Browse Topic: Materials properties

Items (31,791)
Find
Methodology for Fast-Running, Time-Resolved Simulation of Non-Exhaust Particle Emissions from Brake Wear Abrasion2025-01-0275To be published on 07/02/2025
Non-exhaust particle emissions, particularly those generated by brake wear, are a significant source of fine particulate matter in urban environments. These emissions contribute to air pollution and pose serious health risks, particularly in densely populated areas. While vehicle exhaust emissions have been extensively studied and regulated, the contribution of non-exhaust sources, including brake wear, remains a critical factor in air quality management. This paper presents a novel methodology for fast-running, time-resolved simulation of non-exhaust particle emissions, specifically those from brake wear abrasion. A 3D CFD model computes the turbulent flow field around the disc brake. The resulting information on the convective air cooling is applied as boundary conditions on a 3D thermal model. This thermal simulation setup is compared and verified with experimental data from literature. The 3D numerical models produce data and boundary conditions for an efficient 1D numerical
Herkenrath, Ferris, Lückerath, Moritz, Günther, Marco, Pischinger, Stefan
Technical Paper
Improving Gearbox Acoustics Through Elastomer-Based Bearing Damping2025-01-0323To be published on 07/02/2025
This study analyses the effect of external damping of roller bearings on the acoustic behaviour of gearboxes in electric powertrains. The increasing adoption of electric vehicles has increased the importance of mitigating gearbox noise, as the lack of masking noise from internal combustion engines and the higher operating speeds of electric motors exacerbate the acoustic challenges. Gearbox noise, which is primarily caused by tooth mesh excitation and its transmission through shafts and bearings, requires strategies to minimise its impact on vehicle comfort and performance. External damping is introduced via adapters integrated into the outer bearing ring, which are used to modify the vibrational behaviour of the bearing assembly and reduce both structure-borne and airborne noise emissions. A systematic approach using Design of Experiments (DoE) methodology is used to quantify the effects of this damping. This approach allows the analysis of critical parameters including material
von Schulz, Kai, Linde, Tilmann, Jäger, Steffen
Technical Paper
Evaluation of Static and Dynamic stiffness of rubber grommet by experimental and FEA method2025-01-0274To be published on 07/02/2025
Vibration control is most important in automotive applications and generally rubbers are used to dampen these vibrations due to their inherent nature and low-cost manufacturing methods. Now to select a rubber material shore hardness is considered in engineering applications, but to additionally control the behaviour we need to understand its static and dynamic stiffness. These values help to determine the vibration isolation obtained by these rubbers. In this paper, we will discuss methods to calculate the static and dynamic stiffness of rubber grommets using experimental methods and FEA modelling. As elastomers have non-linear material properties various material modelling techniques in FEA are used to capture multiple phenomena like creep, fatigue and dynamic conditions. Rubber compounding is used to improve the physical and chemical properties which in turn would give desirable linear characteristics. Certain guidelines and thumb rules are used in the rubber industry for different
Khamkar, Prasad Subhash, Gaikwad, Vikrant C
Technical Paper
Modern Low Friction Coating Technology for Automotive Tribology2025-01-0247To be published on 06/16/2025
According to Forbes, China, armed with electric vehicles (EVs), could have several companies among the top 10 global brands by sales in 2030. Their global market share is expected to be 33% in 2030. EV's friction is mostly boundary and mixed lubrication, more severe than ICE with hydrodynamic lubrication. Electrical surface failures are clustering, frosting, fluting, cratering, white etching, color change of grease, current marks, gear fluting and microbubbles. Modified friction test condition of ball on disk for EV parts is 1 m/s, 50 N, 1.1 GPa, 80 V, 12.5 kHz (vs. conventional pin on disk, 0.1 m/s, 10 N, 1 km). For the protection of EV's wear and friction, the coatings, DLC, CrN and CrCuN, are compared in the literature. Global coating companies developed with the keywords: hybrid process (PVD/PACVD + FLAD), low-temperature process for polymer/seal coating (ta-C), HIPIMS+CVD for CFRP cutting tool. Fraunhofer IWS has a low friction coating project for ultra-smooth and super
Cha, Sung Chul, Moon, Kyoung Il, Kim, Jongkuk, Park, Chang Ho, Kim, Dong Sik
Technical Paper
Influence of Fuel Surface Tension and Viscosity on Internal Flow Bubble Formation and Atomization in Flash Boiling Sprays2025-01-0221To be published on 06/16/2025
