Mechanics of Components with Treated or Coated Surfaces

Surface treatment is an efficient means for protection of various products against corrosion and also for increasing strength or resistance to wear or fatigue. Also certain electrical, chemical or optical properties may be achieved only by creating special surface layers. Many examples can be given: leaf springs with shot-peened surfaces; carburised and hardened tooth gears; coated cutting tips for machining; chemical appliances made of glass strengthened by ion exchange; enamelled vessels and containers; components for engines or turbines with heat insulating ceramic surface layers; chemical equipment made from low-carbon steel clad with a layer of stainless steel or other more expensive material; endoprostheses of hip joints with ceramic coatings; multilayered integrated circuits and other components for electronics and electrotechnology. In many of these components, high stresses often act; from mechanical loading as well as thermal and residual ones, caused by the surface treatment itself. These stresses can sometimes lead to a failure of parts bearing small or even no load. Thus, for an efficient utilisation of all the advantages surface treatment offers, and for assuring that the designed component will work reliably for a certain period, often under very severe conditions, it is necessary to know how components with coated or otherwise treated surfaces behave under mechanical loading, and what the reasons may be for their preliminary fracture or rejection from service. It is also important to know the general principles of design of surface treated components.

Klappentext

This book deals with the mechanical behaviour and fracture mechanics of parts with chemically, thermally or mechanically treated surfaces or with inorganic coatings (thin or thick), created in order to achieve special mechanical, chemical, thermal, electrical, magnetic or optical properties. The book explains how the strength or fatigue resistance are related to the parameters of surface treatment. The topic is not limited to one class of materials or surface treatment, but is dealt with in such a way that the information may be used for metallic and nonmetallic (e.g. ceramic) components and various kinds of treatment and their combinations, corresponding to modern design trends. Theoretical principles are explained and gives relatively simple formulae and methods (such as those for measuring mechanical and fracture mechanics properties) which can be used directly in research, design and development departments. Practical examples are also given.

Inhalt
1 Mechanisms of failure of structural materials.- 2 Increasing the strength and lifetime by surface treatment.- 3 Stresses in bodies with treated surfaces.- 4 Principles of fracture mechanics.- 5 Determination of mechanical properties.- 6 Determination of stresses and time to failure.- 7 Design and optimisation of surface treatment.- References and author index.