Browse Topic: Elastomers
Hydrogenated nitrile butadiene rubbers (HNBR) and their derivatives have gained significant importance in automotive compressed natural gas (CNG) valve applications. In one of the four-wheelers, CNG valve application, HNBR elastomeric diaphragms are being used for their excellent sealing and pressure regulation properties. The HNBR elastomeric diaphragm was developed to sustain CNG higher pressure However, it was found permanently deformed under lower pressures. In this research work, number of experiments was carried out to find out the primary root cause of diaphragm permanent deformation and to prevent the failure for safe usage of the CNG gas. HNBR diaphragm deformation investigation was carried out using advanced qualitative and quantitative analysis methods such as Soxhlet Extraction Column, Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Optical Microscopy (OM), Scanning Electron Microscopy (SEM), and Thermogravimetric Analysis (TGA). For
The increasing adoption of electric vehicles (EVs) has intensified the demand for advanced elastomeric materials capable of meeting stringent noise, vibration and harshness (NVH) requirements. Unlike internal combustion engine (ICE) vehicles, EVs lack traditional masking noise generated by the powertrain. In the automotive industry, the dynamic stiffness of elastomers in internal combustion engines has traditionally been determined using hydraulic test rigs, with test frequencies limited to a maximum of 1,000 Hz. Measurements above this frequency range have not been possible and are conducted only through computerized FE or CAE calculation models. Electric drive systems, however, generate distinct tonal noise components in the high-frequency range up to 10,000 Hz, which are clearly perceptible even at low sound pressure levels. Consequently, the dynamic stiffness characteristics of elastomers up to 3,000 Hz are critical for optimizing NVH performance in EVs. This study focuses on high
Rubber components are an important part of the suspension system of high-speed trains, and the complex nonlinear characteristics of rubber parts have a significant impact on the vehicle dynamic performance. This paper establishes a nonlinear dynamics model of the liquid composite swivel arm positioning node, which can reflect the dynamic stiffness and dynamic damping characteristics of the rubber components that change nonlinearly with the frequency and amplitude, and also has a fast calculation speed. The vehicle dynamics simulation model considering the longitudinal stiffness nonlinear characteristics of the arm node is established, and the influence of the stiffness nonlinearity of the liquid composite arm positioning node on the dynamic performance of the vehicle, such as straight-line stability and curve passing ability, is studied in depth through numerical simulation.
Researchers at the University of California San Diego have developed a soft robotic skin that enables vine robots that are just a few millimeters wide to navigate convoluted paths and fragile environments. To accomplish this, the researchers integrated a very thin layer of actuators made of liquid crystal elastomer at strategic locations in the soft skin. The robot is steered by controlling the pressure inside its body and temperature of the actuators.
From sorting objects in a warehouse to navigating furniture while vacuuming, robots today use sensors, software control systems, and moving parts to perform tasks. The harder the task or more complex the environment, the more cumbersome and expensive the electronic components.
This SAE Aerospace Information Report (AIR) provides a general description of methods for hardness testing of O-rings including factors which affect precision and comparison of results with those obtained in standard tests.
This specification covers a high temperature, compression set and fluid resistant fluorocarbon (FKM) rubber in the form of sheet, strip, tubing, extrusions, and molded shapes for aeronautical and aerospace applications.
This specification covers a silicone (PVMQ) rubber in the form of sheet, strip, tubing, extrusions, and molded shapes.
This specification covers a fluorosilicone (FVMQ) rubber in the form of molded rings.
This specification covers an acrylonitrile-butadiene rubber in the form of molded rings, compression seals, O-ring cord, and molded-in-place gaskets for aeronautical and aerospace applications.
Melanoma testing could one day be done at home with a skin patch and test strip with two lines, similar to COVID-19 home tests, according to University of Michigan researchers. Developed with funding from the National Institutes of Health, the new silicone patch with star-shaped microneedles, called the ExoPatch, distinguished melanoma from healthy skin in mice.