Flash boiling spray can achieve atomization effects similar to high-pressure subcooled sprays at lower injection pressures, which reduces engine hardware costs and aligns with the trend toward increased efficiency and miniaturization for hybrid vehicle engines. Thus, it is considered a promising next-generation fuel atomization technology. The atomization characteristics and spray structure of flash boiling sprays differ significantly from those of subcooled sprays, with distinct mechanisms in the primary breakup stage being a major cause of these differences. Previous studies have established the bubble-rupture primary breakup model, which is closely linked to bubble generation during internal flow. However, existing research has primarily focused on controlling the superheat index and injection pressure, without sufficiently considering the impact of fuel properties on bubble generation. As carbon neutrality goals advance, alternative fuels such as e-fuels (e.g., e-gasoline), low
Zhang, Yijia, Li, Yilong, Wang, Shangning, Zeng, Tingxi, Xu, Min, Hung, David, Li, Xuesong
Technical Paper
Data-Driven Machine Learning Approach for Rattle Risk Mitigation2025-01-0126To be published on 05/05/2025
In the modern automotive industry, squeak and rattle issues are critical factors affecting vehicle perceived quality and customer satisfaction. Traditional approaches to predicting and mitigating these problems heavily rely on physical testing and simulation technologies, which can be time-consuming and resource-intensive, especially for larger models. In this study, we propose a data-driven machine learning approach to mitigate rattle risks more efficiently. In this study, a floor console model has been evaluated using the traditional simulation-based E-line method to pinpoint high-risk areas. Data generation is performed by varying material properties, thickness, and flexible connection stiffness using the Modified Extensible Lattice Sequence (MELS) sampling algorithm, creating a diverse and comprehensive dataset for generating a machine learning (ML) model. Utilizing the dataset, the top contributing variables were identified for training the ML models. Various machine-learning
Parmar, Azan, Rao, Sohan, Reddy, Hari Krishna
Technical Paper
Snap-fits evaluation for minimizing the Squeak & Rattle in Automotives2025-01-0091To be published on 05/05/2025
The world of plastic products has been growing due to its versatile properties, which have become an intrinsic and fundamental part of the engineering of new products. The most important aspects contributing to this spectacular growth are the design and assembly, making sure that plastic parts are designed optimally. The safety requirements have been increased due to the safety ratings and thus interior parts must provide more absorption and protection to occupants. The main connection types used in the plastic parts are heat stakes and snap fits. The purpose of a good snap fit is not only to have a high retention effort but also to present ergonomic characteristics with low insertion and extraction effort because each part requires a different function. With the time-dependent loading the material will redistribute its internal energy thereby performing a time-related flow leading to reduced pretension thus decreasing stiffness. This paper presents an analytical and numerical method
Michael Stephan, Navin Estac Raja, C M, Mithun, Mohammed, Riyazuddin, R, Prasath
Technical Paper
Evaluating Powertrain Mount Decoupling: Insights from Simulation, Experimental Results, and Analytical Calculations2025-01-0022To be published on 05/05/2025
This study presents a thorough examination of engine mount decoupling by integrating virtual simulations, physical testing, and analytical calculations. Engine mounts are crucial for isolating vibrations and enhancing vehicle comfort and performance, making their dynamic behavior vital for effective design. In our approach, we employ multi-body dynamics (MBD) simulations to model the interactions within engine mounts. By adjusting the bush stiffness parameters in the MBD framework, we can predict decoupling frequencies and analyze kinetic energy distribution. The bush stiffness values used in simulations are then applied in physical testing, ensuring consistency in the results for decoupling frequencies and kinetic energy distribution. This alignment between virtual and empirical data significantly enhances the reliability of our findings. Moreover, we conduct analytical calculations that correspond with the results from both the simulations and physical tests. This comprehensive
Shende, Kalyani, Shingavi, Shreyas, Rane, Vishesh, Hingade, Nikhil
Technical Paper
Material Adapted Method for the Repair of Curved Thermoplastic Composite Structures by Induction Welding of Patches2025-01-0165To be published on 05/02/2025
