To be able to use the laser extensometer, the heating source must allow the laser to reach the test specimen. This rules out the usage of a radiation furnace since the slit that is needed for the extensometer will not give us a gas-thight chamber. Instead, we are using an induction system (5kW) with an induction coil placed around the gas chamber. Since we are doing fatigue testing and not tensile testing, the space between the coils are enough for the strain measurement. One big advantage with this system is the fast heating and cooling of the sample. Teknoheat AB designed and manufactured the coil for us so it could fit around our chamber.