Читать книгу Manual of Laboratory Testing Methods for Dental Restorative Materials - Paromita Mazumdar - Страница 14

Rupture under low tension characterizes fragile materials, susceptible to brittleness. In these cases, tensile strength is not indicated to evaluate material reaction, because of the low cohesive condition. An alternative method of tensile strength is calculated by compressive testing. It is a relatively simple and reproducible test. It is defined as diametral compression test for tension or indirect tension. Disk sample is necessary to conduct this test, where it is compressed diametrically introducing tensile stress in the material in the plane of the force application by the test. This is calculated by the formula: 2 P/π × D × T, where: P = load applied, D = diameter of the disk, T = thickness of the disk, π = constant [9, 10] (as shown in Figure 1.6).

Figure 1.6 Diametral compressive strength assessment.

Source: Cefaly [9], Cattani‐Lorente [10].