Quantifying Long Term Sensor Drift Driven by Viscoelastic Strain Redistribution
Viscoelastic stress relaxation in packaging adhesives redistributes mounting strains over time, driving zero drift that requires thermal pre-aging to stabilize.
IEC 60068 Dry Heat
Thermal Compliance
International testing procedures evaluate the ability of equipment to withstand high temperatures without humidity control for specified durations. Compliance with iec 60068 dry heat ensures that instruments operate reliably in environments where moisture content is low but the thermal load is high.
Controlled Exposure
Specimen placement occurs in a chamber where the temperature is raised to a pre-defined level and maintained for a set period. In iec 60068 dry heat, the specimen is typically allowed to reach thermal equilibrium before the timing of the exposure starts. Different severity levels exist based on the intended use of the device, ranging from a few hours to several weeks of continuous heat.
Air circulation must be maintained to prevent the buildup of localized hot spots that would exceed the test requirements. Sensors monitor the surface temperature of the component to confirm that the internal heat dissipation does not lead to a thermal runaway.
Functional Check
Performance is assessed either during the exposure or immediately following the return to ambient conditions. Failure to meet the requirements of iec 60068 dry heat results in the rejection of the design for hot climate applications.
Performance Boundary
Qualification ends once the device demonstrates that its electrical and mechanical properties remain within the original tolerance. Any drift in the output signals during the iec 60068 dry heat test is logged as a potential reliability risk.