Conceptual design of test devices for the JHR tailored to the needs of the nuclear fusion community

•Conceptual design of three devices to adapt the JHR for the needs of the fusion community.•Designs include a ceramic functional material device to measure static fatigue parameters and optical parameters.•Also included is a device to irradiate samples at cryogenic temperatures (∼50K).•The final design allows for investigation of thermos-mechanical fatigue during irradiation.