For a long time, the shape and performance of the extension spring will change. If the extension spring is always in a certain situation, it may change its quality due to external conditions.Generally, there are the following situations:
I. wear of extension spring :
Wear can be divided into abrasive, fatigue and corrosion wear fracture.
Ii. Brittle fracture
The majority of spring break belongs to brittle fracture.Plastic fracture is possible only when the working temperature is high.In engineering, fatigue fracture, stress corrosion fracture and hydrogen embrittlement fracture are called brittle fracture.
Iii. extension spring fatigue fracture
Spring fracture under cyclic loading.
Iv. Hydrogen embrittlement, cadmium embrittlement and black embrittlement:
Brittle break due to high content of impurities in spring material.
V. corrosion fatigue fracture
Fracture of extension spring under combined cyclic load and corrosive medium.
Vi. Stress corrosion fracture
The fracture of extension spring is caused by the interaction of extension stress and corrosion medium.