【国外标准】 Standard Specification for Polytetrafluoroethylene (PTFE) Resin Molded Sheet and Molded Basic Shapes

This specification establishes the requirements and test methods for the material, dimensions, and workmanship, and the physical and electrical properties of molded sheet manufactured from polytetrafluoroethylene (PTFE) resin molding materials and molded basic shapes made from resin molding and extrusion materials. The sheet or molded basic shape shall be made from unpigmented PTFE and shall be free from foreign matters. Each of the samples shall undergo visual and dimensional inspection to verify their compliance with the standard requirements. The specimens shall conform to the following physical and electrical property requirements: tensile strength; elongation; dielectric strength; specific gravity; porosity; and melting point. Examination for internal defects shall also be conducted to ensure that the specimens are free from microscopic cracks, voids, inclusions, and other surface defects that might affect the serviceability of the materials.1.1 This specification establishes requirements and methods of test for the material, dimensions, and workmanship, and the physical and electrical properties of molded sheet in minimum thicknesses of 0.794 mm (1/32 in.) manufactured from PTFE resin molding materials defined in Specification D4894.1.2 This specification also establishes requirements for molded basic shapes made from molding materials. This specification is for products 300 mm (12 in.) or less in a dimension parallel to and 12.7 mm (0.5 in.) or greater in the dimension perpendicular to the direction of the applied molding pressure.1.3 The values stated in SI units are to be regarded as the standard.1.4 The following precautionary caveat pertains only to the test method portion, Section 7, of this specification. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Special attention is called to 13.2, 13.3, 13.6, 13.8, and A1.NOTE 1: There is no known ISO equivalent to this standard.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.