Plastics — Determination of scratch properties

This document specifies a method for determining the scratch properties of plastics under defined conditions. The method defined in this document is used to investigate the behaviour of specified types of specimens under the scratch conditions defined and for classifying the type of scratch of specimens within the limitations inherent in the test conditions. It can also be used to determine comparative data for different types of material by means of a so-called scratch map in which the types of scratch behaviour for each set of test conditions of test load and test speed are determined using the basic method of constant-load testing, and also by means of the so-called critical normal load determined using an alternative method of linearly increasing load testing. The method is suitable for use with the following range of materials. — thermoplastic moulding, extrusion and casting materials, including filled and reinforced compounds in addition to unfilled types; — thermosetting moulding materials, including filled and reinforced compounds; — thermosetting sheets, rigid thermoplastic moulding and extrusion materials, including filled and reinforced compounds in addition to unfilled types. The method specifies the preferred dimensions for the test specimen and the preferred scratch-tip geometry.