Austenitic stainless steel (1.4837Nb) is widely used for turbo housing and other components which are subjected to elevated temperature conditions. Due to assembly constraints, geometry limitation, and particularly high temperatures, thermomechanical fatigue (TMF) issue is commonly seen in the service of the components. Therefore, it is critical to understand the TMF behavior of the steel. In the present study, a series of fatigue tests including isothermal low cycle fatigue (LCF) test at elevated temperatures up to 1000°C, in-phase and out-of-phase TMF tests in different temperature ranges have been conducted. Both creep and oxidation are active in these conditions, and their contributions to the damage of the steel are evaluated. A Chaboche viscoplasticity model for constitutive simulation, and a DTMF damage model for life prediction are developed and validated at specimen level.
Efficient and accurate ordinary differential equation (ODE) solvers are necessary for powertrain and vehicle dynamics modeling. However, current commercial ODE solvers can be prohibitively expensive, leading to a need for accessible, effective, open-source ODE solvers designed for powertrain modeling. Rust is a compiled programming language which has the potential to be used for fast and easy-to-use powertrain models, given its exceptional computational performance, robust package ecosystem, and rapid time for modelers to become proficient. However, of the three commonly used (>3000 downloads) packages in rust with ODE solver capabilities, only one has more than four numerical methods implemented, and none are designed for ease of use in modeling generally physical systems. Therefore, the goal of our research was to implement accurate and efficient ODE solvers in Rust specifically designed for the component-based problems often seen in powertrain modeling.
Baking ovens in the automotive paint shop are crucial to ensuring quality of paint curing and hence meet the corrosion protection targets in manufacturing process. Ovens are also among the most energy consuming processes in the entire paint shop. With the onset of Electric Vehicle revolution, original equipment manufacturers (OEMs) focus heavily on light weighting resulting in significant design changes to the body in white (BIW). This presents a challenge of achieving accurate curing in the existing ovens designed for the current and past generations of vehicles. Using Computational fluid dynamic (CFD), this research intends to present a solution by minimizing the need for prototyping for design changes. Lattice Boltzmann Method (LBM) based thermal simulations are used to predict the curing behaviour on the BIW surface. The LBM based conjugated heat transfer simulations consider turbulence using a Large-Eddy Simulation (LES) approach and Boussinesq approximation.
The test method describes the procedure for determination of the total acid number (TAN) of new and degraded polyol ester and diester-based gas turbine lubricants by the potentiometric titration technique. The method was validated to cover an acidity range of 0.05 to 6.0 mg KOH g-1. The method may also be suitable for the determination of acidities outside of this range and for other classes of lubricants.
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).
Corrosion control is always of concern to the designer of electronic enclosures. The use of EMI gaskets to provide shielding often creates requirements that are in conflict with ideal corrosion control. This SAE Aerospace Recommended Practice (ARP) presents a compatibility table (see Figure 1) which has as its objective a listing of metallic couples that are compatible from a corrosion aspect and which still maintain a low contact impedance.
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).
Magnesium alloys possess a unique combination of benefits stemming from their exceptional strength-to-weight ratio and reduced density. The aforementioned attributes render them notably attractive for utilization in automotive and aeronautical sectors. Furthermore, these alloys are gaining significant interest from the industry because of their outstanding dimensional stability, excellent ability to dampen vibrations, high recyclability, and good castability. They also exhibit superior stiffness, among other attributes. Nonetheless, magnesium and its alloys face several noteworthy challenges that limit their industrial utilization. These include low resistance to deformation over time, limited stability at high temperatures, restricted malleability, poor ductility, and inadequate resistance to corrosion. This study aims to investigate the phenomenon of stress corrosion cracking in magnesium alloy when exposed to potassium chromate. Addition of Ca showed better mechanical properties.
This study focuses on enhancing the corrosion resistance of AZ91D magnesium alloy, known for its impressive strength-to-weight ratio within the magnesium group. Despite its lightweight properties, the alloy's moderate corrosion and wear resistance have restricted its widespread use. To address this limitation, we explored the application of the Dow 17 process to enable hard anodizing of AZ91D magnesium alloy. Our primary objective is to investigate the impact of hard anodizing on AZ91D magnesium alloy and its potential to mitigate corrosion issues. Hard anodizing results in the formation of a robust oxide film on the alloy's surface. We posit that this oxide film can significantly reduce substrate corrosion, expanding the alloy's utility in various applications. To substantiate our claims, we conducted a comprehensive corrosion performance analysis of AZ91D magnesium alloy, with and without hard anodizing treatment.
Wire arc additive manufacturing technology has become a promising alternative technology to high-volume metal deposition in many manufacturing industries like aerospace and automotive due to arc stability, long process cycle time, and formability. In this work, the Fanuc arc mate robot forms a single-pass, single-layer structure with a 1.2 mm diameter wire of copper-coated steel. Pure Argon gas is used as a shielding gas to protect the weld from oxidation. Different welding speed is carried out to analyze the bead thickness and height. Current and voltage as a heat input with optimal welding speed, a 10 kg straight wall is built with an operative building rate of 3.94 kg/h. The Rockwell hardness test is used to determine the hardness of the material, and it is discovered that it is 80 HRB. The tensile test is performed to determine the tensile strength and yield strength of the component; the measured values are 483.88 N/mm2 and 342.156 N/mm2, respectively.
The increased adoption of AA2014 Aluminum alloy within the manufacturing sector can be attributed to its lightweight properties and other attributes that position it as an appealing substitute for steel. Notably, AA2014 Aluminum alloy is employed in the production of components and frameworks for aircraft engines. However, conventional welding techniques do not always seamlessly apply to aluminum alloys due to aluminum's high thermal conductivity, pronounced susceptibility to oxidation, and comparatively low melting point. These characteristics can give rise to challenges such as burn-through and porosity during welding. To tackle these issues, the application of friction stir welding (FSW), a solid-state welding method, has been embraced. In the creation of lap joints, five distinct tools, each featuring a different ratio of tool shoulder diameter (D) to pin diameter (d), ranging from 2 to 4, were employed.
In passenger cars, exterior damage due to external objects is a common and repetitive problem for the costumer. A vehicle running over an unpaved or granular road undergoes such damages where the tyre picks up stones (Figure 1) [1] and ejects them towards the vehicle exterior surfaces. These stones cause mechanical damage to the vehicle: affecting aesthetics, accelerating corrosion, and reducing safety. This mechanical damage is more severe in case of electrical vehicles as batteries are placed at the underside of the vehicle. Figure 2 [2] shows an example damaged caused by stone chipping. Induced erosion due to chipping cause corrosion propagation on the peeled surface, Figure 2 shows an example of such corrosion. So far, physical testing and analytical mathematical methods are the most common ways to evaluate damages. However, there is a need of computationally inexpensive, repeatable, and accurate method, which can account for the complex system.
The automotive sector trend is moving towards vehicle electrification that provides great energy and environmental implications. However, Electrical Vehicles (EVs) are facing challenges in term of charging, driving range and life cycle with respect to existing vehicles. One of the key components in EV which is responsible for charging is On-Board Charger (OBC). OBCs are mainly used in converting DC power from battery pack to AC power and contains different power-electronic devices such as MOSFETs, diodes, magnetics etc. Heat-sinks are used to transfer the heat generated by these electronics and also as an enclosure to accommodate the electronics. Aluminum based alloy-ADC-12 generally used for manufacturing of OBC-enclosure due to its light weight, easy castability and good thermal conductivity. Although ADC-12 aluminum alloy has high corrosion resistance, specific environment condition or situation may accelerate corrosion with extended storage in rainy and salty environments.