Elastic material is widely used in machinery and instrument manufacturing industry to make various parts and components. Its main functions in all kinds of machinery and instruments are as follows: absorbing vibration and impact energy through deformation, easing vibration and impact of machinery or parts; controlling the movement of machinery or parts by using the energy stored in its own deformation; and; Realize the functions of medium isolation, sealing and flexible shaft connection. The physical properties of elastic materials, such as elasticity, corrosion resistance, magnetic conductivity and conductivity, can also be used to make instruments and instrument components. The physical quantities such as pressure, tension and temperature can be converted into displacement so as to measure or control these physical quantities.
Classification of elastic materials
1.1 classification by chemical composition
Elastic materials can be divided into: carbon spring steel, alloy spring steel, stainless spring steel, iron-based elastic alloy, nickel based elastic alloy, cobalt based elastic alloy, etc.
1.2 classification by use characteristics
According to the service characteristics of elastic materials, they can be classified as follows:
1.2.1 general spring steel
(1) Deformation strengthening spring steel: carbon spring steel wire.
(2) Martensite strengthened spring steel: Oil quenched and tempered steel wire.
(3) Comprehensive strengthening spring steel: precipitation hardening stainless steel wire
1.2.2 elastic alloy
(1) Corrosion resistant high elastic alloy
(2) High temperature and high elasticity alloy
(3) Constant elastic alloy
(4) Elastic alloy with special mechanical and physical properties
2. Main performance indexes of spring steel and elastic alloy
2.1 elastic modulus
When the tension does not exceed a certain value, the deformation is directly proportional to the external force, which is usually called Hooke’s law. The formula is as follows:
Where ε – strain (deformation size)
σ – stress (external force)
E-tensile modulus of elasticity
The tensile modulus of elasticity (also known as young’s modulus of elasticity or elastic modulus) is an index to measure the degree of elastic deformation of metal materials. Different grades of elastic modulus are different, and the elastic modulus of the same brand is basically a constant.
In engineering, in addition to the elastic modulus (E) which represents the tensile deformation resistance of metals, the shear modulus of elasticity (g) is often used to express the shear deformation resistance of metals.