AISI 1045 steel is a widely used medium-carbon, high-quality carbon structural steel under the AISI/ASTM standard system.
AISI 1045 steel is a versatile medium-carbon steel known for its balanced strength, toughness, and machinability. It offers good forging properties and can be effectively heat-treated to meet specific mechanical requirements.
Supported by mature production processes and strong cost-effectiveness, it is widely used to manufacture durable, medium-load components such as shafts, gears, and connecting rods, making it a fundamental material in machinery manufacturing and equipment industries.
AISI 1045 STEEL & EQUIVALENT GRADE CHEMICAL COMPOSITION
| Grade | C | Si | Mn | P | S | Cr |
| 1045 | 0.43-0.50 | 0.15-0.35 | 0.60-0.90 | ≤0.04 | ≤0.05 | - |
| 45# | 0.42-0.50 | 0.17-0.37 | 0.50-0.80 | ≤0.035 | ≤0.035 | ≤0.25 |
| C45 | 0.42-0.50 | ≤0.4 | 0.50-0.90 | ≤0.03 | ≤0.035 | ≤0.4 |
| S45C | 0.42-0.48 | 0.15-0.35 | 0.60-0.90 | ≤0.03 | ≤0.035 | - |
AISI 1045 STEEL PHYSICAL PROPERTY
| Density, g/cm3 | 7.85 |
| Melting point °C | 1430-1450 |
| Poisson's ratio | 0.29-0.30 |
| Modulus of Elasticity, Gpa | 190-210 |
| Linear expansion coefficient (20-100℃) | 11.7×10⁻⁶ /℃ |
| Thermal conductivity W/(m.K) | 48-51 |
| Specific heat capacity (20℃),J/(kg・K) | Approx. 460 |
| Resistivity,Ω・m | 0.15-0.18 |
AISI 1045 STEEL FORGING
As a medium-carbon structural steel, AISI 1045 steel has good hot forging properties and strong deformation capacity. The core points of its forging process are as follows:
| Preheating | Initial forging temperature | Final forging temperature | Forging ratio | Cooling method |
| 600-700°C | 1100-1200°C | ≥800℃ | ≥4:1 | Slow cooling |
It should be noted here that 1045 steel can be air-cooled when necessary to achieve a certain effect of refining the grains, but it should never be cooled rapidly.
AISI 1045 STEEL HEAT TREATMENT
To achieve the desired strength, hardness, toughness, and wear resistance, AISI 1045 steel can be processed using various heat treatment techniques.
- AISI 1045 Steel Normalizing
The normalizing process for AISI 1045 steel focuses on improving its microstructure and strength. It can be used as a pretreatment process before quenching and tempering, or as the final heat treatment process for parts with low performance requirements.Therefore, normalizing is widely used in 1045 steel.
| Temperature | Cooling method | Process time | Microstructure | Grain size |
| 850-880°C | Air cooling | 2-3 days | Fine pearlite+ferrite | 6-8 |
AISI 1045+N Mechanical Property
| Tensile Strength | Yield Strength | Elongation | Reduction of Area | Impact Charpy-V | Hardness |
| 670-720 Mpa | ≥340 Mpa | 15-18% | 45-50% | ≥50 J | 170-240 HBW |
- AISI 1045 Steel Annealing
The annealing process for AISI 1045 steel focuses on reducing hardness to facilitate machining.It mainly includes soften annealing and stress-relief annealing.
| Soften Annealing | Stress-relief Annealing |
| 780-820°C | 550-650°C |
The difference between the two is that stress-relief annealing does not change the original microstructure and hardness, while soften annealing gives 1045 steel a coarse lamellar pearlite and ferrite microstructure, with a hardness of less than 200 HBW.
- AISI 1045 Steel Quenching & Tempering
This is the core heat treatment process for 1045 steel, the purpose of which is to obtain good comprehensive mechanical properties.
| AISI 1045 Quenching Process | |||
| Temperature | Cooling method | Microstructure | Hardness |
| 830-850°C | Water cooling | Martensite+Retained Austenite | 55-60HRC |
Tempering should be performed as soon as possible after quenching!
AISI 1045 steel can be adjusted according to the tempering temperature to obtain the required strength, hardness, and toughness.
| High-temperature tempering | Medium temperature tempering | Low-temperature tempering |
| 550-650℃ | 350-500℃ | 150-250℃ |
| 20-30HRC | 33-38HRC | 55-60HRC |
| High-performance parts | Elastic parts | High wear-resistant parts |
AISI 1045+QT Mechanical Property
| Section Size mm | ≤ 16 | 17 - 40 | 41 - 100 |
| Tensile Strength Mpa | 700-850 | 650-800 | 630-780 |
| Yield Strength Mpa | ≥ 500 | ≥430 | ≥ 370 |
| Elongation % | ≥ 14 | ≥ 16 | ≥ 17 |
| Impact Charpy J | ≥ 30 | ≥ 30 | ≥ 30 |
| Hardness HB | 210-245 | 195-235 | 185-230 |
AISI 1045 STEEL SUPPLY FORM & SIZE & TOLERANCE
If you are in search of premium AISI 1045 steel for your business operations, FUHONG stands as your ideal partner. We rank among China’s leading suppliers, with a dedicated focus on delivering high-quality, dependable and efficient 1045 steel products. No production challenge is insurmountable with our advanced processing technology, which is engineered to fulfill all your production demands.
Contact us today to explore our core 1045 steel solutions, and let FUHONG assist you in upgrading your products and enhancing your market competitiveness.
AISI 1045 steel Supplier,Stockist and Exporter,supplied with Round,Square,Flat,Block,and Shaft etc.
Hot Forged Round bar:Φ80-Φ1500mm
Hot Rolled Round bar:Φ14-Φ350mm
Hot Forged Square bar: Max Thickness:500mm
Flat bar/Blcoks:Thickness :120-800mm ,Width:120-1500mm
| Surface Finish | Black-Forged | Black-Rolled | Rough Turned | Cold Drawn | Peeled | Polished | Grinded |
| Tolerance | 0/+5mm | 0/+1mm | 0/+3mm | Best H11 | Best H9 | Best H9 | Best h8 |
Heat treatment:Quenched and Tempered (+QT), Normalizing (+N), Annealing (+A)
