What resistance comes from the interface?
Interface resistance assessment
Performance Testing · Thermal Analysis
Interfacial Thermal Resistance and Conductance
Evaluate resistance to heat flow across a material interface. Agree the contact surfaces, specimen geometry, temperature and loading conditions before comparing thermal resistance or conductance.
- Price
- from£181 per sample, excl. VATA £45 service fee applies to orders under £300, excluding VAT.
- Turnaround
- 8 working days Preparation and scope dependent
- Available platforms
- LW-9389
- Typical outputs
- Thermal resistance on an agreed basisDerived conductance where applicableMaterial or condition comparisonGeometry, loading and method notes
Why this service
What Interfacial Thermal Resistance and Conductance can help you understand
An interface can restrict heat transfer even when the adjoining materials conduct heat well. TESTDOG reviews the contact or layer structure and defines what the measurement can separate and report.
How do contact conditions affect heat flow?
Contact-condition comparison
Which interface material performs better?
Material or assembly comparison
Choose the scope
Start from the question, not the tool
The method, preparation route and reporting depth depend on what you need to decide.
Interface resistance assessment
What resistance comes from the interface?
- Best used when
- What resistance comes from the interface?
- Typical result
- Thermal resistance on an agreed basis
- Preparation note
- Agree surface preparation, mounting and contact conditions before testing.
Contact-condition comparison
How do contact conditions affect heat flow?
- Best used when
- How do contact conditions affect heat flow?
- Typical result
- Derived conductance where applicable
- Preparation note
- Confirm specimen geometry and whether bulk and contact contributions need separation.
Material or assembly comparison
Which interface material performs better?
- Best used when
- Which interface material performs better?
- Typical result
- Material or condition comparison
- Preparation note
- Thin-film boundaries may need a different route from macroscopic contact measurements.
Common outputs
A result package matched to the decision you need to make
Fields, conditions, processing and file formats are confirmed before work begins.
Thermal resistance on an agreed basis reported with the agreed units, sample reference and measurement conditions.
Derived conductance where applicable supplied in a labelled format suitable for direct sample or condition comparison.
Material or condition comparison provided with the processing basis and quality checks agreed during technical review.
Geometry, loading and method notes included when selected in the confirmed reporting scope.
Example results
What Interfacial Thermal Resistance and results can look like
The plot shows effect of modifier concentration on the thermal conductivity, electrical conductivity, viscosity, and FTIR spectra.
Yihua Qian et al. · source · CC BY
The plot shows dSC thermograms of Span65 and its physical state and thermal behavior when dispersed in different base fluids—SE.
Yihua Qian et al. · source · CC BYSample requirements
What to provide before work begins
Provide representative, clearly labelled samples and identify the decision, feature or comparison that matters.
| Suitable sample | Submission requirement | Planning note |
|---|---|---|
| Mating solid surfaces | Describe both materials, contact area, flatness, roughness and the intended assembly load. | Agree surface preparation, mounting and contact conditions before testing. |
| Thermal interface pads or sheets | Provide composition, thickness, contact dimensions and any compression or conditioning history. | Confirm specimen geometry and whether bulk and contact contributions need separation. |
| Layered specimens | Provide layer sequence, thicknesses, substrate and the interface of interest for feasibility review. | Thin-film boundaries may need a different route from macroscopic contact measurements. |
Objective: state the decision, comparison or acceptance criterion the work must support.
Handling and access: declare hazards, instability, confidentiality, file constraints or special logistics before dispatch or transfer.
Questions and answers
Common planning decisions
Short answers to issues that can change preparation, scope, timing or interpretation.
Is interface resistance the same as bulk conductivity?
No. Bulk conductivity describes heat transport within a material. Interface resistance concerns transfer across a boundary or contact; a whole-assembly measurement can contain both contributions.
Why are pressure and surface condition important?
For contacting surfaces, loading and surface condition can change effective contact and the measured resistance. Specify the assembly conditions that the test should represent.
Will I receive resistance or conductance?
Agree the required quantity and units before testing. Conductance is the reciprocal of resistance on the same area basis; the report identifies any area normalisation and derivation.
Can I request ASTM D5470?
Provide the standard and edition with your enquiry. ASTM D5470 addresses thermal transmission properties of relevant insulation materials; sample and method applicability require technical review.
Can a thin-film interface be measured?
Send the layer structure, thicknesses and substrate details for feasibility review. A thin-film boundary may require a different measurement route from a macroscopic contact or interface pad.
How long will it take?
Typical turnaround is 8 working days after sample acceptance and method confirmation.
Configure the service
Send the information needed to scope Interfacial Thermal Resistance and Conductance correctly
- Sample form, material, dimensions and quantity
- Feature or decision the result must address
- Required comparison, acceptance criterion or reference
- Preferred output and reporting depth
Interfacial Thermal Resistance and Conductancefrom£181
A £45 service fee applies to orders under £300, excluding VAT.
Typical turnaround: 8 working days
Configure & Book