SAE 1045 Steel Precision Engineering Workhorse
High-quality medium carbon steel optimized for exceptional machinability and superior response to induction hardening. Available in bars, plates, and custom cut sizes.
SAE 1045 Technical Standards
At SS Alloy Steel, we ensure every batch of SAE 1045 meets or exceeds international benchmarks for chemical consistency and mechanical integrity.
| Standard | Equivalent Grade |
|---|---|
| USA (ASTM/AISI) | SAE 1045 / AISI 1045 |
| Germany (DIN) | C45 / 1.1191 / CK45 |
| Japan (JIS) | S45C |
| UK (BS) | EN8 / 080M40 |
| China (GB) | 45# Steel |
| Carbon (C) | Manganese (Mn) | Silicon (Si) | P (Max) | S (Max) |
|---|---|---|---|---|
| 0.43 - 0.50 | 0.60 - 0.90 | 0.15 - 0.35 | 0.040 | 0.050 |
| Tensile Strength (MPa) | Yield Strength (MPa) | Elongation (%) | Reduction of Area (%) | Hardness (HB) |
|---|---|---|---|---|
| ≥ 570 | ≥ 310 | ≥ 16 | ≥ 40 | 170 - 210 |
Choose Your Finish: Hot Rolled vs. Cold Drawn
The delivery condition of SAE 1045 steel significantly impacts your machining time, tool wear, and final product cost. Use our guide to select the right fit for your project.
Hot Rolled (HR) 1045
- Surface: Rough finish with protective black oxide scale.
- Tolerances: Standard mill tolerances; requires more machining allowance.
- Internal Stress: Low internal stress, minimal distortion after heavy cutting.
- Applications: Large gears, forged blocks, and heavy structural shafts.
Cold Drawn (CD) 1045
- Surface: Bright, smooth, and scale-free "shiny" finish.
- Tolerances: Tight dimensional accuracy; often used "as-is" for diameter.
- Mechanicals: Higher yield strength and hardness than hot rolled bars.
- Applications: Precision bolts, hydraulic shafts, and high-speed CNC parts.
Visualizing the surface difference between HR (left) and CD (right) 1045 steel bars.
Why AISI 1045 is the Preferred Choice
Beyond standard specifications, SAE 1045 offers a unique combination of processability and post-hardening performance that alloy steels often cannot match at this price point.
High Machinability
Rated at 70% of AISI 1212. This allows for higher spindle speeds and longer tool life, significantly reducing your part-to-part production costs.
Hardening Versatility
Perfect for localized induction or flame hardening. Achieve high wear resistance (up to HRC 60) on critical surfaces while maintaining a tough, ductile core.
Reliable Toughness
Excellent impact resistance when normalized. It provides the structural integrity required for axles, pins, and connecting rods under cyclic loading.
Optimized Heat Treatment Processes
At SS Alloy Steel, we control the thermal cycle to unlock the full potential of your 1045 steel components. Whether you need a soft annealed state for complex forging or a Quenched & Tempered state for high strength.
- Normalizing: 850°C - 880°C. Refines grain structure and improves uniformity.
- Annealing: 800°C - 850°C. Achieve max machinability for heavy CNC milling.
- Hardening: 820°C - 860°C. Water or oil quench depending on section size.
- Tempering: 400°C - 650°C. Tailors final hardness and impact strength.
Typical hardness profile after surface induction hardening.
Available Dimensions & Formats
SS Alloy Steel maintains a massive inventory of SAE 1045. From heavy forged blocks to precision cold-drawn bars, we have the size you need, ready for immediate dispatch.
Round Bars
Diameter: 10mm - 800mm
Steel Plates
Thickness: 6mm - 500mm
Hexagonal
Size: 12mm - 100mm
Hollow Bars
OD: 30mm - 500mm
| Product Type | Size Range | Tolerance | Delivery State |
|---|---|---|---|
| Cold Drawn Round Bar | Φ 10 - Φ 100 mm | h9, h10, h11 | Bright / Polished |
| Hot Rolled Round Bar | Φ 16 - Φ 320 mm | ASTM A29 | Black / Peeled |
| Forged Round Bar | Φ 320 - Φ 850 mm | -0/+5mm | Rough Turned |
| Hot Rolled Plate | T: 8 - 500 mm | En 10029 | As Rolled / Flame Cut |
Engineered for High-Stress Environments
SAE 1045 is the versatile workhorse of the engineering world. From automotive drivetrains to heavy industrial machinery, its balanced properties ensure reliability where it matters most.
Automotive Systems
AISI 1045 is the preferred choice for components requiring a balance of strength and fatigue resistance. It is widely used for parts that undergo induction hardening for localized wear resistance.
Industrial Machinery
Ideal for general-purpose mechanical parts that require higher strength than mild steel. 1045 provides the necessary toughness for transmission and structural support.
Agri-Construction
The excellent weldability and machinability make SAE 1045 a standard for construction fasteners and agricultural tool attachments where field durability is critical.
One-Stop Fabrication Excellence
Eliminate the need for multiple vendors. SS Alloy Steel provides integrated processing services to deliver "Ready-to-Assemble" SAE 1045 components.
Cutting & Boring
High-speed band sawing and deep-hole boring for SAE 1045 round bars and plates. We achieve tight tolerances (+/- 1mm) and can convert solid bars into custom heavy-wall hollow sections to your specs.
Grinding & Peeling
Ensure perfect surface integrity and dimensional precision. We offer centerless grinding and surface peeling to remove decarburization, delivering bright-finish bars with h9, h10, or h11 tolerances.
Heat Treatment
Optimize your components' mechanical properties with our advanced thermal cycles. We provide Stress Relieving, Normalizing, and full Quenched & Tempered (Q+T) services to meet your specific hardness requirements.
Custom Parts Made to Blueprint
Skip the rough machining. Send us your technical drawings for a complete fabrication quote.
Buying & Technical FAQ
Quick answers to the most common questions about SAE 1045 steel procurement, heat treatment, and fabrication.