636-0924/01 – Degradation Processes of Structural Materials (DPKM)

Identify degradation processes and their causes Specify the basic laws that control the degradation processes Select t the suitable material with high resistivity of degradation process Ability to calculate the lifetime of components Establish a critical crack size for the selected types of materials and loading Set a limit for the characteristics of stress conditions

The lecture presents methods of evaluating degradation processes in structural materials. Attention is focused primarily on the analysis of microstructural conditions for the initiation of brittle and ductile fracture, fatigue damage, creep, corrosion damage, stress corrosion cracking, and basic mechanisms of wear on functional surfaces. This analysis is followed by an explanation of the influence of temperature, loading mode and environmental parameters on the initiation of limit states - leading to fracture and the loss of the basic material function, i.e. transfer of the stress-strain field. Methods for evaluating these degradation processes are applied to metals, ceramic materials, polymers and basic types of composite materials. Particular attention is focused on the influence of the size and shape of structural components on the initiation of limit states and methods for assessing the resistance of structural components exposed to the negative effects of degradation processes. The lecture concludes with a presentation of methods for risk estimation of structures – both during the design stage and as part of operational decision-making during service life.

J. ČADEK: Creep in metallic materials, Academia Praha 1988, 376 s.