Chapter 47 - Use of ceramic part in G-M refrigerator

Abstract

This chapter presents the application of toughening ZrO2 ceramics for wear part in G-M refrigerator. To increase the life span and reliability of refrigerator, ZrO2 ceramics have been applied to fabricate rotary unit, which is a wear part of G-M refrigerator. Engineering ceramics with their high hardness and wear resistance offer substantial advantages over metallic or polymeric materials. Toughening ZrO2 ceramics with their enhanced toughness appear to be ideal wear-resistance materials for wear part in G-M refrigerator. They can improve the lifetime and reliability of the refrigerator. The wear particles formed in Teflon-metal sliding and ZrO2-ZrO2 sliding respectively have been studied. The thickness of wear particles is estimated from analyses based on a model. The results show ZrO2 ceramics have the highest application potential for wear part in G-M refrigerator. Ceramics used most for wear-protection are dense or low-porous ZrO2 ceramics, and some other oxide-based ceramics. Among the ceramics used in industry at the present time, ZrO2 ceramics, and silicon carbide-based ceramics have the highest application potential. They demonstrate excellent wear-resistance and high mechanical properties. ZrO2-based materials are well documented for low thermal-conductivity, high fracture toughness, as well as offering excellent wear resistance in adverse environments.