Thermoplastic fiber-reinforced polymer composites (TPCs) are gaining importance in aviation due to their high strength, stiffness, and recyclability. To maximize their potential, efficient repair methods are needed to maintain aircraft safety and structural integrity. This article introduces a novel repair technique for damaged TPC structures, involving the insertion of a repair patch with a susceptor material. The susceptor consists of a material with high electrical conductivity and magnetic permeability and therefore reacts stronger to the electromagnetic field than the composite, even if it is carbon fiber based. This means that the thermal energy is specifically concentrated in the repair area. The susceptor can be placed on the patch surface or in the welding zone. The process begins by identifying and preparing the damaged area, followed by precise scarfing. Care is taken to ensure that the surrounding material remains intact and that an exact stepped structure is created, which
Geiger, Markus, Glaap, Anton, Schiebel, Patrick, May, David
Technical Paper
Conceptual Design of a Superconducting Aero Electric Engine System2025-01-0146To be published on 05/02/2025
The goal of the development of an electric aircraft engine is to create an aircraft system that achieves ultimate efficiency using hydrogen fuel instead of fossil fuels. Therefore, it is necessary to focus on reducing weight as much as possible, and this paper describes the approach to such fuel cell-powered aircraft. The authors have adopted a superconducting coreless rotating electric machine with an integrated hydrogen tank and are pursuing a target of 70kg or less for the main components of a 2MW rotating electric machine. High-temperature superconducting wires have zero electrical resistance and can carry a very high current density, but the alternating current (AC) loss generated when used in AC has been an issue in their application to rotating electric machines. In 2023, The SCSC cable was developed to be a low-AC-loss, robust, and high current cable concept, in which copper-plated multifilament coated conductors are wound spirally on a core. In addition to using this
Oyori, Hitoshi, Sakurai, Sho, Kusase, Shin, Yoshida, Yukihiro, Yoshinaga, Seiichiro, Nose, Hiroyuki, Amemiya, Naoyuki
Technical Paper
Advancements in Lightning Strike Damage Modeling: Finite Element Model to Predict Thermal Damage Induced on Composites01-18-02-000704/21/2025
Modern aircraft, ships, and offshore structures are increasingly constructed using fiber-reinforced composite materials. However, when subjected to lightning strikes, these materials can suffer significant structural and functional damage due to their electrical and thermal properties. This study aims to develop a novel finite element (FE) model to minimize the error in estimating the thermal damage caused during lightning strikes. This will aid in design and optimization of lightning protection systems. The developed model introduces a simplified numerical approach to model the lightning arc interaction with CFRP laminate. The existing FE model includes idealized loading conditions, leading to high error in estimation of severe damage area and in-depth damage. The proposed methodology incorporates a more realistic lightning-induced loading pattern to improve accuracy. Several cases are analyzed using available FE methods and compared to the proposed model (case 6) to evaluate the
Sontakkey, Akshay, Kotambkar, Mangesh, Kaware, Kiran
Journal Article
Development of NOx Storage Catalyst and Investigation of Deterioration Mechanism for Small Powertrains2024-32-009704/18/2025
In response to the evolving landscape of exhaust gas regulations for small powertrains, reducing NOx emission is increasingly important. This study deeply investigated the feasibility of a NOx storage catalyst (NSC) containing cerium oxide (CeO2) and barium oxide (BaO) for reducing NOx emission. The key functions, NOx storage and reduction performances were evaluated, and deterioration mechanisms were explored through performance evaluations and physical property analyses. The findings revealed a strong correlation between the size of CeO2 crystals and NOx storage performance at low temperature, such as those encountered during city driving conditions. Conversely, at high temperature, such as those during highway driving conditions, NOx storage performance correlated well with sulfur deposition, suggesting that the formation of barium sulfate (BaSO4) contributes to the deactivation. This experiment also showed a strong correlation between NOx reduction performance and BaSO4 formation
Nakano, Fumiya, Koito, Yusuke
Technical Paper
Fatigue Analysis of Motorcycle Rear Swing Arm on Different Road Surfaces2024-32-004604/18/2025
The rear swing arm, a crucial motorcycle component, connects the frame and wheel, absorbing the vehicle’s load and various road impacts. Over time, these forces can damage the swing arm, highlighting the need for robust design to ensure safety. Identifying potential vulnerabilities through simulation reduces the risk of failure during the design phase. This study performs a detailed fatigue analysis of the swing arm across different road conditions. Data for this research were collected from real-vehicle experiments and simulation analyses, ensuring accuracy by comparing against actual performance. Following CNS 15819-5 standards, road surfaces such as poorly maintained, bumpy, and uneven roads were tested. Using Motion View, a comprehensive multi-body dynamic model was created for thorough fatigue analysis. The results identified the most stress-prone areas on the swing arm, with maximum stress recorded at 109.6N on poorly maintained roads, 218.3N on bumpy surfaces, and 104.8N on
