Thermal Conductivity Measurement of Mesoscale Lattices Using Steady-State Infrared Thermography

Ultralight architected materials are favorable for thermal insulation purposes in gas turbines, hypersonic, electronic packaging, and aerospace applications. The effective mechanical properties and thermal conductivity of these structures can be engineered via their architectural configurations, making them an excellent candidate to meet requirements of these applications. Advanced manufacturing has paved the path for fabrication of these structures, reaching the properties that is beyond the material space capacity. Among all architected materials, ultralight hollow nickel lattices by exhibiting 99.9% porosity and complete recoverability after compression above 50% strain have appeared very promising. The challenge for reporting accurate data on the thermal conductivity of these structures is performing a non-contact measurement methodology. Here, we designed a new IR thermography-based setup for thermal conductivity measurement of mesoscale cellular materials. The effective thermal conductivity of two hollow doped nickel samples with volume fraction of 0.09% and two different surface finishes (rough and polished) is measured as a function of compressive force and temperature. Surface properties is proposed as a new control knob for changing the effective thermal properties in the architected materials.