ISO 4897:1985

Cellular plastics — Determination of the coefficient of linear thermal expansion of rigid materials at sub-ambient temperatures

Specifies two methods for determing the coefficient of linear thermal expansion. Method A is the preferred method, it gives a value on a large sample at a chosen temperature. Method B should be employed to obtain an average coefficient for the temperature interval between the cryogenic temperature and the ambient temperature. In an annex the test apparatures for both methods are described in detail.