ISO 48-4-2018 pdf free.Rubber, vulcanized or thermoplastic – Determination ofhardness — Indentation hardness by durometermethod (Shore hardness).
This document specifies a method for determining the indentation hardness (Shore hardness) ofvulcanized or thermoplastic rubber using durometers with the following scales: the A scale for rubbers in the normal-hardness range; the D scale for rubbers in the high-hardness range; the A0 scale for rubbers in the low-hardness range and for cellular rubbers;- the AM scale for thin rubber test pieces in the normal-hardness range.
The following documents are referred to in the text in such a way that some or all of their contentconstitutes requirements of this document.For dated references, only the edition cited applies. Forundated references, the latest edition of the referenced document (including any amendments) applies.ISO 48-9,Rubber;vulcanized or thermoplastic – Determination of hardness — Part 9:Calibration andverification of hardness testers
ISo23529,Rubber — General procedures for preparing and conditioning test pieces for physical test methods
No terms and definitions are listed in this document.An indentor of specified dimensions is pressed into a test piece under a specified load and the depthof indentation measured.This indentation is converted to a hardness value by means of a specifiedrelation.
when using durometers, the scale should be chosen as follows:- for values less than 20 with a type D durometer: type A;—for values less than 20 with a type A durometer: type AO;-for values over 90 with a type A durometer: type D;
— for thin test pieces (less than 6 mm thick): type AM.These durometers consist of the components specified in 6.1.1 to 6.1.5.
The pressure foot for types A and D shall have a diameter of 18 mm  0,5 mm and a central hole ofdiameter 3 mm  0,1 mm.For type AO, the pressure foot shall have a minimum area of 500 mm2 with acentral hole of diameter 5,4 mm  0,2 mm.The tolerances on the dimension of the central hole and therequirement for the size of the pressure foot only apply to instruments used on a stand.
The indentor shall be formed from a hardened-steel rod of diameter 1,25 mm  0,15 mm to the shapeand dimensions shown in Figure 1 for type A durometers and Figure 2 for type D durometers. Type Aodurometers shall have a round indentor with a radius of 2,5 mm 0,02 mm in accordance with Figure 3.This is a device for allowing the extent of protrusion of the point of the indentor beyond the face of thepressure foot to be read.It shall be calibrated directly in terms of units ranging from O for the maximumprotrusion of 2,50 mm  0,02 mm to 100 for zero protrusion obtained by placing the pressure foot andindentor in firm contact with a suitable flat, hard surface (e.g.glass). ISO 48 pdf download.