The high-temperature molten carbonate fuel cell is an ultra-clean and highly efficient power generator.It is operated at ～ 550-650 ℃,which is considered optimal in facilitating fast fuel cell reaction kinetics,utilizing waste heat efficiently,and allowing use of commercial construction materials.Commercial MW-size (mega watt) power plants of FuelCell Energy products have already been deployed worldwide.Metallic hardware materials are extensively utilized and may experience high-temperature reducing and oxidizing atmospheres in the presence of molten alkali carbonate electrolyte.Material selections are founded on many decades of focused research and development and field experience.Results to date show that the baseline stack module materials meet 5-year life goal and BOP (balance of plant) construction materials meet 20-year life goal.Material durability is well understood,and solutions are available to further extend the durability.This paper will review hardware materials experience and development approaches that would further reduce cost and extend life.