Thermo-mechanical tests on W7-X current lead flanges

•There are significant mechanical loads on the cryostat and radial flanges for W7-X current leads.•These are due to evacuation of W7-X cryostat, cool-down of cold mass, electro-magnetic forces and self weight of leads.•The actual mechanical loads were reduced to simplify the experimental set-up.•The tests were carried out on mock-up flanges test assembly at ambient temperature and at 77K.•The thermo-mechanical tests on W7-X current lead flanges validate the design and joints of these flanges to the leads.