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Technical Paper

Fault Feature Extraction of Elliptically Shaped Bearing Raceway

2019-06-05
2019-01-1564
The elliptically shaped bearing (ESB) with a rigid, elliptical inner race and a flexible, thin-walled outer race is the most easily damaged core component of harmonic drive. The ESB rotates under cycle load of alternating stress due to its special elliptic structure. Hence, the impact noise produced by alternating between long axis and short axis is apt to conceal the fault features of ESB such as fatigue spalling and pitting. In order to diagnose the fault on raceway surface of ESB, a new method of CMWT-FH based on Continuous Morlet Wavelet Transform (CMWT) and FFT-based Hilbert (FH) spectrum analysis is proposed to extract the fault feature.
Training / Education

Materials Degradation in Mechanical Design Wear, Corrosion, Fatigue and their Interactions

2019-04-09
Materials degradation from environmental conditions is a common factor that will often occur in mechanical equipment used in every type of environment. These processes can frequently materialize in unpredicted and harmful ways, especially when they interact and lead to early component damage or failure. This five-session course will summarize the mechanisms that cause materials and mechanical components to degrade in service through exposure to deleterious mechanical and environmental conditions.
Technical Paper

A Study on Improvement of Optical/Electrical Properties of Indium-Tin-Oxide Thin Films Prepared by Sol-Gel Process

2019-04-02
2019-01-0187
Ar plasma treatment was carried out to reduce the sheet resistance of indium tin oxide (ITO) thin films. To verify how the concentration of oxygen vacancies in the film increased with the Ar plasma treatment time, cumulative and continuous plasma treatments were conducted. In addition, to improve the transmittance and reduced the sheet resistance the PDMS layer was as a stamp on the surface of ITO. The oxidation of the PDMS stamp appears to be a key factor to improve the characteristics of ITO thin film. Furthermore, an indium-tin-oxide (ITO) thin film with approximately 50 nm thickness was successfully synthesized on glass substrates by using a fully aqueous sol-gel process. The annealing temperature and argon plasma treatment time appear to be key factors in reducing resistivity and increasing the transmittance of the thin film.
Technical Paper

Consideration of Corrosion Behavior of Aluminum Wire at Crimped Terminal and Effective Anti-Corrosion Treatment

2019-04-02
2019-01-0486
The demand for weight reduction of vehicles is growing in compliance with CO2 emission control requirements. Also, demand for copper is on the rise with an increase in the number of electric vehicles because their motors and wiring require a lot of copper. This has raised concerns about higher copper prices and vehicle weight. Recently, attempts to reduce vehicle weight have been actively made by partially replacing copper with aluminum, which is lighter and less expensive. Although the use of aluminum wires on limited areas of some vehicles has already been reported, that on all areas has not been reported yet. The authors focus on reducing weight of wiring harnesses, which is about 20 kg per vehicle, and consider using aluminum instead of copper as the conductor of the electrical wires. One of the factors impeding the use of aluminum wires in wider areas is galvanic corrosion occurring at crimped terminals.
Technical Paper

Screening of Potential Biomass-Derived Streams as Fuel Blendstocks for Mixing Controlled Compression Ignition Combustion

2019-04-02
2019-01-0570
Mixing controlled compression ignition, i.e., diesel engines are efficient and are likely to continue to be the primary means for movement of goods for many years. Low-net-carbon biofuels have the potential to significantly reduce the carbon footprint of diesel combustion and could have advantageous properties for combustion, such as high cetane number and reduced engine-out particle and NOx emissions. We developed a list of over 400 potential biomass-derived diesel blendstocks and populated a database with the properties and characteristics of these materials. Fuel properties were determined by measurement, model prediction, or literature review. Screening criteria were developed to determine if a blendstock met the basic requirements for handling in the diesel distribution system and use as a blend with conventional diesel. Criteria included cetane number ≥40, flashpoint ≥52°C, and boiling point or T90 ≤338°C.
Technical Paper

Topology Optimization of Metal and Carbon Fiber Reinforced Plastic (CFRP) Structures under Loading Uncertainties

