ASTM D7194-19(2024)

Anotace textu normy ASTM D7194-19(2024) :

This specification establishes the requirements for parts intended for aerospace use and machined from polychlorotrifluoroethylene (PCTFE) homopolymers. This specification, however, does not cover parts machined from PCTFE copolymer, PCTFE film or tape, or modified PCTFE. Material covered by this specification is on four types, differentiated based on intended uses and exposures: Types I (high service pressure) and II (low service pressure) for use in air and oxygen media, Type II for use in inert and reactive media, and Type IV for use in other media. The parts shall be manufactured from virgin, unplasticized, pure PCTFE homopolymer, and the use of recycled polymer or regrind shall be prohibited. The base material shall be free of defects and contaminants. The finished parts shall be white or gray in color with a natural translucent appearance, and shall be free of voids, scratches, fissures, inclusions, or entrapped air bubbles. Tests for specific gravity, melting point, tensile strength and elongation, deformation under load, zero strength time, mechanical impact (in ambient liquid oxygen and pressurized liquid and gaseous oxygen environments), and dimensional stability shall be performed and shall conform to the requirements specified.


Keywords:
annealing, dimensional stability, finished parts, PCTFE, polychlorotrifluoroethylene,, ICS Number Code 49.025.40 (Rubber and plastics),49.140 (Space systems and operations)