【Abstract】 This paper describes the design principle and test results of a two-stage G-M refrigerator with lowest refrigerating temperature of 3.0K and cooling capacity of 0.5W and 4.3W at 4.2K and 10.0K respectively. The main points of the successful development of this prototype are following:1. Using ErNi2 as regenerator matrix in second stage.2. Properly designing the structure of 2-stage regenerator according to the results of the numerical calculation.3. Properly designing the structure of the heat exchanger in cold head after carefullyanalysizing it.更多还原