The tensile strength of a metal, which is a material property, refers to its ability to withstand a pulling or stretching force without breaking or deforming permanently. Tensile strength is typically measured in units of pressure, such as pounds per square inch (psi) in the United States, or megapascals (MPa) in the metric system. The specific tensile strength of a metal varies depending on the type of metal or alloy in question.
Approximate tensile strength values for 6 common metals
- Steel (various types): Tensile strengths can range from approximately 30,000 psi (207 MPa) for mild steel to over 200,000 psi (1,380 MPa) for high-strength steel alloys.
- Aluminum (various alloys): Tensile strengths vary but typically range from 13,000 psi (90 MPa) for softer aluminum alloys to over 80,000 psi (550 MPa) for high-strength aluminum alloys like 7075.
- Copper: Tensile strength for pure copper is about 25,000 psi (172 MPa), but this can vary depending on the alloy.
- Titanium: Tensile strength for titanium alloys typically ranges from 40,000 psi (276 MPa) to 200,000 psi (1,380 MPa), depending on the specific alloy and heat treatment.
- Brass (various types): Tensile strength varies with the type of brass, with values ranging from 50,000 psi (345 MPa) to 68,000 psi (470 MPa) for common brass alloys.
- Nickel: Tensile strength for pure nickel is around 30,000 psi (207 MPa), but nickel-based alloys can have significantly higher tensile strengths.
Note: Mild steel = 55 ksi = 55,000 psi (some people use 60 ksi for easier calculation)
How to use this tensile strength of metals information for bending aluminum or stainless steel
Divide 55 ksi by the tensile strength number associated with the type of aluminum or stainless steel you use (the answer will be >1 for aluminum and <1 for stainless steel). Multiply the answer by the mild steel capacity of your machine to get the corresponding capacity of the machine. Be sure to adjust the settings of your machine for the actual metal thickness you are bending. Extra room for a radius is required when bending with a hand brake or hydraulic leaf brake.
The tensile strength of metals, such as aluminum or stainless steel, is a critical factor to consider when bending these materials. It provides valuable information that helps ensure safe and effective bending processes.
Here’s how you can use tensile strength information for bending aluminum or stainless steel:
Determine the specific alloy and temper of the aluminum or stainless steel you plan to bend. This information can be found in material specifications or data sheets.
Consider the intended application and environmental factors, as they may influence the choice of material. For example, if corrosion resistance is a priority, you might opt for a stainless steel alloy with excellent resistance properties.
Review the tensile strength of the selected material to ensure it is suitable for the bending application.
Make sure the material’s tensile strength exceeds the anticipated forces and stresses that will be applied during the bending process. This helps prevent material failure.
Bending Equipment and Techniques
Choose the appropriate bending equipment and technique based on the material’s tensile strength. Different materials may require specific equipment or methods to achieve successful bends.
For aluminum with lower tensile strength, simpler bending techniques or tools like a bench vise may suffice. For stainless steel with higher tensile strength, you may need specialized equipment like a hydraulic press brake or roll bender.
Bend Radius and Angle
When designing the bend, take into account the material’s tensile strength and its ability to withstand bending without failure.
Ensure that the bend radius and angle do not exceed the material’s bending capacity. For materials with high tensile strength, this may require larger bending radii or less aggressive bend angles.
Especially for materials with high tensile strength, avoid over-bending, which can cause stress concentrations and material failure.
Utilize gradual bending techniques and proper tools to ensure that the material remains within its elastic deformation range and does not exceed its tensile strength.
After bending, inspect the material for any signs of deformation, cracking, or other defects. Ensure the bent part meets the required specifications.
Depending on the specific project, you may need to perform additional processes such as cutting, welding, or surface finishing to complete the bent part.
Keep records of the material specifications, the bending process, and any quality control checks performed. This documentation can be valuable for traceability and quality assurance.
In summary, the tensile strength of aluminum or stainless steel is a critical parameter for safe and effective bending. It helps determine the material’s suitability for the intended application, guides the selection of appropriate bending equipment and techniques, and ensures that the bending process stays within the material’s mechanical limits. By considering tensile strength along with other material properties, you can achieve precise and reliable bends in these metals.
Tensile Strengths of Stainless Steel
The tensile strength of stainless steel can vary depending on the specific grade and heat treatment (temper) of the stainless steel. Stainless steel is a family of alloys that includes a wide range of compositions, each designed for different applications. Tensile strength is typically measured in units of pressure, such as pounds per square inch (psi) in the United States or megapascals (MPa) in the metric system.
