How to select materials for springs working under high temperature

Metal springs intended for service at high temperatures must possess excellent resistance to relaxation, thermal stability, oxidation resistance, and a certain degree of corrosion resistance.

When the operating temperature of hardware springs is extremely high, the elastic modulus of the materials used to fabricate such hardware springs will decrease, which in turn reduces the load-bearing capacity and stiffness of the springs. Therefore, to ensure reliable performance under high-temperature operating conditions, it is necessary to determine its rate of change and calculate the impact of reduced load capacity on spring performance. Relevant regulations stipulate that the shear modulus of ordinary springs needs to be adjusted if their service temperature exceeds 60 degrees Celsius during operation.

When manufacturing springs from spring steel, the hardness of the spring shall be determined based on the magnitude of stress borne by the spring and its performance requirements. Nevertheless, planar strain fracture may occur as a result of improper hardness levels.

For springs installed in instruments or weighing scales, most manufacturers adopt constant elastic alloys. This material features an extremely low coefficient of thermal expansion variation, which enables the equipment to maintain measurement precision without being affected by temperature fluctuations.

In terms of material selection, attention shall be paid to the hardenability of steel, as this property bears a substantial correlation with the quality of the finished springs.