EXPERIMENTAL INVESTIGATION ON ELECTRIC FANS FOR DOMESTIC APPLIANCES: PRODUCT DEVELOPMENT AND RELIABILITY TESTS

摘要

This work was performed in cooperation with the Quality Assurance office of the FIME company of Fabbriano and involved the development and performance of accelerated life tests on their GR1165 product. There is growing interest in this type of test because, providing it is conducted and interpreted correctly, it succeeds in providing the same information as conventional life tests with a considerable saving of time - and consequently also of money - for the business concerned. In the first stage of this study, quality tests (HALT) were developed to define the failure mode in qualitative terms, disregarding the time to failure. These tests were performed on a limited number samples submitted to high levels of stress in order to establish whether the product passes or fails the test: this enabled us to identify likely failure modes as the level of stress was increased progressively to induce the failure of the weakest link in the product and then analyze it causes. Then accelerated life tests were performed considering temperature as the sole acceleration factor. The Weibull theory was used to analyze the data obtained, while a linear regression from the levels of overstress to the level of normal use was traced using the Arrhenius relations.