Alloy steel is a type of steel with alloying elements other than carbon added to improve its properties. Some of the common additions to alloy steel include: chromium, cobalt, columbium, molybdenum, manganese, nickel, titanium, tungsten, silicon, and vanadium. Alloy steels are known for their enhanced properties compared to plain-carbon steel, such as: corrosion resistance, hardness, strength, wear resistance, and toughness. Alloy steels are used to make fabrication tooling and end products across just about all industries. The exact grade and composition of the alloy steel can be tailored to the requirements of the application.
The application of alloy steel is very wide and depends on the type of alloy steel. Some alloy steels are used to manufacture pipes, particularly those for energy-related uses. While others are utilized in the production of corrosion-resistant containers, silverware, pots, pans, and heating components for toasters and other kitchen equipment. Alloy steels can be divided into two primary categories: low-alloy steels and high-alloy steels. The application of alloy steels is mainly determined by the category that they fall in. Low-alloy steels are employed in a variety of industrial sectors due to their strength, machinability, and affordability. They can be found in ships, pipelines, pressure vessels, oil drilling platforms, military vehicles, and construction equipment. High-alloy steels, on the other hand, can be expensive to produce and challenging to work with. However, they are perfect for automotive applications, chemical processing, and power generation equipment due to their high strength, toughness, and corrosion resistance.
Grade | Composition | Hardness (HB) | Tensile Strength (MPa) | Yield Strength (MPa) | Elongation (%) |
---|---|---|---|---|---|
EN19 | C: 0.35-0.45, Mn: 0.50-0.80, Cr: 0.90-1.50 | 230-280 | 850-1000 | 625-700 | 12-15 |
EN36C | C: 0.15-0.25, Mn: 0.60-0.90, Cr: 1.30-1.70 | 290-350 | 900-1100 | 650-800 | 10-14 |
AISI4140 | C: 0.38-0.43, Mn: 0.75-1.00, Cr: 0.80-1.10 | 200-300 | 850-1000 | 650-800 | 12-20 |
AISI4130 | C: 0.28-0.33, Mn: 0.40-0.60, Cr: 0.80-1.10 | 197-235 | 560-760 | 420-660 | 20-30 |
AISI4145H | C: 0.42-0.50, Mn: 0.75-1.00, Cr: 0.80-1.10 | 200-300 | 900-1100 | 750-950 | 10-15 |
AISI4340 | C: 0.38-0.43, Mn: 0.60-0.80, Cr: 0.70-0.90 | 190-240 | 980-1200 | 740-1000 | 12-20 |
16MnCr5 | C: 0.14-0.19, Mn: 1.00-1.30, Cr: 0.80-1.10 | 207-255 | 700-850 | 550-650 | 14-17 |
20MnCr5 | C: 0.17-0.22, Mn: 1.10-1.40, Cr: 0.80-1.10 | 207-255 | 700-850 | 550-650 | 14-17 |
Grade | Chemical Composition | Applications |
---|---|---|
EN24 | C: 0.36-0.44, Si: 0.10-0.35, Mn: 0.45-0.70, S: 0.040 max, P: 0.040 max, Cr: 1.00-1.40, Mo: 0.20-0.35, Ni: 1.30-1.70, V: 0.35 max | Gears, crankshafts, connecting rods, bolts, nuts, studs, shafts, and axles |
34CrNiMo8 | C: 0.30-0.38, Si: 0.40 max, Mn: 0.50-0.80, S: 0.035 max, P: 0.035 max, Cr: 1.30-1.70, Mo: 0.15-0.30, Ni: 1.30-1.70 | High-strength fasteners, gears, shafts, crankshafts, turbine rotors, and heavy-duty construction machinery components |
EN353 | C: 0.15-0.25, Si: 0.10-0.35, Mn: 0.60-0.90, S: 0.040 max, P: 0.040 max, Cr: 0.80-1.20, Ni: 1.30-1.70, Mo: 0.20-0.30, Co: 0.15-0.30 | Highly stressed components in automotive and aerospace industries |
SAE8620 | C: 0.18-0.23, Si: 0.15-0.35, Mn: 0.70-0.90, S: 0.040 max, P: 0.035 max, Cr: 0.40-0.60, Ni: 0.40-0.70, Mo: 0.15-0.25 | Gears, pinions, crankshafts, camshafts, and heavy-duty machine parts |
38XC | C: 0.35-0.43, Si: 0.17-0.37, Mn: 0.50-0.80, S: 0.035 max, P: 0.035 max, Cr: 0.70-1.00, Ni: 0.30-0.70, Mo: 0.15-0.25 | Gears, camshafts, crankshafts, and connecting rods |
20X2H4A | C: 0.17-0.23, Si: 0.17-0.37, Mn: 0.40-0.70, S: 0.025 max, P: 0.025 max, Cr: 1.50-1.80, Ni: 0.25-0.60, Mo: 0.15-0.25 | Gears, pinions, crankshafts, camshafts, and heavy-duty machine parts |