Chiou, Yi-Hau, Hwang, Hsiu-Ying, Huang, Liang-Yu
Technical Paper
Investigation on the Wear Regime of Plastic Gears Sliding Against Metal Gears2024-32-009904/18/2025
The use of plastic gears has expanded due to their lightweight properties, low noise emission, and cost-effective manufacturing. For instance, in the transportation equipment industry, some metal gears are being replaced with plastic gears. To achieve further size and weight reduction, gears must be able to withstand higher loads without damage. Gears have various modes of damage. Since there are different types of wear, each with different factors, it is important to identify the factors and take appropriate countermeasures. In gear meshing, there are many factors that affect wear, so restricted-factor tests are required to confirm the effectiveness of countermeasures. The purpose of this study is to elucidate the wear regime in high-load gear meshing and then to establish a simplified evaluation method replicating the meshing of gears for wear resistance focusing on the relative sliding between the two surfaces of metal and plastic. In the evaluation, changes in wear morphology over
Yamamoto, Jimpei, Suzuki, Takaharu, Ako, Natsuki, Iwasaki, Shinya, Kurita, Hirotaka
Technical Paper
Hose Assembly, Convoluted Polytetrafluoroethylene, Metallic Reinforced, Low Pressure, Up to 400 °F, AircraftAS1227C (Current)04/14/2025
This SAE Aerospace Standard (AS) defines the requirements for a convoluted polytetrafluoroethylene (PTFE) lined, metallic reinforced, hose assembly suitable for use in aerospace fluid systems at temperatures between -65 °F and 400 °F for Class 1 assembly, -65 °F and 275 °F for Class 2 assembly, and at operating pressures per Table 1. The use of these hose assemblies in pneumatic storage systems is not recommended. In addition, installations in which the limits specified herein are exceeded, or in which the application is not covered specifically by this standard, shall be subject to the approval of the procuring activity.
G-3, Aerospace Couplings, Fittings, Hose, Tubing Assemblies
Technical Standard
Cobalt Alloy, Corrosion- and Heat-Resistant, Round Wire 20Cr - 15Ni - 40Co - 7.0Mo - 16Fe (Elgiloy®) Vacuum Induction Melted, Vacuum Consumable Electrode or Electroslag Remelted, Solution Heat Treated and Cold DrawnAMS5833F (Current)04/14/2025
This specification covers a corrosion- and heat-resistant cobalt alloy in the form of round wire 0.001 to 0.140 inch (0.025 to 3.56 mm), inclusive, in nominal diameter supplied in straight lengths or coils.
AMS F Corrosion and Heat Resistant Alloys Committee
Material Specification
Cobalt Alloy, Corrosion and Heat Resistant, Round Wire 20Cr - 15Ni - 40Co - 7.0Mo - 16Fe (Elgiloy®) Vacuum Induction Melted Plus Vacuum Consumable Electrode or Electroslag Remelted, Solution Heat Treated, Cold Drawn, and AgedAMS5834F (Current)04/14/2025
This specification covers a corrosion- and heat-resistant cobalt alloy in the form of round wire 0.001 to 0.140 inch (0.025 to 3.56 mm), inclusive, in nominal diameter supplied in straight lengths or coils (see 8.7).
AMS F Corrosion and Heat Resistant Alloys Committee
Material Specification
Aluminum Alloy Extrusions, 7.8Zn - 2.6Mg - 2.0Cu - 0.10Zr - (7068-T6511), Solution Heat Treated, Stress Relieved, and Precipitation Heat TreatedAMS4331B (Current)04/14/2025
This specification covers an aluminum alloy in the form of extruded bars, rods, shapes (profiles), and tubing 0.250 to 3.000 inches (6.35 to 76.20 mm), inclusive, in nominal diameter, least thickness, or nominal wall thickness (see 8.5).
AMS D Nonferrous Alloys Committee
Material Specification
Titanium Alloy, Sheet, Strip, and Plate, 5Al - 2.5Sn, Extra Low Interstitial, AnnealedAMS4909M (Current)04/14/2025
This specification covers a titanium alloy in the form of sheet, strip, and plate up to 1.000 inch (25.40 mm), inclusive (see 8.6).
AMS G Titanium and Refractory Metals Committee
Material Specification
Aluminum Alloy, Extrusions, 1.0Mg - 0.60Si - 0.28Cu - 0.20Cr (6061-T4), Solution Heat Treated and Naturally AgedAMS4161K (Current)04/14/2025
This specification covers an aluminum alloy in the form of extruded bars, rods, wire, shapes, profiles, and tubing.
AMS D Nonferrous Alloys Committee
Material Specification
Trace Element Control Nickel Alloy Castings and PowderAMS2280E (Current)04/14/2025
This specification establishes testing methods and maximum permissible limits for trace elements in nickel alloy castings and powder materials. It shall apply only when required by the material specification.
