Creep crack growth testing of plastics - II. Data acquisition, data reduction and experimental results

To perform fracture mechanical tests under long-term static loading conditions at varying temperatures and in different environments, several test systems and a test procedure were developed and implemented. The test systems consist of a loading unit for a wide range of load levels and specimen geometries, an environmental chamber, the equipment for temperature control and devices for the measurement of crack lengths and crack opening displacements. A unique feature of these test systems is that crack growth and creep behaviour under static loads for a wide range of materials can be simultaneously characterised in one single test. While Part I of this paper describes the test system design and various test configurations, Part II is concerned with the data acquisition and reduction scheme and also provides experimental results of creep crack growth tests with plastics.