Does anyone know how to measure thermal conductivity? I have found this website https://www.linseis.com/en/our-produ...-conductivity/

I want to measure thermal conductivity of copper to find out if it makes a difference in welding.

 

You don't have to measure thermal conductivity of a material. It is a material property. You can google thermal conductivity for various materials to compare.
​​​​​​Common metals ranked by thermal conductivityRank
Metal Thermal Conductivity [BTU/(hr·ft⋅°F)]1
Copper 2232
Aluminum 1183
Brass 644
Steel 175
Bronze 15

Table didn't cut and paste so well...