AMS F Corrosion and Heat Resistant Alloys Committee
Material Specification
Steel, Corrosion-Resistant, Bars, Forgings and Forging Stock, 11.5Cr - 10Ni - 1.0Al - 0.5Ti - 1.0Cu - 1.0W (S240®), Premium Aircraft Quality Vacuum Induction Plus Vacuum Consumable Electrode Melted Solution Heat Treated, Precipitation HardenableAMS5929B (Current)04/14/2025
This specification covers a corrosion-resistant steel in the form of bars and forgings 8 inches (203 mm) and under in nominal diameter or maximum cross-sectional dimension and forging stock of any size.
AMS F Corrosion and Heat Resistant Alloys Committee
Material Specification
Gaseous NitrocarburizingAMS2759/13A (Current)04/14/2025
This specification covers the engineering requirements for producing a continuous compound zone (white layer) on parts by means of a gaseous, low-temperature, carbon-enriched nitriding process.
AMS B Finishes Processes and Fluids Committee
Material Specification
Magnesium Alloy Castings, Permanent Mold, 10Al (AM100A-T6), Solution and Precipitation Heat TreatedAMS4483F (Current)04/14/2025
This specification covers a magnesium alloy in the form of permanent mold castings (see 8.6).
AMS D Nonferrous Alloys Committee
Material Specification
Aluminum Alloy, Seamless Drawn Tubing, 1.0Mg - 0.60Si - 0.28Cu - 0.20Cr (6061-T4), Solution Heat Treated and Naturally AgedAMS4480B (Current)04/14/2025
This specification covers an aluminum alloy in the form of seamless drawn tubing from 0.025 to 0.500 inch (0.64 to 12.70 mm), inclusive, in wall thickness (see 8.5).
AMS D Nonferrous Alloys Committee
Material Specification
Fluid, Aircraft Deicing/Anti-Icing, SAE Type IAMS1424T (Current)04/14/2025
This foundation specification (AMS1424T) and its associated category specifications (AMS1424/1 and AMS1424/2) cover a deicing/anti-icing material in the form of a fluid.
G-12ADF Aircraft Deicing Fluids
Material Specification
Aluminum Alloy, Die and Hand Forgings and Rolled Rings, 5.6Zn - 2.5Mg - 1.6Cu - 0.23Cr (7075-T6), Solution and Precipitation Heat TreatedAMS4126E (Current)04/14/2025
This specification covers an aluminum alloy in the form of die forgings 4 inches (102 mm) and under in nominal thickness at time of heat treatment, hand forgings up to 6 inches (152 mm), inclusive, in as-forged thickness, rolled rings with wall thickness up to 3.5 inches (89 mm), inclusive, and stock of any size for forging or rolled rings (see 8.6).
AMS D Nonferrous Alloys Committee
Material Specification
Aluminum Alloy, Hand Forgings, 5.6Zn - 2.5Mg - 1.6Cu - 0.23Cr (7075-T7452), Solution Heat Treated, Stress Relieved, and Precipitation Heat TreatedAMS4323E (Current)04/14/2025
This specification covers an aluminum alloy in the form of hand forgings up to 6 inches (152 mm), inclusive, in nominal as-forged thickness and having a cross-sectional area of not more than 156 square inches (1006 cm2) (see 8.7).
AMS D Nonferrous Alloys Committee
Material Specification
Titanium Alloy, Sheet and Strip, 15Mo - 3.0AI - 2.8Cb - 0.20SiAMS4897F (Current)04/14/2025
This specification covers a titanium alloy in the form of sheet and strip 0.125 inch (3.18 mm) and under in nominal thickness (see 8.6).
AMS G Titanium and Refractory Metals Committee
Material Specification
Electron-Beam Welding For Fatigue Critical ApplicationsAMS2680D (Current)04/14/2025
This specification defines the procedures and requirements for joining metals and alloys using the electron-beam welding process.
AMS B Finishes Processes and Fluids Committee
Material Specification
Aluminum Alloy, Extrusions, 6.3Cu - 0.30Mn - 0.18Zr - 0.10V - 0.06Ti (2219-T8511), Solution Treated, Stress Relief Stretched, Straightened, and Precipitation Heat TreatedAMS4162G (Current)04/14/2025
This specification covers an aluminum alloy in the form of extruded bars, rods, wire, profiles, and tubing up through 2.999 inches (76.2 mm) in diameter, least thickness, or wall thickness and 25 square inches (161 cm2) or less in cross-sectional area (see 8.6).
