ISO INTERNATIONAL STANDARD 10345-1 First edition 1992-05-01 Glass - Determination of stress-optical coefficient - Part 1: Tensile test Verre -- Determination du coefficient photo-élastique -- Partie 1: Essai de traction Reference number ISO10345-1:1992(E) ISO10345-1:1992(E) Foreword Iso (the International Organization for Standardization) is a worldwide federation of national standards bodies (isO member bodies).The work of preparing International Standards is normally carried out through iso technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, govern- mental and non-governmental, in liaison with iso, also take part in the work. Iso collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. Draft Internationai Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an Inter- national Standard requires approval by at least 75% of the member bodies casting a vote. mittee ISO/TC 48, Laboratory glassware and related apparatus, Sub- Committeesc5,Qualityofglassware Iso 10345 consists of the following parts, under the general title Glass --Determination of stress-optical coefficient: Part 1: Tensile test Part 2: Bending test AnnexAof thispartofIsO10345isfor informationonly ISO 1992 or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the publisher International Organizationfor Standardization Case Postale 56· CH-1211 Geneve 20: Switzerland Printed in Switzerland ii INTERNATIONAL STANDARD ISO 10345-1:1992(E) Glass - Determination of stress-optical coefficient Part 1: Tensile test Scope NOTE 2 The stress-optical coefficient can also be de- 1 termined by a compressive test if bend stress and shear This part of IsO 10345 describes the tensile test for stress are sufficiently insignificant (see 4.2 and 6.3). The direction of the testing force is then opposite to that of the determining the stress-optical coefficient of isotropic tensile test and the compensator shall be applied after glass. The stress-optical coefficient is a character- being turned through 90°. istic value of materials and it is necessary for de- termining the stress from the results Jo measurement of stress birefringence. 4 Apparatus 2 Definition 4.1 Device for measuring the height of the test specimen, to the nearest 0.01 mm. For the purposes of this part of iso 10345, the fol- lowing definition applies. 4.2 Apparatus, consisting of stressing equipment 2.1 stress-optical coefficient: Ratio of birefringence including force measuring device and polarization effect to applied uniaxial stress on an optical ma- measuring equipment with compensator. terial. [IsO 9802[1] The stressing equipment shall allow the application As K = of an uniaxial tensile load to the vertically arranged a test specimen across the measuring area (see fig- where ure 1). The test specimen shall not be loaded simul- taneously by shearing and bending. The force is the stress-optical coefficient; measuring device shall be capable of determining the testing forces to an accuracy of 1 %. The design △.s is the optical path difference; of the stressing equipment and test specimen hold- ing device shall allow the tensile axis to be aligned a is the light path in the test specimen with the axis of the test specimen during the test. (which is identical with the breadth b of the test specimen): The polarization measuring equipment shall allow the measurement of the optical path difference with a is the tensile or compressive stress. the compensator to 5 nm. The light source shall be white light with a corresponding interference filter NOTE1 The stress-optical coefficient is a function of the for the wavelength of 589.3 nm. wavelength. It can be either positive or negative. The stress