2019-04-02
2019-01-0709
Carbon fiber reinforced plastic (CFRP) composite materials have gained particular interests due to their high specific modulus, high strength, lightweight and perfect corrosion resistance. However, in reality, CFRP composite materials cannot be used alone in some critical places such as positions of joints with hinges, locks. Therefore, metal reinforcements are usually necessary in local positions to prevent structure damage. Besides, if uncertainties present, obtained optimal structures may experience in failures as the optimization usually pushes solutions to the boundaries of constraints and has no room for tolerance and uncertainties, so robust optimization should be considered to accommodate the uncertainties in practice. This paper proposes a mixed topology method to optimize metal and carbon fiber reinforced plastic composite materials simultaneously under nondeterministic load with random magnitude and direction.
Technical Paper

A Test Rig for Evaluating Thermal Cyclic Life and Effectiveness of Thermal Barrier Coatings inside Exhaust Manifolds

2019-04-02
2019-01-0929
Thermal Barrier Coatings (TBCs) may be used on the inner surfaces of exhaust manifolds in heavy-duty diesel engines to improve the fuel efficiency and prolong the life of the component. The coatings need to have a long thermal cyclic life and also be able to reduce the temperature in the substrate material. A lower temperature of the substrate material reduces the oxidation rate and has a positive influence on the thermo-mechanical fatigue life. A test rig for evaluating these properties for several different coatings simultaneously in the correct environment was developed and tested for two different TBCs and one oxidation-resistant coating. Exhausts were redirected from a diesel engine and led through a series of coated pipes. These pipes were thermally cycled by alternating the temperature of the exhausts. Initial damage in the form of cracks within the top coats of the TBCs was found after cycling 150 times between 50°C and 530°C.
Training / Education

Fuel Systems Material Selection and Compatibility with Alternative Fuels

2019-04-02
This course will introduce the participants to the factors governing fuel-material compatibility and methods to predict and empirically determine compatibility for new alternative fuel chemistries.  By understanding the mechanisms and factors associated with chemically-induced degradation, participants will be able to assess the impact of fuel chemistry to infrastructure components, including those associated with vehicle fuel systems.  This course is unique in that it looks at compatibility from a fuel chemistry perspective, especially new fuel types such as alcohols and other biofuels. 
Technical Paper

Impact of TiO2 and V2O5 on Sintered Mullite Porous Microstructure and Soot Oxidation Kinetics Using SEM and TGA

2019-03-25
2019-01-1407
The exhaust emissions from diesel combustion are the sources of particulate matter emitted to the atmosphere, which are components of air pollution that implicated in human health such as lung cancer. At present the diesel particulate filter can remove PM from the exhaust gas before emitted to the atmosphere. This research is investigating morphology and structure of acicular mullite to develop the fabrication process filter in order to study particulate matters trapping and oxidation mechanisms. This paper used two main substances to study the structure of diesel particulate filter (DPFs); Aluminum oxide (Al2O3) and Silicon dioxide (SiO2). These are mainly in the conventional DPFs. The variable substances are Titanium dioxide (TiO2) and Vanadium oxide (V2O5), which added to investigate and produce the acicular mullite DPFs structure. The mullite samples were sintered at 1300 oC with holding time of 1 h.
Standard

Electroless Nickel-Boron Plating

2019-03-18
CURRENT
AMS2399C
This specification covers the engineering requirements for electroless deposition of nickel-boron on various materials and the properties of the deposit.
Standard

Insulating Compound, Electrical, Embedding, Reversion Resistant Silicone

2019-03-06
WIP
AS81550B
This specification covers the requirements for two types of a two-part, transparent, reversion resistant flexible insulating compound, to provide resilient, environmental, and electrical insulation of components in systems in temperature range 85 to 392 °F (-65 to 200 °C). These insulating compounds are intended for embedding, potting or encapsulation of electrical and electronic components in systems where tear resistance is not critical but their use is not limited to such applications. These transparent compounds allow visual circuit and part identification and facilitates part replacement and repairs. The insulating compound shall cure in sections of unlimited thickness, either exposed to air or completely sealed.
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