By Genesis Infante, PhD
In HVAC engineering, heat management isn’t just about moving air, it’s about moving energy efficiently and predictably. Components like heat spreaders ensure that heat is transferred precisely where needed, whether in heat exchangers, condenser units, or high-efficiency air handlers.
Aluminum and aluminum alloys are well-known for their high thermal conductivity, low weight, and cost-effectiveness; they’re a staple in thermal management designs [1], [2], [3]. But here’s a critical point many overlook: the “book value” of aluminum’s thermal conductivity may not match the actual performance of the aluminum you’re using.
Why HVAC Metallurgists and Materials Engineers Test Instead of Trust
There are good reasons to measure thermal conductivity directly, even with well-known materials such as aluminum, rather than relying solely on reference data or supplier specifications:
- Changing Suppliers: Different suppliers may use different processing techniques, heat treatments, or purity levels. These can alter thermal performance enough to impact heat transfer efficiency [4], [5].
- Uncertainty of Alloy Variation: Even small additions of alloying elements can significantly reduce thermal conductivity. If the actual composition drifts from what’s expected, system performance can suffer [6].
- Batch-to-Batch Consistency: For critical applications, confirming that each batch meets the same thermal performance ensures consistent product quality.
- Aging or Oxidation Effects: Stored stock or reused materials may have surface oxidation or contamination, which can change thermal transfer properties [7].
- Verification for Compliance: Meeting internal QA standards or external certification requirements often requires actual test data, not just a datasheet.
For HVAC systems with tight thermal margins, the difference between 200 W/mK and 220 W/mK can translate into real-world efficiency gains or losses.
The TAL Advantage: C-Therm Trident Accuracy and Precision
At Thermal Analysis Labs (TAL), we use the C-Therm Trident™ Thermal Conductivity System equipped with the Transient Plane Source (TPS) Slab Utility, a method proven to deliver the best combination of accuracy and precision for thin, highly conductive materials like aluminum foil and conforming to ISO 22007-2.
In one application highlight, 99.9% pure aluminum foil (0.13 mm thick) was cut into 75 mm × 75 mm squares, pressed for flatness, and sandwiched around the TPS sensor with expanded polystyrene insulation. This setup ensured minimal heat loss and maximum accuracy.
The result? Thermal conductivity measurements within 1% of the known reference value for aluminum, a level of agreement that underscores the method’s capability and our lab’s expertise.
Read more about this application highlight here!
How this Testing Strengthens HVAC Innovation
Accurate thermal conductivity testing allows HVAC material specialists to:
- Validate new suppliers or materials before scaling up production.
- Confirm alloy consistency for long-term performance reliability.
- Feed accurate material data into simulation models for better predictive design.
- Reduce costly prototype iterations caused by incorrect thermal assumptions.
By combining advanced equipment with experienced thermal scientists, TAL delivers data that HVAC engineers and materials specialists can trust for high-stakes design decisions.
Interested in Verifying your Aluminum’s Thermal Performance?
In HVAC system design, understanding the thermal conductivity of aluminum components is key to optimizing heat transfer and system efficiency. C-Therm’s Trident Thermal Conductivity Platform delivers precise, application-relevant data to support your engineering decisions.
Request a Quote for Thermal Conductivity Testing Services
Our Thermal Analysis Labs (TAL) team offers expert contract testing tailored to HVAC applications and aluminum materials.
Contact us at info@thermalanalysislabs.com
Tel: +1 (506) 457-1515
References
[1] Li, Y.; Zhang, A., Materials 2023, 16, 2972. Thermal Conductivity of Aluminum Alloys—A Review. doi: 10.3390/ma16082972
[2] Davis, J.R. Aluminum and Aluminum Alloys; ASM International: Materials Park, OH, USA, 2001
[3] Lumley, R. Fundamentals of Aluminium Metallurgy: Production, Processing and Applications; Woodhead Publishing: Oxford, UK, 2011.
[4] Hatch, J.E. Aluminum: Properties and Physical Metallurgy; ASM International: Metals Park, OH, USA, 1984.
[5] Lumley, R.N.; O’Donnell, R.G.; Gunasegaram, D.R.; Givord, M. Heat Treatment of High-Pressure Die Castings. Metall. Mater. Trans. A 2007, 38, 2564–2574
[6] Gan, J.Q.; Du, J.; Wen, C.; Zhang, G.G.; Shi, M.B.; Yuan, Z.Z. The Effect of Fe Content on the Solidification Pathway, Microstructure and Thermal Conductivity of Hypoeutectic Al–Si Alloys. Int. J. Met. 2022, 16, 178–190.
[7] Kim, Y.M.; Choi, S.W.; Kim, Y.C.; Kang, C.S. Increasing the Thermal Diffusivity of Al–Si–Mg Alloys by Heat Treatment. J. Therm. Anal. Calorim. 2022, 147, 2139–2146
About the Author
Genesis Infante is the Laboratory Services Manager at C-Therm. He has extensive experience in thermal analysis and materials characterization from his previous position as a Materials Scientist at C-Therm. He holds a Ph.D. in Organic Chemistry from the University of New Brunswick.