Filtern
Erscheinungsjahr
Dokumenttyp
- Beitrag zu einem Sammelband (43) (entfernen)
Sprache
- Englisch (26)
- Deutsch (12)
- Französisch (4)
- Mehrsprachig (1)
Schlagworte
- Friction (4)
- Wear (4)
- DLC (3)
- Tribology (3)
- High toughness steel (2)
- Slip rolling (2)
- Triboaktive Werkstoffe (2)
- (Ti,Mo)(C,N) (1)
- 100C6 (1)
- Al2O3 (1)
Organisationseinheit der BAM
Automotive engine lubricants
(2019)
In 2003, ASTM Manual 37, Fuels and Lubricants Handbook: Technology, Properties, Performance and Testing, featured a chapter discussing automotive lubricants, including engine oils, automatic transmission fluids, manual transmission fluids, gear lubricants, and greases. This chapter, by Schwartz, Tung, and McMillan, surveyed all of these classes of lubricants, up to its publication in 2003.
More recently, the period between 2003 and 2010 has been addressed as part of a book copublished by ASTM and SAE International (coeditors Simon Tung and George Totten), where Fox surveyed the development of engine oil specifications that emerged during those years.
This chapter surveys the evolution of engine oil design and testing since 2002 and concludes with insights into future directions offered by recent tribological research. Our objective is to provide a reader new to the field with an understanding of the following:
- Engine oil composition and formulation
- North American engine oil specification development, and an outline of emergent European specifications
- How emergent specifications and legislative requirements are linked to the introduction of new engine hardware
- How tribological innovation can contribute to future enhancements in engine efficiency
In parallel, we will provide several tables comparing groups of contemporaneous specifications.
The inevitable increase of torque or load, because of lightweight approaches, pushes the oil-film temperatures on the teeth flanks of gears above 200°C, and requires alloys with higher strength and toughness properties. Furthermore, the real temperature on surfaces during the physical vapor deposition (PVD) or chemical vapor deposition (CVD) of thin films can exceed the annealing temperature of the state-of-the-art bearing and gear materials, such as AISI 52100 (1.3505), 16MnCr5 (1.7131), 21NiCrMo (1.6523), and 30CrMoV9 (1.7707). Such trends call for slip-rolling-resistant, alternative alloys suited for contact stresses above P0max of >2.2 GPa. The tribological profile under slip-rolling conditions at 120°C in a factory engine oil (SAE 0W-30, ACEA A3/B4, ν120°C = 5.33 mPa, HTHS150°C = 3.0 mPa) until 10 × 106 load cycles between P0max of 2.25 GPa to 3.92 GPa of uncoated 100Cr6 (1.3505, PBQ), 102Cr6 (1.2067), Cronidur 30 (1.4108, DESU), 45SiCrMo6 (1.8062, CVEM), 40SiNiCrMo1 [vacuum arc remelting (VAR)], CSS-42L (AMS 5932, vacuum induction melting (VIM)-VAR, and carburized), 36NiCrMoV1-5-7 (CAB), ASP2012 (ASP), and 20MnCr5 (1.7131, carburized) was established in twin disk machines (Amsler-type and 2Disk). The present benchmark illuminates the tribological impact of uncoated bearing steels in comparison to uncoated alternative steel alloys on friction, wear and slip-rolling resistance, as well as load carrying capacity. Iron-based steel alloyed with silicon or molybdenum reduces alloying costs and avoids thermo-chemical treatments. This benchmark suggests considering an extension to fracture toughness from hardness and strength as a relevant property for slip-rolling alloys. If slip-rolling resistant, the wear rates of the metallurgical different steels were more or less within one order of magnitude, but the influence of increasing contact stresses on the tribological profile differed significantly.
Wear
(2014)
Original equipment manufacturers (OEMs) and end-users perceive “wear” or “oil drain” differently. Spare parts, Services, and accessories contribute to an important portion to the profit of the OEMs. Maintenance and shutdowns define the operational costs of end-users. Thus, the strategy in order to exploit “wear” depends from the market structure and is up to the reader and/or applicant. The topic “Service Life/Durability/Life Cycle” represents a very ambiguous one and was already thematized in earlier times.
Stribeck curve
(2014)
The importance of lubricants in virtually all fields of the engineering industry is reflected by an increasing scientific research of the basic principles. Energy efficiency and material saving are just two core objectives of the employment of high-tech lubricants. The encyclopedia presents a comprehensive overview of the current state of knowledge in the realm of lubrication. All the aspects of fundamental data, underlying concepts and use cases, as well as theoretical research and last but not least terminology are covered in hundreds of essays and definitions, authored by experts in their respective fields, from industry and academic institutes.
Polyalkyleneglycols are oxygen containing base oils, which enable a) polymer-free formulations with high intrinsic viscosity indices favorable for fuel economy, b) bio-no-tox properties and c) low viscosity formulations with low evaporaions. The oxygen present in each monomer of the backbone of polyalkylene glycols defines intrinsic properties, such as high viscosity indices, low NOACK-evaporation, extreme pressure, high hear capacities, etc., thus enabling metal-, ash- and polymer-free engine oil formulations supporting the functional benefits, such as improved of fuel economy or no adverse effects on after-treatment devices.
Coatings for slip-rolling
(2014)
Biolubrifiants
(2013)
Les huiles perdues, les fuites accidentelles et les lubrifiants perdus rejoignant les sols et les eaux (comme ce fut le cas pour le lac de Constance par exemple) sont l'un des points de departs de la mise en route des lubrifiants « neutres pour l'environnement».
Meme en prenant en compte les voies du recyclage, la combustion dans les moteurs et les fuites connues, environ 30 % (entre 20 % et 40 %, selon les etudes du votume de lubrifiants entrent dans l'environnement par des voies non maitrisees ou sont probablement mis en decharge de maniere illegale. Avec de tels chiffres publies, les arguments des lobbyistes de l'industrie petrochimique, affirmant que, dans la plupart des applications, les fluides sont enfermes dans des reservoirs dos et etanches, ne convainquent pas les politiques. C'est aussi peut-etre parce qu'en Allemagne, environ 60 % des particuliers changent leur huile eux-memes.
Dans une annee d'economie normale, environ 4,5 millions de tonnes de lubrifiants neufs sont vendues dans l'Europe des 15.