Mechanical properties are the characteristics of materials under loading conditions, widely used in engineering design, manufacturing, and quality control. In order to ensure the safety and reliability of materials or components in actual application, systematic mechanical property testing must be carried out. Common mechanical properties include strength, hardness, plasticity, toughness, fatigue life, etc.



Mechanical property testing is usually divided into two major categories: destructive testing and non-destructive testing. Among them, destructive testing mainly includes tensile testing, compression testing, bending testing, impact testing, and fatigue testing; while non-destructive testing includes ultrasonic testing, magnetic particle testing, and penetrant testing, mainly used for detecting internal defects of materials without affecting their service performance.



1. Tensile Test



Tensile test is the most basic and commonly used mechanical property testing method. By holding the specimen in a tensile testing machine and applying an axial tensile force until the specimen breaks, important parameters such as yield strength, tensile strength, and elongation of the material can be obtained during the test. The stress-strain curve is a key basis for analyzing the mechanical behavior of materials.



2. Hardness Test

　　Hardness refers to the ability of a material's surface to resist local plastic deformation. Common testing methods include Brinell hardness, Rockwell hardness, and Vickers hardness. Different testing methods are suitable for different types of materials, such as metals, plastics, or ceramics. Hardness testing is simple to operate, the results are intuitive, and it is a commonly used detection method in production sites.

　　3. Impact Test



Impact test is used to evaluate the toughness and brittleness tendency of materials under impact loads. Common test methods include Charpy impact test and Izod impact test. By determining the impact absorbed work, it is possible to judge the fracture tendency of materials under low temperature or high stress conditions.



4. Fatigue Test



Many mechanical components work under alternating loads for a long time, which are prone to fatigue failure. Fatigue tests simulate actual working conditions by applying periodic loads, determining the life or fatigue limit of materials or components under a certain number of cycles.



With the development of technology, modern mechanical property testing is gradually developing towards automation and digitization. Advanced equipment such as computer-controlled universal testing machines and digital image correlation technology (DIC) have greatly improved testing accuracy and efficiency.

　　In summary, mechanical property testing is an indispensable part of material science and engineering applications. Through scientific testing methods, it is possible to comprehensively evaluate the behavior of materials under different loading conditions, providing a strong guarantee for product design and quality control.