Standard Test Methods for Flexural Properties of Unreinforced and Reinforced Plastics and Electrical Insulating Materials
|Publication Date:||1 April 2010|
|ICS Code (Plastics and rubber insulating materials):||29.035.20|
These methods cover the determination of flexural properties of plastics and electrical insulating materials in the form of rectangular bars molded directly or cut from sheets, plates, or molded shapes. These methods are generally applicable to rigid and semirigid materials. However, flexural strength cannot be determined for those materials that do not break or that do not fail in the outer fibers. Two methods of test are described as follows:
Method I - A three-point loading system utilizing center loading on a simply supported beam.
Method II - A four-point loading system utilizing two load points equally spaced from their adjacent support points, with a distance between load points of one third of the support span.
Either method can be used with the two procedures which follow:
Procedure A, designed principally for materials that break at comparatively small deflections.
Procedure B, designed particularly for those materials that undergo large deflections during testing.
Comparative tests may be run according to either method or procedure, provided that method or procedure is found satisfactory for the material being tested.
NOTE 1 - The values stated in SI units are to be regarded as the standard.