Abstract
An effective way to improve the efficiency of a cryocooler is to improve the efficiency of the regenerator. In general, the heat capacity of materials decreases as temperature decreases. Thus, when temperature is below 40 K, lead or bismuth spheres are often used as regenerator materials. However, the pressure drop in a sphere regenerator is much larger than that in a screen regenerator. To overcome this dilemma, new low pressure loss metal-plated screens are proposed. A comparison test was performed with a two-stage GM cryocooler by replacing part of the first stage regenerator material, phosphorus bronze screens, with metal-plated screens. Compared to a regenerator filled with bronze screens, the cooling capacity of the first stage increased significantly at 30~40 K with these metal-plated screens. The detailed experimental results are reported in this paper.
