A method has been developed that enables reliable predictions due to creep by thermomechanical loading. The method is based on the use of numerical stress-strain simulations and a generalised time-temperature parameter to determine the durability of the standard specimen due to creep. The method for predicting the durability due to creep, in addition to the existing method for predicting the durability due to fatigue, enables a complete durability prediction of a thermomechanically loaded product. The generalised time-temperature parameter has been designed so as to combine the features of basic time-temperature parameters. Its applicability is not limited to any particular crystalline materials and this has been shown on a substantial set of creep-rupture data from a variety of metals. A limited number of standard creep-rupture tests at high temperatures and high stresses are shown here to give satisfactory predictions of the durability due to creep at lower stresses or lower temperatures. Coefficients of the generalised time-temperature parameter are uniquely determined by using a simple, fast, robust and numerically stable algorithm.
D.09 Tutoring for postgraduate students
COBISS.SI-ID: 12497947OPC is software for estimation of optimal parameters for the Norton’s law of viscoplasticity. The user can select which test the parameters will be extracted from. Three steps are necessary to transcript a vast number of test data into an organised copy with temperature dependent material parameters. An arbitrary number of creep, relaxation or TMF tests can be considered for the parameter estimation. OPC is based on an input text file. Test data can be simply copied to the input file as obtained on the test rig. They do not have to be filtered. An efficient Savitzky-Golay filter ensures a smooth transition of test observations. The output consists of temperature dependent viscoplastic parameters k, K and N. They are given in the output text file.
F.06 Development of a new product
COBISS.SI-ID: 12563227The work was done on editing and prepration for printing of the proceedings from the conference and exhibition: Innovative Automotive Technology - IAT 2012.
C.01 Editorial board of a foreign/international collection of papers/book
COBISS.SI-ID: 12275227On 31st March 2012 a six-month guest-professor period of assoc.prof. Jernej Klemenc at Technical University of Kaiserslautern has ended. The objective of his work at TU Kaiserslautern was to give lectures in a German language for Machine Elements 1 course in a winter semester of the 2nd year university study. In parallel to the lectures the objective was to build, implement and test a self-test quation bank for Machine elements 1 lectures at TU Kaiserslautern. Assoc.prof. Jernej Klemenc successfully completed the lectures at Machine element 1 course and with a help of his co-workers at MEGT chair of TU Kaiserslautern composed the German and English versions of the self-test question bank. This question bank was then successfully implemented to the OLAT, a web portal of TU Kaiserslautern. It was tested by the students in parallel to the lectures. Due to the very good response an additional self-test question bank for Machine Elements 2 course was built an implemented.
B.05 Guest lecturer at an institute/university
COBISS.SI-ID: 12260123Member of the programme group were memebers of a R&D team for development of a flexible machining center CIMAT (for CIMOS d.d. company). The task of the programme group members was a strength optimisation of the machine with an objective of reducing its deformations due to the operating loads and increasing the eigen-frequencies of the machining center. In the year 2012 a prototype of the flexible machining center was built according to the technical drawings of the optimised load-carrying structure.
F.08 Development and manufacture of a prototype
COBISS.SI-ID: 12577563