A novel and effective method for cryogenic milling of polytetrafluoroethylene

• DOI: 10.1007/s00170-020-06332-4
• Publication Date: 2020-11-27T14:02:39Z
• Authors: Yongquan Gan; Yongqing Wang; Kuo Liu; Lingsheng Han; Qi Luo; Haibo Liu
• Keywords: Molding (decorative); Gasket; Polytetrafluoroethylene

Polytetrafluoroethylene (PTFE) is a typical material widely used in bearing, gaskets, gears, etc. of many various fields such as aeronautics, astronautics, and military. Traditionally, PTFE is manufactured by molding process, which is suitable for processing of large quantities and standard parts. And a deburring treatment is necessary after molding. For small-scale or special shape products, molding techniques require new molds which need long time period. In contrast, machining method can meet the requirements more efficiently. However, the traditional machining is prone to produce machining defects such as edge fins and burrs. In this paper, a novel and effective method for cryogenic machining is proposed. According to the experiment results, the cryogenic machining can effectively restrain the production of machining defects and subsurface damage layer. And the mechanism of defect suppression in cryogenic machining is revealed by analyzing the change of molecular structure and properties with temperature.