Summary of mechanical properties and experimental properties of materials

Summary of mechanical properties and experimental properties of materials

The mechanical properties of materials refer to the mechanical characteristics that materials exhibit when they bear various external loads (tension, compression, bending, torsion, impact, alternating stress, etc.) under different environments (temperature, medium, humidity). Tests for determining the characteristics of materials when they are subjected to force or energy under certain environmental conditions, also known as material mechanical properties tests. The test content mainly measures the strength, hardness, rigidity, plasticity and toughness of the material. Mechanical tests include: natural exposure test and manual simulation test (laboratory test). Manual simulation tests are usually carried out using instruments and equipment such as testing machines. The common methods for laboratory tests are as follows:
(1) Specify a mechanical movement. This is a widely used experimental method.
Mechanical performance tests can be divided into two categories: static tests and dynamic tests. Static tests include tensile tests, compression tests, bending tests, shear tests, torsion tests, hardness tests, stress relaxation tests, fracture toughness tests, etc. Dynamic tests include impact tests, fatigue tests (see Fatigue Strength), etc.
Mechanical performance tests are performed on various specific test machines. The test machine is divided into mechanical and hydraulic types according to the transmission method, and can be manually operated or automatically operated. Some test machines also have computer devices that automatically perform test operations and controls according to the compiled program, and can display the results with images and numbers to improve the accuracy of the test and make it easy to use.
1) Specify a mechanical motion close to the actual environment to simulate.
2) Define a mechanical movement according to the equivalent principle of damage or failure of the test product.

The characteristic of using a method of specifying a mechanical movement for the test is that when the tolerance requirements of each motion characteristic parameter are met, the test has high reproducibility.

(2) Specify a test machine, which is a test method derived from the equivalent principle of destruction or failure of the test sample.
The characteristic of the test method of the specified test machine is that the motion characteristic parameters need not be measured during the test, but in some cases the reproducibility is poor.

(3) Specify a structural response spectrum, which is mainly used in impact testing machines. The mechanical environmental tests specified in domestic and foreign mechanical environmental test methods standards are common: sinusoidal vibration test; random vibration test; impact test; collision test; centrifugal constant acceleration test; sway test; tilt and overturn test; bouncing test; impact test; free fall test, etc. Material testing machines that test yield strength are generally tested according to specific usage standards. This is stipulated in relevant industry standards or domestic and foreign standards. If there are no relevant standards, both the supply and demand parties in the material test need to customize the test method according to manual simulation test of the mechanical test, and be recognized by both the supply and demand parties as the basis.