AMS D Nonferrous Alloys Committee
Material Specification
Aluminum Alloy, Plate, 6.2Zn - 1.9Cu - 2.1Mg - 0.10Zr (7040-T7451), Solution Heat Treated, Stress Relieved, and OveragedAMS4211D (Current)04/14/2025
This specification covers an aluminum alloy in the form of plate 3.001 to 9.000 inches (76 to 229 mm), inclusive, in nominal thickness (see 8.5).
AMS D Nonferrous Alloys Committee
Material Specification
Aluminum Alloy, Extruded Bar, Rod, and Shapes, 5.6Zn - 2.5Mg - 1.6Cu - 0.23Cr (7075-T76(51X)), Solution Heat Treated and OveragedAMS4317C (Current)04/14/2025
This specification covers an aluminum alloy in the form of extruded bars, rods, and shapes up to 4.000 inches (101.60 mm), inclusive, in nominal diameter or least thickness and having a nominal cross-sectional area up to 20 square inches (129 cm2) (see 8.5).
AMS D Nonferrous Alloys Committee
Material Specification
Magnesium Alloy Castings, Permanent Mold, 9.0Al - 2.0Zn (AZ92A-T6), Solution and Precipitation Heat TreatedAMS4484M (Current)04/14/2025
This specification covers a magnesium alloy in the form of permanent mold castings (see 8.6).
AMS D Nonferrous Alloys Committee
Material Specification
Aluminum Alloy, Plate 4.4Cu - 1.5Mg - 0.60Mn (2124-T851) Solution Heat Treated, Stretched, and Precipitation Heat TreatedAMS4101G (Current)04/14/2025
This specification covers an aluminum alloy in the form of plate 1.0 to 6 inches (25.4 to 152.4 mm), inclusive, in nominal thickness (see 8.5).
AMS D Nonferrous Alloys Committee
Material Specification
Steel, Extra High Toughness, Corrosion-Resistant, Bars, Wire, Forgings, Rings, and Extrusions 13Cr - 8.0Ni - 2.2Mo - 1.1Al Vacuum Induction Plus Consumable Electrode Melted Solution Heat Treated, Precipitation-HardenableAMS5934C (Current)04/14/2025
This specification covers an extra high toughness, corrosion-resistant steel in the form of bars, wire, forgings, flash-welded rings, and extrusions up to 12 inches (305 mm) in nominal diameter or least distance between parallel sides (thickness) in the solution heat-treated condition and stock of any size for forging, flash-welded rings, or extrusion.
AMS F Corrosion and Heat Resistant Alloys Committee
Material Specification
Aluminum Alloy, Extrusions, 7.7Zn - 2.4Mg - 1.6Cu - 0.16Cr (7049-T76511), Solution Heat Treated, Stress Relieved, Straightened, and OveragedAMS4159G (Current)04/14/2025
This specification covers an aluminum alloy in the form of extruded bars, rods, wire, profiles, and tubing with a nominal diameter or least thickness (wall thickness of tubing) up to 5.000 inches (127 mm), inclusive (see 8.5).
AMS D Nonferrous Alloys Committee
Material Specification
Titanium Alloy Bars and Forging Stock, 6.0Al - 4.0V Extra Low Interstitial, AnnealedAMS6932D (Current)04/14/2025
This specification covers a titanium alloy in the form of bars up through 10.000 inches (2540 mm) in nominal diameter or least distance between parallel sides, inclusive, with bars having a maximum cross-sectional area of 79 square inches (509.67 cm2), and stock for forging of any size (see 8.7).
AMS G Titanium and Refractory Metals Committee
Material Specification
Steel, Mechanical Tubing, 0.50Cr - 0.55Ni - 0.20Mo (0.25 - 0.33C) (SAE 8630), Aircraft QualityAMS6281L (Current)04/14/2025
This specification covers an aircraft-quality, low-alloy steel in the form of mechanical tubing.
AMS E Carbon and Low Alloy Steels Committee
Material Specification
Steel Tubing, Mechanical Aircraft Quality, 0.50Cr - 0.55Ni - 0.25Mo (0.33 - 0.38C) (SAE 8735)AMS6282L (Current)04/14/2025
This specification covers an aircraft-quality, low-alloy steel in the form of mechanical tubing.
AMS E Carbon and Low Alloy Steels Committee
Material Specification
Aluminum Alloy, Extruded Profiles (2027-T3511) 4.4Cu - 1.2Mg - 0.8Mn - 0.10Zr Solution Heat Treated and Stress Relieved by StretchingAMS4183B (Current)04/14/2025
This specification covers an aluminum alloy in the form of extruded profiles 0.750 to 1.500 inches (19.05 to 38.10 mm) in nominal thickness with a maximum cross-sectional area of 19 square inches (123 cm2) and a maximum circle size of 11 inches (279 mm) (see 8.6).
