Table Of ContentTRIBOLOGY
FUNDAMENTALS
AND ADVANCEMENTS
Edited by Jürgen Gegner
Tribology: Fundamentals and Advancements
Edited by Jürgen Gegner
Contributors
Maciej Paszkowski, Giuseppe Pintaude, Mohammad Tauviqirrahman, Rifky Ismail, J
Jamari, Dirk J. Schipper, Manfred Mauntz, Jürgen Gegner, Ulrich Kuipers, Stefan Klingauf,
Nehal Ahmed, Amal Nassar, Masataka Nosaka, Virginia Sáenz De Viteri, Elena Fuentes,
Remigiusz Michalczewski, Marek Kalbarczyk, Michal Pawel Michalak, Witold Piekoszewski,
Marian Szczerek, Waldemar Tuszynski, Jan Wulczyński, Xana Fernandez, Amaya Igartua,
Erik Kuhn, Walter Holweger
Copyright © 2016 Second Edition
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First published May, 2013 second - 2016
ISBN-10: 953-51-1135-3
ISBN-13: 978-953-51-1135-1
Contents
Preface VII
Section 1 Lubrication and Properties of Lubricants 1
Chapter 1 Fundamentals of Lubricants and Lubrication 3
Walter Holweger
Chapter 2 Lubrication and Lubricants 55
Nehal S. Ahmed and Amal M. Nassar
Chapter 3 Some Aspects of Grease Flow in Lubrication Systems and
Friction Nodes 77
Maciej Paszkowski
Section 2 Boundary Lubrication Applications 107
Chapter 4 Cryogenic Tribology in High-Speed Bearings and Shaft Seals of
Rocket Turbopumps 109
Masataka Nosaka and Takahisa Kato
Chapter 5 Titanium and Titanium Alloys as Biomaterials 155
Virginia Sáenz de Viteri and Elena Fuentes
Section 3 Testing and Modeling 183
Chapter 6 New Scuffing Test Methods for the Determination of the
Scuffing Resistance of Coated Gears 185
Remigiusz Michalczewski, Marek Kalbarczyk, Michal Michalak,
Witold Piekoszewski, Marian Szczerek, Waldemar Tuszynski and Jan
Wulczynski
VI Contents
Chapter 7 Introduction of the Ratio of the Hardness to the Reduced
Elastic Modulus for Abrasion 217
Giuseppe Pintaude
Chapter 8 Artificial Slip Surface: Potential Application in
Lubricated MEMS 231
M. Tauviqirrahman, R. Ismail, J. Jamari and D.J. Schipper
Chapter 9 Friction and Wear of a Grease Lubricated Contact — An
Energetic Approach 251
Erik Kuhn
Section 4 Sustainability of Tribosystems 273
Chapter 10 Innovative “Green” Tribological Solutions for Clean
Small Engines 275
Xana Fernández-Pérez, Amaya Igartua, Roman Nevshupa, Patricio
Zabala, Borja Zabala, Rolf Luther, Flavia Gili and Claudio Genovesio
Chapter 11 A Sensor System for Online Oil Condition Monitoring of
Operating Components 305
Manfred R. Mauntz, Jürgen Gegner, Ulrich Kuipers and Stefan
Klingau
Preface
As the subject of tribology comprises lubrication, friction and wear of contact components
highly relevant to practical applications, it challenges scientists from chemistry, physics and
materials engineering around the world on today’s sophisticated experimental and theoreti‐
cal foundation to complex interdisciplinary research. Recent results and developments are
preferably presented and evaluated in the context of established knowledge. Consisting of
eleven chapters divided into the four parts of Lubrication and Properties of Lubricants,
Boundary Lubrication Applications, Testing and Modeling, and Sustainability of Tribosys‐
tems, this textbook therefore merges basic concepts with new findings and approaches. Tri‐
bology – Fundamentals and Advancements, supported by competent authors, aims to
convey current research trends in the light of the state of the art to students, scientists and
practitioners and help them solve their problems.
