Spring is one of the important foundations in mechanical products. It is a lot of types, according to the shape of the division: coil spring, plate (piece) spring, disc spring, ring spring, plane (truncated cone) scroll spring, etc .; according to load characteristics are: compression, stretching, The
Spring stress are: bending stress, torsional stress, tensile stress and composite stress.
Spring failure modes are: fracture, deformation, relaxation, wear. One of the most important is the fracture and deformation (relaxation).
1. Brittle fracture: the most part of the spring fracture is brittle fracture. Only when the working temperature is high, it is possible to plastic fracture. In the project, fatigue fracture, stress corrosion fracture and hydrogen embrittlement fracture are called brittle fracture
2. Fatigue fracture: the fracture of the spring under cyclic loading.
3. Stress corrosion fracture: in the tensile stress and corrosive medium under the joint action caused by spring fracture phenomenon.
4. Corrosion fatigue fracture: spring in the cyclic load and corrosive medium under the joint action occurred in the fracture.
5. Hydrogen brittle, cadmium crisp, crisp: due to the spring material in the impurity content is too high caused by brittle fracture.
6. Wear: wear is divided into: abrasive, fatigue and corrosion wear fracture.