AMS D Nonferrous Alloys Committee
Material Specification
Aluminum Alloy Discontinuously Reinforced Hot Isostatically Pressed Shapes 2124A/SiC/25p (3 μm) (T1P)AMS4355A (Current)04/14/2025
This specification covers discontinuously reinforced aluminum alloy (DRA) metal matrix composites (MMC) made by mechanical alloying of the 2124A powder and SiC particulate, which is then consolidated by hot isostatic pressing (HIP) into shapes less than 62 square inches (0.04 m2) in cross-sectional area (see 8.12).
AMS D Nonferrous Alloys Committee
Material Specification
Titanium Bars, Wire, Forgings, and Rings, Commercially Pure, 70 ksi (483 MPa) Yield StrengthAMS4921S (Current)04/14/2025
This specification covers one grade of commercially pure titanium in the form of bars, wire, forgings, and flash-welded rings up to 5.000 inches (127.00 mm), inclusive, in nominal diameter or least distance between parallel sides and stock for forging or flash-welded rings (see 8.6).
AMS G Titanium and Refractory Metals Committee
Material Specification
Experimental and Kinetic-Modeling Study of Ammonia/n-Heptane Combustion13-06-03-002004/09/2025
In recent years, researchers have increasingly focused on ammonia–diesel dual-fuel engines as a means of reducing CO2 emissions. Analyzing in-cylinder combustion processes is essential for optimizing the performance of ammonia–diesel dual-fuel engines. However, there is currently a lack of suitable reaction kinetics models for ammonia–diesel engine conditions. In this study, the ignition delay of ammonia/n-heptane mixtures was measured, and a reduced chemical mechanism was developed. Using rapid compression machine (RCM) experiments, the ignition delays of ammonia/n-heptane mixtures with different ammonia energy fractions (AEFs) (40%, 60%, and 80%) were measured. The test pressure ranged from 1.5 to 3.0 MPa, while the temperature ranged from 667 to 919 K, with an equivalence ratio of 1. The results showed that as the AEFs increased, the ignition delay of the premixed mixture also increased. When the AEF was 40%, the ammonia/n-heptane premixed mixture exhibited the negative temperature
Cai, Kaiyuan, Liu, Yi, Chen, Qingchu, Qi, Yunliang, Li, Li, Wang, Zhi
Journal Article
Elongation Prediction of Die-Cast Aluminum Alloy Based on 3D Convolutional Neural Network Model05-18-04-003204/09/2025
This study aims to predict the impact of porosities on the variability of elongation in the casting Al-10Si-0.3Mg alloy using machine learning methods. Based on the dataset provided by finite element method (FEM) modeling, two machine learning algorithms including artificial neural network (ANN) and 3D convolutional neural network (3D CNN) were trained and compared to determine the optimal model. The results showed that the mean squared error (MSE) and determination coefficient (R2) of 3D CNN on the validation set were 0.01258/0.80, while those of ANN model were 0.28951/0.46. After obtaining the optimal prediction model, 3D CNN model was used to predict the elongation of experimental specimens. The elongation values obtained by experiments and FEM simulation were compared with that of 3D CNN model. The results showed that for samples with elongation smaller than 9.5%, both the prediction accuracy and efficiency of 3D CNN model surpassed those of FEM simulation.
