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Briefly understand the performance of square tube?

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Do you know what the square tube has? Let's learn about it together with Xiaobian!!!

1. Plasticity

Plasticity refers to the ability of metal materials to produce plastic deformation (permanent deformation) without damage under load.

2. Hardness

Hardness is the indicator to measure the hardness and softness of metal materials. At present, the most commonly used method to determine the hardness in production is the indentation hardness method. It uses a certain geometric shape of the indenter to press into the surface of the tested metal material under a certain load, and then determines the hardness value according to the degree of indentation.


The common methods are Brinell hardness (HB), Rockwell hardness (HRA, HRB, HRC) and Vickers hardness (HV).

3. Fatigue

The strength, plasticity and hardness discussed above are the mechanical properties of metals under static load. In fact, many machine parts work under the cyclic load, under which the parts will produce fatigue.

4. Impact toughness

The load acting on the machine parts with high speed is called impact load, and the ability of metal to resist damage under impact load is called impact toughness.

5. Strength

Strength refers to the ability of metal materials to resist failure (excessive plastic deformation or fracture) under static load. Because the action mode of load has the form of tension, compression, bending, shear, so the strength is also divided into tensile strength, compressive strength, bending strength, shear strength and so on. There is a certain relationship between various strengths, and tensile strength is usually used as the most basic strength indicator in use.

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