Here are approximate tensile strength values for some common stainless steel grades:
- Austenitic Stainless Steel (e.g., 304 and 316): Tensile strengths typically range from 75,000 psi (515 MPa) to 90,000 psi (620 MPa).
- Ferritic Stainless Steel (e.g., 430): Tensile strengths generally range from 50,000 psi (345 MPa) to 75,000 psi (515 MPa).
- Martensitic Stainless Steel (e.g., 410): Tensile strengths can vary but typically fall in the range of 70,000 psi (480 MPa) to 160,000 psi (1,100 MPa) for higher-strength martensitic stainless steels.
- Duplex Stainless Steel (e.g., 2205): Tensile strengths typically range from 80,000 psi (550 MPa) to 116,000 psi (800 MPa).
- Precipitation-Hardening Stainless Steel (e.g., 17-4 PH): Tensile strengths can vary but generally fall in the range of 160,000 psi (1,100 MPa) to 190,000 psi (1,310 MPa).
It’s important to note that the specific tensile strength of stainless steel can vary based on factors such as the alloy composition, heat treatment, and manufacturing process. Tensile strength is a key mechanical property of stainless steel and plays a significant role in determining its suitability for various applications. For precise tensile strength values for a particular stainless steel grade, it’s advisable to refer to material data sheets or manufacturer specifications.
Stainless steel tensile strength table
|ASTM / AISI Grade||SAE Number||Material||Tensile Strength Ksi|
|304||30304||Annealed Bar Sheet/Plate||80/90 75 min|
|316||30316||Annealed Bar Sheet/Plate||75/90 75 min|
|316L||30316L||Sheet/Plate Annealed Bar||70 min 80/90|
|321||30321||Sheet||75 min 100 max|
|440F Se||51440F Se||Annealed Bar||100/120|
|630 (17 -4) C||____||Cond-A-Bar Cond-H900 Bar Cond-H1025 Bar||150200170|
Tensile strength of aluminum
The tensile strength of aluminum can vary depending on the specific alloy and temper (heat treatment) of the aluminum. Here are some approximate tensile strength values for commonly used aluminum alloys:
- Aluminum 1100: Tensile strength of approximately 13,000 psi (90 MPa).
- Aluminum 2024: Tensile strength of around 68,000 psi (470 MPa).
- Aluminum 3003: Tensile strength of about 20,000 psi (140 MPa).
- Aluminum 5052: Tensile strength of roughly 33,000 psi (230 MPa).
- Aluminum 6061: Tensile strength of approximately 45,000 psi (310 MPa).
- Aluminum 6063: Tensile strength of around 27,000 psi (185 MPa).
- Aluminum 7075: Tensile strength of about 83,000 psi (570 MPa).
These values are approximate and can vary based on factors such as the specific temper of the alloy, the manufacturing process, and any heat treatments applied. Tensile strength is an important property of aluminum as it indicates its ability to withstand axial loads or forces when subjected to tension. It’s important to consult specific material data sheets or manufacturer specifications for precise tensile strength values for your particular aluminum alloy and temper.
May be slightly magnetic when cold worked Not stocked-typical properties. 1 ksi = 1000 psi
Aluminum tensile strength table
|Alloy and Temper||Tensile Strength3 (ksi)|
|Alclad 2024- T4,-T351||64|
|Alclad 2024- T81,-T85||65|
|Alclad 3004- H32||31|
|Alclad 3004- H34||35|
|Alclad 3004- H36||38|
|Alclad 3004- H38||41|
|Cast Tool And Jig Plates||26|
- Tempers T361 and T861 were formerly designated T36 and T86, respectively.
- For stress-relieved tempers, the characteristics and properties other than
those specified may differ somewhat from the corresponding characteristics
and properties of the material in the basic temper.
- 1 ksi = 1000 psi
- Minimum Properties
Conversion chart that converts sheet metal gauge numbers into the metal thickness
|26 gauge||24 ga.||22 ga.||20 ga .||18 ga.||16 ga.||14 ga.||13 ga.||12 ga.||11 ga.||10 ga.||9 ga.||8 ga.||7 ga.||6 ga.|
Click for a Bend Radius Chart for aluminum and stainless steel for recommended minimum bend radii.