Slide Bearing Types for Combustion Engines Designed for Upcoming Emission Regulations

2009 ◽  
Author(s):  
Falko Langbein ◽  
Matthias Loidl ◽  
Alexander Eberhard ◽  
Robert Mergen
Keyword(s):  
High Speed ◽  
Tribological Behavior ◽  
Temperature Stability ◽  
High Strength ◽  
Life Time ◽  
Strength Properties ◽  
Critical Element ◽  
Operating Pressure ◽  
Combustion Engines ◽  
Slide Bearing

Intelligent handling of our limited energy resources and the demand to reduce emissions are today the main drivers for developing efficient combustion engines. Therefore slide bearings and also other parts of the powertrain are facing major challenges caused by: Significantly increased operating pressure, temperature and sliding speed as well as the use of new lubricants and fuels. Furthermore, a ban of hazardous elements (e.g. lead, cadmium) in the applied materials is looming. With respect to above mentioned facts, the mechanical and tribological boundary conditions for bearings in future engines are subjected to change immensely. These changes can only be met by new lining materials and bearing types. From the standpoint of strength, the main critical factors are the soft phases — mainly tin and lead — added to both aluminum and copper based bearing alloys to obtain the necessary tribological behavior. Soft phases are limited in their temperature stability and in addition, lead is an environmental critical element and is restricted. For upcoming engine generations even novel aluminum-tin alloys will reach their performance limits and the classical leaded-bronze material as basis for tri-metal and sputter coatings can no longer cope with the life-time expectations. In addition, corrosion issues will come up due to new oil additives in truck and high speed engines. The present paper proposes, for the application in high speed and truck engines, new slide bearing types with appropriate characteristics and the desired performance required by engine designers: A high strength, thermally stable aluminum alloy with excellent mechanical properties by using re-crystallization inhibition mechanisms; a series of new solutions on the basis of a lead-free bronze linings having brilliant thermo-mechanical process capabilities resulting in high strength properties. Adequate tribological behavior is gained by combination of the new lining alloys with different surface layers. Fundamental working principles, development work and first application results of the new bearing types are presented in relation to existing solutions.

scholarly journals The Effect of Plume Generated on the Microstructural Behavior of the Weld Mixed Zone in High-Speed Laser Dissimilar Welding

Metals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1556
Author(s):  
Su-Jin Lee ◽  
Seiji Katayama ◽  
Jong-Do Kim ◽  
Jeong Suh
Keyword(s):  
Laser Welding ◽  
Fusion Zone ◽  
High Speed ◽  
Welding Process ◽  
High Strength ◽  
Strength Properties ◽  
Material Behavior ◽  
Dissimilar Welding ◽  
Weld Fusion Zone ◽  
Dissimilar Laser Welding

Dissimilar laser welding has been researched to combine the excellent anticorrosion and high strength properties of Ti and the low weight and cost of Al. However, when welding dissimilar Al and Ti sheets, many kinds of intermetallic compound are easily generated. Therefore, intermetallic compounds and differences in material properties make joining such dissimilar metals very difficult. Previous studies clarified that ultra-high welding speed could suppress the weld defects. To elucidate the mechanism of Al and Ti dissimilar laser welding, material behavior of the weld fusion zone and components of fume generated during the ultra-high speed welding process were observed and analyzed using energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), high speed cameras, and a spectrometer. The results show that the atom movement of Al and Ti in the weld plume affects the behavior of elemental components distributed in the weld fusion zone.

