Yes, aluminum foil can partially block thermal imaging.
Aluminum foil exhibits reflective properties that can hinder the detection of thermal radiation. This makes it difficult for infrared cameras to accurately capture heat signals from objects covered or encased in foil.
The effectiveness of this blocking depends on the thickness of the foil, the material being inspected, and the sensitivity of the infrared camera.
However, professional thermal imaging cameras used in specific applications such as law enforcement or industrial inspections are designed to overcome interference caused by thin materials such as aluminum foil.