Izod Darbe Testi Cihazının Tasarımı ve Plastik Testlerinde Kullanılması

Abstract

Izod Impact Strength Test Device is a pendulum type instrument that measures the impact strength of a material. This instrument is imported since it is not produced in Turkey. An Instrument is designed, manufactured, assembled and used for plastic tests First, international standards such as ISO and ASTM are investigated. Conceptual design and detail design studies completed in according to these international standards. Designed parts of the instrument are manufactured using appropriate manufacturing techniques in Ankara. Other finished products such as bearing and encoder are purchased. Electronic system and software is prepared. All sub-parts assembled together and manufacturing process is completed. Geometric tolerances defined by standards are measured on the assembled product. Loses of friction and drag force are determined with the dynamic tests. Effects of these factors are added to software so that the device can automatically eliminate these effects. Reduced length of the pendulum is calculated which is explained in standards. This length is compared with real pendulum length and it is determined that these two values are proper. Different plastic materials are purchased. These bulk materials are processed and test specimens are manufactured according to ISO and ASTM standards. In addition, granules of different plastics are procured. Test specimens are produced via compression moulding device at Hacettepe University. Specimens are tested at Kocaeli University and BUTEKOM, which have calibrated Izod Impact Strength test instrument. Specimens are also tested at Hacettepe University with the test instrument that produced within this study. All the results are evaluated together and accuracy rate of the device for each test specimen is calculated. According to test results, it is observed that the results of the materials such as POM or PMMA which have less Izod impact strength are more accurate, since the test results of new instrument and calibrated instruments are very similar. It is also observed that the results of the materials such as PA6 or unnotched specimens, which have higher Izod impact strength are less accurate. It is concluded that usage of higher capacity pendulum is required for the strong materials.