Thermo-mechanical fatigue and natural aging due to environmental conditions are difficult to simulate in an actual test with the advanced fiber-reinforced composites, where their fatigue and aging behavior is little understood. Predictive modeling of these processes is challenging. Thermal cyclic tests take a prohibitively long time, although the strain rate effect can be scaled well for accelerating the mechanical stress cycles. Glass fabric composites have important applications in aircraft and spacecraft structures including microwave transparent structures, impact-resistant parts of wing, fuselage deck and many other load bearing structures. Often additional additively manufactured features and coating on glass fabric composites are employed for thermal and anti-corrosion insulations. In this paper we employ a thermo-mechanical fatigue model based accelerated fatigue test and life prediction under hot to cold cycles.
The traditional aircraft towing system primarily relies on the traction vehicle’s power to accomplish braking. However, In the new type of high-speed aircraft towing system, relying solely on the traction vehicle for braking leads to issues such as excessive braking distance and high impact forces on the landing gear, which may increase accident risks. In order to enhance the braking performance of the towbarless aircraft taxiing system(TLATS) and ensure the safety of the landing gear, a new model of joint braking by the aircraft and the towbarless towing vehicle(TLTV) is established.
Rotary Bell Atomizers are well established in the automotive industry for top coating applications. This type of atomizers allows to create a uniform coating and are characterized by high productivity. Meanwhile, the effectiveness of the process depends on many complex factors. For instance, the transfer efficiency of the paint material, which is the percentage of the paint reaching the structure surface, ranges from 60-90% depending on the application conditions. Any increase in the transfer efficiency can not only reduce energy and material costs, but also reduce the emission of harmful non-deposited paint particles and the effort to handle them. The use of accurate numerical methods in this process helps to optimize the application process, reduce the number of expensive field experiments, and shortens the development cycle of new vehicles, which ensures predictability of production costs.
FMVSS No. 205, “Glazing Materials,” uses impact test methods specified in ANSI/SAE Z26.1-1996. NHTSA’s Vehicle Research and Test Center initiated research to evaluate a subset of test methods from ANSI Z26.1-1996 including the 227 gram ball, shot bag, and dart impact tests, and the fracture test. Additional research was completed to learn about potential changes to tempered glass strength due to the ceramic paint area (CPA), and to compare the performance of twelve by twelve inch flat sample and full-size production parts. Glass evaluated included tempered rear quarter, sunroof and backlight glazing and laminated windshield glazing. Samples with a paint edge were compared to samples without paint, and to production parts with and without paint in equivalent impact tests. A modified shot bag with stiffened sidewalls was compared to the ANSI standard shot bag. The fracture test comparison included evaluating the ANSI Z26.1 punch location and ECE R43 punch location.
This SAE Standard covers motor vehicle brake fluids of the nonpetroleum type, based upon glycols, glycol ethers, and appropriate inhibitors, for use in the braking system of any motor vehicle such as a passenger car, truck, bus, or trailer. These fluids are not intended for use under arctic conditions. These fluids are designed for use in braking systems fitted with rubber cups and seals made from styrene-butadiene rubber (SBR), or a terpolymer of ethylene, propylene, and a diene (EPDM).
This SAE Standard covers motor vehicle brake fluids of the nonpetroleum type, based upon glycols, glycol ethers, and borates of glycol ethers, and appropriate inhibitors for use in the braking system of any motor vehicle, such as a passenger car, truck, bus, or trailer. These fluids are not intended for use under arctic conditions. These fluids are designed for use in braking systems fitted with rubber cups and seals made from styrene-butadiene rubber (SBR) or a terpolymer of ethylene, propylene, and a diene (EPDM).
This SAE Information Report is intended to provide a guide to mechanical and machinability characteristics of some SAE steel grades. The ratings and properties shown are provided as general information and not as requirements for specifications unless each instance is approved by the source of supply. The data are based on resources which may no longer be totally accurate. However, this report is retained as a service in lieu of current data.
