| 释义 |
- References
- External links
Indentation force-deflection is a process used in the flexible foam manufacturing industry to assess the "softness" of a sample of foam such as memory foam. To conduct an IFD test, a circular flat indenter with a surface area of 323 square centimeters (50 sq. inches - 8" in diameter) is pressed against a foam sample usually 100 mm thick and with an area of 500 mm by 500 mm (ASTM standard D3574). The foam sample is first placed on a flat table perforated with holes to allow the passage of air. It is then "warmed up" by being compressed twice to 75% "strain", and then allowed to recover for six minutes. The force is measured 60 seconds after achieving 25% indentation with the indenter. Lower scores correspond with less firmness; higher scores with greater firmness.[1] US measurements are given in pounds-force, and European ones are given in newtons.[2]References1. ^{{cite book|author=Nigel Mills|title=Polymer Foams Handbook: Engineering and Biomechanics Applications and Design Guide|url=https://books.google.com/books?id=O4uNJjUT3ngC&pg=PA217|date=23 March 2007|publisher=Butterworth-Heinemann|isbn=978-0-08-047544-8|page=217}}
2. ^{{cite book|author1=Kurt C. Frisch|author2=Daniel Klempner|title=Advances in Urethane: Science & Technology|url=https://books.google.com/books?id=1obvdFeXZbAC&pg=PA10|date=6 August 1998|publisher=CRC |isbn=978-1-56676-675-3|page=10}}
External links- Joint Industry Foam Standards And Guidelines http://www.pfa.org/jifsg/jifsgs4.html
1 : ASTM standards |