The performance of metal materials is generally divided into two types: process performance and use performance. The so -called process performance refers to the performance of the metal materials under the process of cold and thermal processing during the processing manufacturing process of mechanical parts. The quality of the metal material process determines the adaptability of it in the process of processing. Due to the different processing conditions, the required process performance is different, such as casting performance, weldability, forgedness, thermal treatment performance, cutting processability, etc. The so -called use performance refers to the performance of metal materials under the conditions of mechanical parts, which includes mechanical properties, physical properties, chemical properties, etc. The quality of metal materials uses the scope and life of its use.
In the mechanical manufacturing industry, general mechanical parts are used in room temperature, normal pressure and non -strong corrosive media, and each mechanical parts will bear the role of different loads during use. Metal materials resist destructive performance under the action of loads, called mechanical properties (or mechanical properties).
The mechanical properties of metal materials are the main basis for the design and material selection of parts. Different load properties (such as stretching, compression, twisting, impact, circulating load, etc.), the mechanical properties required for metal materials will also be different. Common mechanical properties include: strength, plasticity, hardness, impact toughness, multiple impact resistance and fatigue limit. The following will discuss various mechanical properties.
1. strength
The intensity refers to the performance of metal materials against destruction (excessive plastic deformation or break) under the action of static lotus. Because the load is stretched, compressed, bending, shear and other forms, the strength is also divided into tensile strength, compressive strength, bending strength, and shear strength. There is often a certain connection between various intensity. In use, the tensile strength is generally used as the most basic strength pointer.
2. Plasticity
Plasticity refers to the ability to produce plastic deformation (permanent deformation) without damage under the action of loading.
3. hardness
Hardness is a pointer to measure the soft and hard level of metal materials. At present, the most commonly used method of determining the hardness method in production is the pressure into the hardness method. It is pressed into the tested metal material surface under a certain load with a certain geometric shape, and its hardness value is determined according to the degree of compression.
Common methods include Bud's Hardness (HB), Louz Hardness (HRA, HRB, HRC) and Victoria Hard (HV).
4. fatigue
The intensity, plasticity, and hardness discussed earlier are the mechanical performance pointers of metals under the action of static load. In fact, many machine parts work under circular load, and parts will cause fatigue under this condition.
5. Toughness
The load on the load on the machine is called impact load at a high speed. The ability to resist destruction under the action of impact loads is called impact toughness.