The ability of mechanical parts and components to resist deformation. In the elastic range, stiffness is the proportionality factor of the part's load proportional to the displacement, that is, the force required to cause a unit displacement. Its reciprocal is called compliance, which is the displacement caused by unit force. Stiffness can be divided into static stiffness and dynamic stiffness.

Basic Definition: The stiffness (k) of a mechanism is the ability of an elastic body to resist deformation (bending, stretching, compression, etc.).
Calculation formula: k=P/δ P is the constant force acting on the mechanism, and δ is the deformation caused by the force.
The SI unit of stiffness is Newtons per meter (N/m).
Rotational stiffness Rotational stiffness (k) is: rubber-plastic pipe ring stiffness testing machine k=M/θ
where M is the applied moment and θ is the rotation angle. The national unit for rotational stiffness is Nm per radian.

Another common unit for rotational stiffness is inch pounds per degree. Other stiffnesses include: Tension and compression stiffness (Tensionand...
1. Static stiffness: refers to the ratio of the pressure (or tensile force) change of the shock-absorbing rubber to its displacement change within a certain displacement range. The measurement of static stiffness must be measured within a certain displacement range. The static stiffness values measured in the displacement range are different, but some manufacturers require the change curve of the entire displacement range measurement.

2. Dynamic stiffness: refers to the ratio of the change in pressure (or tensile force) to the change in displacement of the shock-absorbing rubber within a certain displacement range and at a certain frequency. The measurement of dynamic stiffness must be within a certain displacement range The dynamic stiffness value measured at a certain frequency is different in different displacement ranges and different frequencies.

3. Dynamic ratio: refers to the ratio of the dynamic stiffness to the static stiffness measured by the shock absorbing rubber within a certain displacement range.

4. Loss coefficient: During the stress process of the shock-absorbing rubber, there is a certain phase difference between the deformation of the rubber and the stress of the rubber, and the stress of the rubber is generally ahead of the deformation of the rubber by a certain phase angle δ. Usually the The loss coefficient is the tangent of the phase angle δ between the rubber stress and the rubber deformation, that is, the loss coefficient τ=tgδ.

5. Torsional stiffness: refers to the ratio between the torsion moment and the torsion angle of the shock absorbing rubber within a certain torsion angle range.

6. Durability: It refers to the number of vibrations when the shock-absorbing rubber is in a certain direction with a certain preload, amplitude, and vibration frequency, after n times of reciprocating vibration, the product is intact or the product is reciprocated until it is destroyed. Durability is a measure of the number of vibrations. Important indicators of safety performance and comprehensive performance of shock-absorbing rubber parts.
Methyl Phenyl vinyl silicone Gum MY 120