Zhang, Jin-sheng, Zheng, Zhen, Zhao, Xing-zhi, Gong, Fu-jian, Huang, Guang-sheng, Xu, Xiao-min, Wang, Zhi-bai, Yang, Yutong
Journal Article
Compatibility between Stability and Curving Ability of Railway Vehicles Using Conventional and Unconventional Bogie Frame Models02-18-03-001404/09/2025
This article analyses the fundamental curving mechanics in the context of conditions of perfect steering off-flanging and on-flanging. Then conventional, radial, and asymmetric suspension bogie frame models are presented, and expressions of overall bending stiffness kb and overall shear stiffness ks of each model are derived to formulate the uniform equations of motion on a tangent and circular track. A 4 degree of freedom steady-state curving model is formulated, and performance indices such as stability, curving, and several parameters including angle of attack, tread wear index, and off-flanging performance are investigated for different bogie frame configurations. The compatibility between stability and curving is analyzed concerning those configurations and compared. The critical parameters influencing hunting stability and curving ability are evaluated, and a trade-off between them is analyzed. For the verification, the damped natural frequencies and mean square acceleration
Sharma, Rakesh Chandmal, Sharma, Sunil Kumar, Palli, Srihari, Rallabandi, Sivasankara Raju, Sharma, Neeraj
Journal Article
A Low-Entry Bus Body Structure Performance under the Conditions of the New Car Assessment Program Frontal Crash Tests09-13-02-000704/09/2025
The New Car Assessment Program (e.g., US NCAP and EuroNCAP) frontal crash tests are an essential part of vehicle safety evaluations, which are mandatory for the certification of civil means of transport prior to normal road exploitation. The presented research is focused on the behavior of a tubular low-entry bus frame during a frontal impact test at speeds of 32 and 56 km/h, perpendicular to a rigid wall surface. The deformation zones in the bus front and roof parts were estimated using Ansys LS-DYNA and considered such factors as the additional mass (1630 kg) of electric batteries following the replacement of a diesel engine with an electric one. This caused stabilization of the electric bus body along the transverse axis, with deviations decreased by 19.9%. Speed drop from 56 to 32 km/h showed a reduction of the front window sill deformations from 172 to 132 mm, and provided a twofold margin (159.4 m/s2) according to the 30g ThAC criterion of R80. This leads to the conclusion about
Holenko, Kostyantyn, Dykha, Aleksandr, Koda, Eugeniusz, Kernytskyy, Ivan, Royko, Yuriy, Horbay, Orest, Berezovetska, Oksana, Rys, Vasyl, Humeniuk, Ruslan, Berezovetskyi, Serhii, Chalecki, Marek
Journal Article
Tire Wear Life Prediction Using Machine Learning Technique2025-01-875704/01/2025
As global warming and environmental problems are becoming more serious, tires are required to achieve a high level of performance trade-offs, such as low rolling resistance, wet braking performance, driving stability, and ride comfort, while minimizing wear, noise, and weight. However, predicting tire wear life, which is influenced by both vehicle and tire characteristics, is technically challenging so practical prediction method has long been awaited. Therefore, we propose an experimental-based tire wear life prediction method using measured tire characteristics and the wear volume formula of polymer materials. This method achieves practical accuracy for use in the early stages of vehicle development without the need for time-consuming and costly real vehicle tests. However, the need for improved quietness and compliance with dust regulations due to vehicle electrification requires more accuracy, leading to an increase in cases requiring judgment through real vehicle tests. To address
Ando, Takashi
Technical Paper
NVH Study of Axial Flux Motor for Electric Propulsion Systems2025-01-856804/01/2025
The advancement of high-performance electrification for electric vehicle (EV) development is continuously pushing the boundaries of electric motor technology. The axial flux motor (AFM) represents a promising application for high-performance EVs, offering potential advantages including up to twice the torque density and a 50% reduction in weight compared to regular IPM radial flux motors. The distinctive "pancake" configuration and high axial forces inherent to AFMs present notable NVH challenges, yet there is a lack of research exploring NVH analysis and risk assessment. In this paper, a 10-pole and 12-slot AFM motor is designed, prototyped, and tested, demonstrating the capability to deliver 320 Nm of peak torque and 140 kW of peak power. A comprehensive finite-element model is constructed, and the orthotropic stator material properties are evaluated using modal test data. The dominant axial stator modes are identified as the source of resonances in the system responses. A three
He, Song, Jensen, William, Forsyth, Alexander, Chang, Le, Zhang, Peng, Gong, Cheng, Yao, Jian, Zou, Yusheng, Fedida, Vincent, Duan, Chengwu, GSJ, Gautam
Technical Paper
Integrated Design for Body in White Fabricated by Additive Manufacturing and its Mechanical Performance Analysis2025-01-861304/01/2025
With the development of additive manufacturing technology, the concept of integrated design has been introduced and deeply involved in the research of body design. In this paper, by analyzing the structural characteristics of the electric vehicle body, we designed a body in white with the additive manufacturing process, and analyzed its mechanical properties through finite element method. According to the structural characteristics of the body, the integrated structure was modeled in three dimensions using CATIA. For the mechanical properties of the body, the strength and stiffness of the body structure were simulated and analyzed based on ANSYS Workbench. The results show that for the strength of the body, the maximum stress of the simulation results was compared with the permissible stress, and the maximum stress was calculated to be less than the permissible stress under each working condition. For the body stiffness, the displacement of the body deformation was used to measure, and
Xu, Cheng, Zhang, Ming, Wang, Tao, Zhang, Tang-yun, Cao, Can, Wang, Liangmo
Technical Paper
Items per page:
1 – 50 of 31791