Stochastic Method for Extrapolation of Diagrams of Long-Term Strength of Structural Materials
Journal Title: Технічна механіка, Техническая механика, Technical Mechanics - Year 2017, Vol 2, Issue 2
Abstract
The research objective is to develop a stochastic method of basic diagrams for extrapolation of a long-term strength of structural materials to the lives exceeded the experiment duration by several orders. This method takes into account a random character of a long-term strength of materials and considers a hypothetic stress value as a totally analogue random quantity for a chosen life. Physically, it results in a gross correctness in comparison with the known deterministic methods, and the research novelty. Based on stochastic processing the long-term strength diagrams and methods of a regression analysis, the technique for identifying the unknown parameters of the method is developed. It was concluded that the theoretical results, obtained with this method, are in a good agreement with the long-strength experiments with samples made from the 18Cr-8Ni stainless steel. The above method can be used to predict the failure time of several structural materials that are widely employed for ma-chine-building, nuclear engineering and rocket technology, as well as in the development of standards, methodic recommendations for evaluating the structural materials lives in creep.
Authors and Affiliations
I. Doyar
Keywords
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