This SAE Recommended Practice provides an orderly series for designating the thickness of unocated and coated hot-rolled and cold-rolled sheet and strip. This document also provides methods for specifying thickness tolerances.
The limitations of commonly used materials such as steel in withstanding high temperatures led to exploring alternative alloys. For instance, Inconel 825 is a nickel-based alloy known for its exceptional corrosion resistance. Thus, the Inconel 825 is used in various applications, including aerospace, marine propulsion, and missiles. Though it has many advantages, machining this alloy at high temperatures could be challenging due to its inadequate heat conductivity, increased strain hardening propensity, and extreme dynamic shear strength. The resultant hardened chips generated during high-speed machining exhibit elevated temperatures, leading to tool wear and surface damage, extending into the subsurface. This work investigated the influence of varying process settings on the machinability of Inconel 825 metal, using both uncoated and coated tools.
Using dc magnetron sputtering, Al/Si films were made on surfaces made of fused quartz and silicon. It was carefully controlled that the films contained no more than 7 at.% silicon under ideal deposition conditions. This was done by changing the target's structure and adding silicon lines to it. This had to be done to get a good reading on how much silicon was in the plates. After being heated to 800°C and then cooled in very cold water, the thermo-elastic face-centered cubic structure changed into the flat crush test martensite. In Al/Si films with a Si content of 25.6%, this change took place. It looks like the shift in the opposite way was also thermoelastic. The several thermoelastic transitions that happened were caused by changes in temperature. Some Al-36 at.% Si coatings that were scraped off of a quartz substrate showed shape memory qualities when heated after being deformed. The coverings on these things were warped.
Magnesium and its alloys are promising engineering materials with broad potential applications in the automotive, aerospace, and biomedical fields. These materials are prized for their lightweight properties, impressive specific strength, and biocompatibility. However, their practical use is often hindered by their low wear and corrosion resistance. Despite their excellent mechanical properties, the high strength-to-weight ratio of magnesium alloys necessitates surface protection for many applications. In this particular study, we employed the plasma spraying technique to enhance the low corrosion resistance of the AZ91D magnesium alloy. We conducted a wear analysis on nine coated samples, each with a thickness of 6mm, to assess their tribological performance. To evaluate the surface morphology and microstructure of the dual-phase treated samples, we employed scanning electron microscopy (SEM) and X-ray diffraction (XRD).
The ferrous deuteroporphyrin cast Fe alloy and nickel-coated steel were lap welded successfully using the mechanical stir welding process. It was able to weld junctions with full strength and fracture on the base metal side of nickel-coated steel during the welding process, but ferrous alloy and nickel steel could not be welded together. It was proposed that the joining technique and function of the Ni coating be used in the friction stir lap welding of Ni-coated steel and aluminum alloy. The Ni coating improved both the weldability of iron and steel, resulting in the production of a Fe-Ni eutectic structure with a low melting point at the interface of the two materials. It is possible to successfully fuse steel and ferrous metals together.
Metal matrix composite processing allows the possibility of improving both mechanical and damping properties by selecting reinforcements which have high damping characteristics, hardness and strength. In this work, the effect of disperse SiC as passive agents on the dynamic properties such as damping ratio, loss factor and effect of damping factor on Al7075/Al2O3/SiC composite machinability was studied. The composite samples were fabricated as Al7075/5%Al2O3, Al7075/5%Al2O3/5%SiC, Al7075/5%Al2O3/10%SiC and Al7075/5%Al2O3/15%SiC as well subsequently experimented. The dynamic properties were found using free vibration test approach and the hysteresis loop method. Further, the machinability in end milling operation was accessed by experimentation with the surface finish as the parameter under scrutiny. The composite Al7075/5%Al2O3/5%SiC has better damping ratio comparing to others, also the composite with the best damping capacity produces a fine surface finish during machining.