Page 413 - Handbook of Materials Failure Analysis

CHAPTER

Degradation of protective

PVD coatings 16

Alicja K. Krella
Institute of Fluid Flow Machinery, Polish Academy of Sciences, Gdansk, Poland

CHAPTER OUTLINE
1 Introduction ..................................................................................................... 411
2 Influence of Deposition Parameters on PVD Coating Properties ........................... 413
3 Deformation of Monolayer Coatings ................................................................... 419
4 Properties of Multi-Layer Coatings ..................................................................... 421
5 Deformation of Multi-Layer Coatings .................................................................. 424
6 Fatigue Strength of PVD Coating ........................................................................ 427
7 Degradation Caused by Dynamic Loading (Erosion) ............................................. 430
8 Conclusion ....................................................................................................... 433
References ............................................................................................................ 434

1 INTRODUCTION
Nowadays, coatings obtained by physical vapor deposition (PVD) have been widely
used to improve performance of construction or mechanical elements, extend service
life of tools, especially high-speed cutting tools due to their excellent tribological
properties and high hardness, and increase service life of blades in gas turbines
due to their high wear and oxidation resistance.
In previous review papers [1–6], PVD coatings were discussed mainly in aspects
in using on cutting tools (Table 16.1). Also, very deep studies about crystallographic
structure were performed [3]. However, there was lack of studies about deformation
mechanisms, fatigue, and erosion resistance of PVD coatings.
Due to the size of grains in PVD coatings (in most cases below 100 nm), PVD coat-
ings are classified as nanostructured materials [1,7]. Properties of PVD coatings are
mainly influenced by their chemical composition, structure (grain size and shape,
defects density, coating density), and residual stresses that depend on method and
parameters of deposition. PVD coatings possess compressive stresses that influence
their properties: high hardness, high elastic modulus, and high fracture strength
[1,8–20]. They also have high oxidation resistance and low friction coefficient [21,22].

Handbook of Materials Failure Analysis With Case Studies from the Chemicals, Concrete, and Power Industries. 411
http://dx.doi.org/10.1016/B978-0-08-100116-5.00016-8
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