Meaning
Dissipative energy conversion occurs when viscoelastic materials are subjected to repetitive cyclic mechanical deformation. This hysteretic heating is the process by which mechanical energy lost during each load cycle is converted directly into thermal energy, raising the internal temperature of the material. Elongated polymers or rubber compounds used in vehicle tires, flexible couplings, and industrial shock absorbers are particularly prone to this phenomenon.
The localized temperature rise can accelerate material degradation, reduce mechanical stiffness, or cause thermal runaway, leading to premature component failure under normal operating conditions.
Energy Loss
Cyclic stress-strain curves for viscoelastomers show a characteristic loop representing the energy dissipated per cycle. Under conditions of hysteretic heating, this lost energy accumulate as heat faster than it can be conducted away from the core of the part. This balance depends on the frequency of the loading cycles.
Higher frequencies generate more heat per unit time.
Product Warranty
Supply contracts for industrial dampening mounts often include performance warranties linked to operating temperature limits. Manufacturers must test for hysteretic heating to ensure that the rubber components do not degrade under continuous heavy vibration. If a supplier fails to account for this heat buildup, premature warranty claims can occur.
These claims can severely damage the financial viability of a supply contract.
Operational Boundary
Design engineers can mitigate this thermal risk by selecting materials with lower loss tangents or by optimizing the geometry to improve heat dissipation. When hysteretic heating is controlled, the elastomeric component maintains its stiffness and damping properties over a long service life. This performance is critical for the reliable operation of heavy machinery and automotive suspension systems.
