Angle steel, commonly known as angle iron, is a long strip of steel with two sides perpendicular to each other, forming an angle. It belongs to the category of carbon structural steel for construction with a simple cross-section and is mainly used in structural applications such as metal components and factory frames. When used, it is required to have good weldability, plastic deformation capacity, and a certain mechanical strength.
Angle steel is mainly divided into two categories: equal-sided angle steel and unequal-sided angle steel. Equal-sided angle steel has two sides of equal width, while unequal-sided angle steel has two sides of different lengths. It can also be further divided into unequal-sided equal-thickness and unequal-sided unequal-thickness types.
Angle steel comes in many types of materials, ranging from the most common ordinary carbon steel to high-performance alloy steel.
| Material category | Commonly used brands | Core features | Applicable Scenarios |
| Carbon structural steel | Q235 series | Most commonly used and offers the best cost-performance ratio. It has excellent strength, ductility, and weldability. | It is suitable for general building structures, mechanical parts, and ordinary frames. Among them, Q235B is the most common grade. |
| Low alloy high strength steel | Q345 series (Q345B, C,etc.), Q355, Q390D, Q420D | It has higher strength and greater load-bearing capacity. Performance is improved by adding a small amount of alloying elements. | Used in structures with higher strength requirements, such as bridges, transmission towers, ships, and heavy machinery. |
| Stainless steel | 304、316、201、301、309S、430 | It has excellent corrosion resistance and a good appearance. | Suitable for humid, corrosive environments or occasions where appearance is important, such as outdoor facilities, medical devices, food processing equipment, decoration, etc. |
| High-quality carbon structural steel | 10#、20#、35#、45# | Different carbon contents result in different properties. Higher carbon content leads to higher strength and hardness, but lower plasticity and weldability. | It is often used to manufacture mechanical parts that require high strength or specific properties. |
| Alloy structural steel | 20Cr、40Cr、20CrMo、35CrMo、42CrMo、40CrNiMo | It has very high strength, hardness, wear resistance and toughness. | Used to manufacture critical components such as gears and shafts that bear high loads. |
| Spring steel | 65Mn、50Mn、50Cr | It has high elastic limit and fatigue strength. | It is specifically designed for manufacturing various springs, elastic elements, or structural components that require high elasticity. |
There are many standard sizes and specifications for angle steel, mainly divided into two categories: equal-sided angle steel and unequal-sided angle steel. Their dimensions are usually expressed as “side width × side width × side thickness” (unit: millimeters).
Equal Angle Steel
Standard size range: side width from 20mm × 20mm to 200mm × 200mm. According to national standards, specifications are usually expressed by model number (side width in centimeters), from 2# to 20#.
Small (side length < 5cm): 20×3, 25×3, 30×3, 40×4, 50×5, etc.
Medium (side length 5-12.5cm): 63×5, 70×6, 80×6, 90×8, 100×10, etc.
Large (side length > 12.5cm): 125×10, 140×12, 160×14, 180×16, 200×20, etc.
Unequal Angle Steel
An unequal angle steel has two sides of unequal width. Its dimensions are expressed as “long side width × short side width × side thickness”.
Standard size range: Long side width from 25mm to 200mm, short side width from 16mm to 125mm.
Common size examples:
25×16×3, 32×20×4
40×25×4, 50×32×4, 56×36×5
63×40×6, 70×45×5, 75×50×6
80×50×6, 90×56×6, 100×63×8
100×80×8, 125×80×8, 140×90×10
160×100×10, 180×110×12, 200×125×14
Our entire range of angle steel conforms to the GB/T 706-2016 national standard. We maintain a full stock of angle steel in sizes from 20-200mm and support custom cutting and galvanizing. We can quickly respond to orders for projects of all sizes, ensuring uninterrupted project progress. If you are interested, please feel free to contact us. We possess the professional knowledge and resources to provide high-quality products tailored to your specifications.
Post time: Aug-21-2026