The undesirable loss of energy and material by friction and wear cause damage amounting
to several ten billion dollars. The high economical relevance of the demand for durable
products has been driving the development and continuous refinement of the scientific and
engineering discipline of tribology since the middle of the last century.
The excellent invited Chapter 1 on Fundamentals of Lubricants and Lubrication opens the book
by providing an expert introduction to the chemistry and basic properties of oils, additives
and greases on the advanced level of a standard reference guide. The two following contri‐
butions complete the general background of the Part 1. Chapter 2 on Lubrication and Lubricat‐
ing Oil outlines the regimes of lubrication and deals with liquid, solid and gaseous
lubricants. Oils take up the most space of this paper. Chapter 3 on Some Aspects of Grease
Flow in Lubrication Systems and Friction Nodes extends the discussion of grease lubrication
and covers structural as well as rheologic properties.
Part 2 turns the reader’s attention to applications under adverse operating conditions. Chap‐
ter 4 on Cryogenic High-Speed Bearings and Shaft Seals of Rocket Turbopumps reviews promising
approaches for reliable machine elements in future space transportation systems. A crucial
material issue in aerospace engineering is associated with this task, for instance, due to the
differences in the thermal alteration of the mechanical behavior. The optional use of ceram‐
ics in hybrid bearings at extremely low service temperatures and boundary lubrication indi‐
cates the importance of innovative materials for tribologically loaded components. Chapter
5 on Titanium and Titanium Alloys as Biomaterials makes this conclusion even more meaning‐
ful and extents it to mixed friction oriented surface engineering. Recent attempts to increase
the wear resistance of orthopedic implants are discussed. Titanium and its alloys provide
excellent biocompatibility and corrosion protection but the poor tribological properties are
detrimental.
VIII Preface
Part 3 of the book is dedicated to laboratory testing, modeling approaches and mathematical
simulation. The New Scuffing Test Methods for the Determination of the Scuffing Resistance of
Coated Gears, proposed in Chapter 6, is applied to evaluate the performance of coatings. The
examination of new lubricants requires gear testing as well. The prediction of the abrasion
response of a tribosystem involves material characteristics of the counterbodies. It is an of‐
ten raised question what relationship holds between wear and hardness? Introducing the Ra‐
tio of the Hardness to the Reduced Elastic Modulus for Abrasion in Chapter 7 serves the purpose
of modeling the wear coefficient. The suitability is demonstrated on the examples of the
well-known tribosystems of glass‒bearing steel and alumina‒hard metal. The characteriza‐
tion of the cutting efficiency is particularly relevant to machining processes. Chapter 8, enti‐
tled Artificial Slip Surface: Potential Application in Lubricated MEMS, is another highlight of the
book. It presents a novel lubrication model for moving parts in micro electro-mechanical
systems, based on the numerical solution of a modified Reynolds equation, to improve the
tribological performance of lubricated contacts. Chapter 9 on Friction and Wear of a Grease
Lubricated Contact ‒ An Energetical Approach instructively specializes the discussion of Chap‐
ter 3. It elaborates an advanced energy balance model and includes rheometer tests. Grease
degradation is correlated with the energetics of a tribosystem.
Part 4 finally addresses the emerging sustainability topic from the two essential aspects of
environmentally friendly tribology and early failure detection. Chapter 10 on Innovative
“Green” Tribological Solutions for Clean Small Engines considers the practical problems with
biodegradable lubricants, such as abrasive wear, in this demanding operating environment.
It investigates new biofuel-compatible eco-oils and materials or coatings that promote their
use. Chapter 11 introduces A Sensor System for Online Oil Condition Monitoring of Operating
Components with up-to-date web-based accessibility. The electrical oil sensor assists with in‐
creasing the level of machine availability, e.g., of off-shore wind turbines and can also be
used to measure the percentage of biodiesel in a fuel blend.
The editor especially would like to thank the authors for their valuable work. The support of
the publisher is also highly appreciated.
Jürgen Gegner
University of Siegen,
Germany
Section 1
Lubrication and Properties of Lubricants
