Charakterisierung, Modellierung und Simulation des thermo-mechanischen Ermüdungsverhaltens von CuCo2Be

Research output: ThesisMaster's Thesis

Abstract

Cyclic loading of metallic engineering components at constant and elevated or fluctuating temperature causes a complex evolution of damage which can hardly be described in a unique and straightforward manner. In many engineering components thermo-mechanical loading can occur, e.g. cooling components in metallurgy, cylinder heads, etc. The steady rise of specific power and productivity leads to higher operating temperatures within the materials. At the same time the thermal expansion is restricted in some regions, due to the complex geometry of the components. Therefore, mechanical stresses occur and the cyclic plastic deformation leads to the thermo-mechanical fatigue (TMF) of the material. A careful analysis and comparison of the experimental results, based on a systematically variation of the relevant influence factors allow to develop empirical models for computing the fatigue life of thermo-mechanically loaded Cu-components. At specific low cycle fatigue (LCF) and out-of-phase thermo-mechanical fatigue (OP-TMF) test series at the copper alloy CuCo2Be are investigated by means of the cyclic deformation and lifetime behaviour. Based on stress-strain loops from LCF tests at different temperatures and ageing conditions a nonlinear combined material model is adopted to describe the cyclic deformation behaviour. The simulated loading parameters of stress and strain are the basis for the subsequent lifetime simulation based on a derived damage parameter.

Details

Translated title of the contributionCharacterisation, modelling and simulation of thermo-mechanical fatigue on CuCo2Be
Original languageGerman
Supervisors/Advisors
Award date15 Dec 2006
Publication statusPublished - 2006