Properties
Dimension
| Property | Value |
|---|---|
Dimensions | Please feel free to check the figure on the right side of the material page for more details. |
Mechanical
| Property | Value | Comment |
|---|---|---|
Elongation | 10 % Show Supplier Material materials with Elongation of 10 % | Quenched | 6 mm specimen in the rolling direction |
27 % Show Supplier Material materials with Elongation of 27 % | Delivery condition | 6 mm specimen in the rolling direction | |
Hardness, Rockwell C | 45 [-] Show Supplier Material materials with Hardness, Rockwell C of 45 [-] | Quenched | 6 mm specimen in the rolling direction |
Tensile strength | 520 MPa Show Supplier Material materials with Tensile strength of 520 MPa | Delivery condition | 6 mm specimen in the rolling direction |
1500 MPa Show Supplier Material materials with Tensile strength of 1500 MPa | Quenched | 6 mm specimen in the rolling direction | |
Yield strength | 350 MPa Show Supplier Material materials with Yield strength of 350 MPa | Delivery condition | 6 mm specimen in the rolling direction |
1100 MPa Show Supplier Material materials with Yield strength of 1100 MPa | Quenched | 6 mm specimen in the rolling direction |
Chemical properties
| Property | Value | Comment |
|---|---|---|
Aluminium | 0.02 % Show Supplier Material materials with Aluminium of 0.02 % | min. |
Boron | 0.002 - 0.005 % Show Supplier Material materials with Boron of 0.002 - 0.005 % | |
Carbon | 0.2 - 0.25 % Show Supplier Material materials with Carbon of 0.2 - 0.25 % | |
Manganese | 1.1 - 1.4 % Show Supplier Material materials with Manganese of 1.1 - 1.4 % | |
Phosphorus | 0.025 % Show Supplier Material materials with Phosphorus of 0.025 % | max. |
Silicon | 0.15 - 0.35 % Show Supplier Material materials with Silicon of 0.15 - 0.35 % | |
Sulfur | 0.008 % Show Supplier Material materials with Sulfur of 0.008 % | max. |
Titanium | 0.02 - 0.06 % Show Supplier Material materials with Titanium of 0.02 - 0.06 % |
Technological properties
| Property | ||
|---|---|---|
| Application areas | Quenchable boron steel is used in applications requiring good wear resistant properties. The main applications for these steel grades after heat treatment are agricultural machinery (discs, plough shares), machinery for public works and mining, cutting equipment, tubes for automotive safety parts etc. A popular application for untreated steel is concrete mixer drums. | |
| Chemical composition | This grade receives a globularisation treatment of the manganese sulphides. The efficiency of boron is ensured by the addition of elements that bind nitrogen. | |
| Delivery condtion | In spite of their moderate hardness and mechanical properties, boron grades exhibit remarkably good abrasion resistance in their delivery condition, thanks to their composite microstructure consisting of a hard pearlite phase embedded in ferrite. They are therefore very cost-effective solutions for applications requiring good abrasion resistance. | |
| Heat Treatment | The recommended austenitising temperature is 880°C. The temperature at the beginning of the quenching process (i.e. at the maximum cooling rate) is 750°C. Ac3 temperature is 860°C, for a heating rate of 5°C/s. Ac1 temperature is 750°C, and Ms (Martensitic Start) starting temperature is 400°C. In a tensile test, after austenitisation for 5 minutes at 850°C followed by water quenching, the structure of the sample obtained is entirely of the martensite type. In the same test performed at 840°C, a few islands of residual ferrite can be observed, regularly distributed. After heat treatment Its extreme hardness after heat treatment makes this grade particularly suitable for applications requiring high wear/abrasion resistance. Its use allows significant weight saving (up to 50% compared with an HSLA grade) in structural and automotive components. The specific advantage of ArcelorMittal quenchable boron steels is their suitability for water quenching, making the process more environmentally friendly (less effluent treatment) than that used for conventional carbon steels. Their hardening performance is excellent with both liquid and gas quenching. | |
| Other | Fatigue resistance is determined after heat treatment and quenching. Durabor® 22MnB5 steel 2.65 mm thick has been fatigue-tested by cyclical tensile loading with a load ratio of Rs = 0.1 after different heat treatments. Specimens were austenitised at 950°C for 5 minutes. The fatigue resistance of ArcelorMittal's boron quenchable steels is between 40 and 60% higher than S355MC AM FCE low alloy grade. It can be reduced by over 30% if total decarburisation is carried out. | |
| Processing methods | Forming This grade can be hot or cold formed. | |
| Surface condition | This boron grade is available in A unexposed surface quality only. | |