A novel predictive method for filler coflocculation with cellulose microfibrils

TAPPI Journal ◽  
2019 ◽  
Vol 18 (11) ◽  
pp. 653-664
Author(s):  
IGNACIO DE SAN PIO ◽  
KLAS G. JOHANSSON ◽  
PAUL KROCHAK
Keyword(s):  
Negative Impact ◽  
High Strength ◽  
Strength Properties ◽  
Cellulose Microfibrils ◽  
Paper Strength ◽  
Flow Loop ◽  
Cationic Starch ◽  
Reflectance Measurement ◽  
Drainage Rate ◽  
Complete Study

Different strategies aimed at reducing the negative impact of fillers on paper strength have been the objective of many studies during the past few decades. Some new strategies have even been patented or commercialized, yet a complete study on the behavior of the filler flocs and their effect on retention, drainage, and formation has not been found in literature. This type of research on fillers is often limited by difficulties in simulating high levels of shear at laboratory scale similar to those at mill scale. To address this challenge, a combination of techniques was used to compare preflocculation (i.e., filler is flocculated before addition to the pulp) with coflocculation strategies (i.e., filler is mixed with a binder and flocculated before addition to the pulp). The effect on filler and fiber flocs size was studied in a pilot flow loop using focal beam reflectance measurement (FBRM) and image analysis. Flocs obtained with cationic polyacrylamide (CPAM) and bentonite were shown to have similar shear resistance with both strategies, whereas cationic starch (CS) was clearly more advantageous when coflocculation strategy was used. The effect of flocculation strategy on drainage rate, STFI formation, ash retention, and standard strength properties was measured. Coflocculation of filler with CPAM plus bentonite or CS showed promising results and produced sheets with high strength but had a negative impact on wire dewatering, opening a door for further optimization.

CYCLOPS BHT

Alloy Digest ◽  
1965 ◽  
Vol 14 (2) ◽  
Keyword(s):  
Fracture Toughness ◽  
Corrosion Resistance ◽  
Elevated Temperature ◽  
High Speed ◽  
High Speed Steel ◽  
High Strength ◽  
Heat Treating ◽  
High Load ◽  
Structural Components ◽  
Temperature Performance

Abstract Cyclops BHT is a low-alloy martensitic high-speed steel of the molybdenum type recommended for high strength, high load structural components designed for elevated temperature service. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: SA-173. Producer or source: Cyclops Corporation.

UNS R54620

Alloy Digest ◽  
1987 ◽  
Vol 36 (7) ◽  
Keyword(s):  
Titanium Alloy ◽  
High Temperature ◽  
Time Use ◽  
Temperature Stability ◽  
High Strength ◽  
Heat Treating ◽  
High Temperature Stability ◽  
Beta Titanium Alloy ◽  
Beta Titanium ◽  
Long Time

Abstract UNS No. R54620 is an alpha-beta titanium alloy. It has an excellent combination of tensile strength, creep strength, toughness and high-temperature stability that makes it suitable for service to 1050 F. It is recommended for use where high strength is required. It has outstanding advantages for long-time use at temperatures to 800 F. This datasheet provides information on composition, physical properties, elasticity, tensile properties, and bend strength as well as creep. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: Ti-86. Producer or source: Titanium alloy mills.

VASCO M-50

Alloy Digest ◽  
1974 ◽  
Vol 23 (11) ◽  
Keyword(s):  
Elevated Temperature ◽  
Physical Properties ◽  
Surface Treatment ◽  
High Speed ◽  
High Speed Steel ◽  
High Strength ◽  
Heat Treating ◽  
High Load ◽  
Aisi 52100 ◽  
Aisi 52100 Steel

Abstract VASCO M-50 is a hardenable (martensitic), low-alloy high-speed steel developed primarily for high-strength, high-load components (such as bearings and gears) designed for elevated-temperature service. It may be used at temperatures up to 600 F; this is in contrast to AISI 52100 steel which may be used up to only 350 F. This datasheet provides information on composition, physical properties, hardness, and elasticity. It also includes information on forming, heat treating, machining, joining, and surface treatment. Filing Code: TS-278. Producer or source: Teledyne Vasco.

