Alloy Steel Grade 10.9 bolts are robust fasteners crafted from medium carbon alloy steel, which undergoes a quenching and tempering process to enhance their mechanical properties. According to ISO 898-1 standards, the “10.9” label indicates a minimum tensile strength of 1040 MPa and a yield strength of 940 MPa, making these bolts perfect for tough structural and mechanical tasks. You’ll find them in various industries, including automotive, construction, heavy machinery, and engineering, where they provide the high clamping force, durability, and resistance to stress and vibration that are crucial. Typically, Grade 10.9 bolts are used alongside high-strength nuts and washers to ensure a secure joint.
When it comes to their composition, Alloy Steel Grade 10.9 bolts contain carbon (around 0.25–0.55%), manganese (0.6–1.65%), and other alloying elements like chromium, molybdenum, or boron, depending on the manufacturer and intended use. These components enhance the bolts’ hardenability and toughness. After undergoing heat treatment, they boast impressive mechanical properties, including high tensile strength, good fatigue resistance, and moderate corrosion resistance—often improved with zinc plating or black oxide finishes. Their hardness usually falls between 32 to 39 HRC, and the heat treatment process also refines their grain structure, boosting their load-bearing capacity and consistency under dynamic loads.
| Grades | Grade 10.9 Bolt |
|---|---|
| Standard | ASTM A324, ASME SA324 |
| Size | Dia M 20 to 100 mm Inch 3/4“ to 3.1/2″ |
| finish | Zinc plated / Plain / Hot dip galvanised |
| Carbon Steel 10.9 | C | P | S | B |
|---|---|---|---|---|
| 0.20-0.55 | 0.025 | 0.025 | 0.003 |
| Grades | Size Range | PS [MPa] | YS (min) [MPa] | TS (min) [MPa] | Hardness [Rockwell] |
|---|---|---|---|---|---|
| Class 10.9 | 5–100 | 830 | 940 | 1040 | C33–39 |
| Class and Material | Nominal Size Range (mm) | Mechanical Properties | ||
|---|---|---|---|---|
| Proof Load (MPa) | Min. Yield Strength (MPa) | Min. Tensile Strength (MPa) | ||
| Class 10.9 Alloy steel, quenched and tempered | 5mm – 100mm | 830 | 940 | 1040 |
We provide products that come with both mill test certificates and third-party test certificates, ensuring the highest standards of quality and compliance.
B6 Jaxon Steel is a trusted manufacturer and supplier of high-quality Alloy Steel Gr 10.9 Bolts in Istanbul, Turkey. We specialize in premium steel products, including Alloy Steel, Carbon Steel, Mild Steel and Galvanized Steel, with a strong focus on Carbon Steel Sheet and Plates. Our extensive inventory also includes Pipes, Tubes, Flanges, Forged Fittings and Bars. Committed to fast delivery and exceptional customer service, we use only the finest raw materials to ensure superior strength, durability and performance for critical industrial applications. Contact us today for all your Alloy Steel Gr 10.9 Bolts needs!
You’ll often find Alloy Steel Grade 10.9 bolts in situations where structural integrity and high-stress performance are non-negotiable. In the automotive sector, they play a vital role in engine assemblies, suspension systems, and chassis connections. In construction, they’re essential for steel frameworks, bridges, and equipment mounting. These bolts are also utilized in manufacturing machinery, wind turbines, railway systems, and heavy-duty mechanical setups. Their impressive strength-to-weight ratio makes them a go-to choice for demanding applications.
Filiz Steel is a leading manufacturer, supplier and exporter of high-quality Carbon Steel, Alloy Steel, Mild Steel and Galvanized Steel products. Our extensive product range includes Pipes, Tubes, Flanges, Pipe Fittings, Forged Fittings, Sheets and Plates, catering to various industries in Istanbul, Turkey.
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