Abstract: Through the critical point corrosion temperature test, ferric chloride point corrosion test, metallographic test, tensile test, compared 2205 duplex stainless steel and the existing heat pump water heater water tank main application of stainless steel mechanical properties, corrosion resistance differences, 2205 duplex stainless steel has obvious advantages, can greatly improve the service life of heat pump water heater water tank, has a good application prospect. Through the experiments of molding processing performance and welding performance, it is found that the key problems need to be solved in the application of heat pump water heater water tank, and the solution is proposed through the process verification.

Key words: Heat pump water heater, Water tank, 2205 duplex stainless steel, Corrosion property