G 4404 | Alloy tool steels |
| Produce as other form and size according to technical requirements are available. | ||
Typical Chemical Composition of O1
|
Elements |
C | Si | Mn | P | S | Cr | W |
| % Mass Fraction | 0.85~0.95 | ≤0.40 | 0.90~1.20 | ≤0.030 | ≤0.030 | 0.50~0.80 |
0.50~0.80 |
| Produce as other form and size according to technical requirements are available. | |||||||
Typical Heat Treatment Condition and Mechanical Properties of O1
|
Delivery Condition |
Mechanical Properties and Hardness of Heat-Treated Specimens | ||||||
| Rp0.2/(N/mm2) | Rm/(N/mm2) | A/% | Zb/% | Aku2d/J | HBW |
HRC |
|
|
Annealed Condition |
/ | / | / | / | / | 197~241 | / |
| As-quenched Condition（800℃-830℃, oil） | / | / | / | / | / | / |
≥62 |
| Produce as other form and size according to technical requirements are available. | |||||||
Product Forms and Size Range of O1
|
Product forms |
Size range |
|
Bars |
Diameter or side length: 5.0mm~1000mm |
| Flats |
thickness: 4.0mm~1000mm width: 300mm~2200mm |
| Produce as other form and size according to technical requirements are available. | |