Research on High-Speed Cutting of Cr12MoV Hardened Steel - A Review

2020 ◽  
Vol 15 ◽  
Author(s):  
Fei Sun ◽  
Guohe Li ◽  
Qi Zhang ◽  
Meng Liu
Keyword(s):  
High Speed ◽  
Cutting Temperature ◽  
High Hardness ◽  
High Strength ◽  
Hardened Steel ◽  
Parameters Optimization ◽  
Future Research ◽  
High Speed Machining ◽  
Machined Surface ◽  
Stamping Die

: Cr12MoV hardened steel is widely used in the manufacturing of stamping die because of its high strength, high hardness, and good wear resistance. As a kind of mainstream cutting technology, high-speed machining has been applied in the machining of Cr12MoV hardened steel. Based on the review of a large number of literature, the development of high-speed machining of Cr12MoV hardened steel was summarized, including the research status of the saw-tooth chip, cutting force, cutting temperature, tool wear, machined surface quality, and parameters optimization. The problems that exist in the current research were discussed and the directions of future research were pointed out. It can promote the development of high-speed machining of Cr12MoV hardened steel.

Causes of gear pump fails and methods for their elimination

2020 ◽  
pp. 98-107
Author(s):  
Vitaliy A. Zuyevskiy ◽  
Daniil O. Klimyuk ◽  
Ivan A. Shemberev
Keyword(s):  
Adhesion Strength ◽  
Production Systems ◽  
Low Cost ◽  
High Strength ◽  
Strength Properties ◽  
Research Purpose ◽  
Working Fluid ◽  
Gear Pump ◽  
Repair Service ◽  
Recovery Method

Gear pumps are an important element of many production systems and their replacement in case of failure can be quite expensive, so it is important to have a modern and well-tuned technology for their recovery. There are many methods for restoring the pump's performance, depending on the reason that led to its failure. (Research purpose) The research purpose is in determining what causes most often lead to loss of pump performance, and developing a recovery method that provides the greatest post-repair service life of the pump and low cost of repair. (Materials and methods) Authors took into account that the applied coatings must have sufficient adhesion strength and resistance to mechanical, thermal and corrosion loads during operation. It was found that most often significant leaks of the working fluid, leading to failure, occur due to an increase in the gap between the inner surface of the housing and the gears due to active wear of the housing wells. Authors determined that the method of electric spark treatment of worn-out housing wells is best suited to perform the task (a large post-repair resource and low costs). (Results and discussion) It was found by laboratory studies of the adhesion strength of electric spark coatings with various electrodes that the best transfer of the material to the substrate is provided by bronze electrodes BrMKts3-1. It was noted that the coatings applied using the BrMKts3-1 electrode have high strength properties. (Conclusions) Research conducted in the center for collective use "Nano-Center" VIM confirmed the possibility of effective recovery of the gear pump by electric spark treatment.

scholarly journals 2D-3D integration of hexagonal boron nitride and a high-κ dielectric for ultrafast graphene-based electro-absorption modulators

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Hitesh Agarwal ◽  
Bernat Terrés ◽  
Lorenzo Orsini ◽  
Alberto Montanaro ◽  
Vito Sorianello ◽  
...  
Keyword(s):  
Boron Nitride ◽  
Hafnium Oxide ◽  
High Speed ◽  
Hexagonal Boron Nitride ◽  
Temperature Stability ◽  
Cost Effective ◽  
Fold Increase ◽  
Building Blocks ◽  
High Quality ◽  
New Device

AbstractElectro-absorption (EA) waveguide-coupled modulators are essential building blocks for on-chip optical communications. Compared to state-of-the-art silicon (Si) devices, graphene-based EA modulators promise smaller footprints, larger temperature stability, cost-effective integration and high speeds. However, combining high speed and large modulation efficiencies in a single graphene-based device has remained elusive so far. In this work, we overcome this fundamental trade-off by demonstrating the 2D-3D dielectric integration in a high-quality encapsulated graphene device. We integrated hafnium oxide (HfO2) and two-dimensional hexagonal boron nitride (hBN) within the insulating section of a double-layer (DL) graphene EA modulator. This combination of materials allows for a high-quality modulator device with high performances: a ~39 GHz bandwidth (BW) with a three-fold increase in modulation efficiency compared to previously reported high-speed modulators. This 2D-3D dielectric integration paves the way to a plethora of electronic and opto-electronic devices with enhanced performance and stability, while expanding the freedom for new device designs.

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