In today’s medtech landscape, innovation isn’t just about what a device does — it’s about how reliably and cost-effectively it gets to market. As devices grow smaller, smarter, and more user-centered, materials like liquid silicone rubber (LSR) play a bigger role in enabling performance, comfort, and compliance. From implantables to connected wearables, LSR is helping engineers meet growing design and usability demands. As demand for the material grows, so do the pressures on supply chains, including launch timelines, increased regulatory scrutiny, and rising technical complexity.
Researchers have developed a soft, thin-film auditory brainstem implant (ABI). The device uses micrometer-scale platinum electrodes embedded in silicone, forming a pliable array just a fraction of a millimeter thick. This novel approach enables better tissue contact, potentially preventing off-target nerve activation and reducing side effects.
This specification covers one type of a non-melting, heat-stable silicone compound, for use in high tension electrical connections, ignition systems, and electronics equipment, for application to unpainted mating threaded or non-threaded surfaces, and as a lubricant for components fabricated from elastomers. This compound is effective in the temperature range from -54 °C (-65 °F) to +204 °C (400 °F) for extended periods. This compound is identified by NATO symbol S-736 (see 6.5).
This standard establishes the dimensional and visual quality requirements, lot requirements, and packaging and labeling requirements for O-rings molded from AMS7274 rubber. It shall be used for procurement purposes.
This SAE Aerospace Standard (AS) provides a standardized test procedure that can be used to evaluate material capability in a dynamic sealing application. This procedure will be utilized by applicable elastomer material specifications which are used for production of O-rings and other seals. This specification is applicable to the dynamic testing requirements for aerospace elastomer parts utilizing materials conforming to AMS7XXX series specifications, user specifications, or print on a Purchase Order (PO) that calls out this document for aerospace applications. This procedure is intended for testing NBR. Other elastomers may have different requirements which will require a separate procedure.
Mechanical light detection and ranging (LiDAR) units utilize spinning lasers to scan surrounding areas to enable limited autonomous driving. The motors within the LiDAR modules create vibration that can propagate through the vehicle frame and become unwanted noise in the cabin of a vehicle. Decoupling the module from the body of the vehicle with highly damped elastomers can reduce the acoustic noise in the cabin and improve the driving experience. Damped elastomers work by absorbing the vibrational energy and dispelling it as low-grade heat. By creating a unique test method to model the behavior of the elastomers, a predictable pattern of the damping ratio yielded insight into the performance of the elastomer throughout the operating temperature range of the LiDAR module. The test method also provides an objective analysis of elastomer durability when exposed to extreme temperatures and loading conditions for extended periods of time. Confidence in elastomer behavior and life span was
Road noise caused by road excitation is a critical factor for vehicle NVH (Noise, Vibration, and Harshness) performance. However, assessing the individual contribution of components, particularly bushings, to NVH performance is generally challenging, as automobiles are composed of numerous interconnected parts. This study describes the application of Component Transfer Path Analysis (CTPA) on a full vehicle to provide insights into improving NVH performance. With the aid of Virtual Point Transformation (VPT), blocked forces are determined at the wheel hubs; afterward, a TPA is carried out. As blocked forces at the wheel hub are independent of the vehicle dynamics, these forces can be used in simulations of modified vehicle components. These results allow for the estimation of vehicle road noise. To simulate changes in vehicle components, including wheel/tire and rubber bushings, Frequency-Based Substructuring (FBS) is used to modify the vehicle setup in a simulation model. In this
High-frequency whine noise in electric vehicles (EVs) is a significant issue that impacts customer perception and alters their overall view of the vehicle. This undesirable acoustic environment arises from the interaction between motor polar resonance and the resonance of the engine mount rubber. To address this challenge, the proposal introduces an innovative approach to predicting and tuning the frequency response by precisely adjusting the shape of rubber flaps, specifically their length and width. The approach includes the cumulation of two solutions: a precise adjustment of rubber flap dimensions and the integration of ML. The ML model is trained on historical data, derived from a mixture of physical testing conducted over the years and CAE simulations, to predict the effects of different flap dimensions on frequency response, providing a data-driven basis for optimization. This predictive capability is further enhanced by a Python program that automates the optimization of flap
This specification covers a synthetic rubber in the form of sheet, strip, tubing, molded shapes, and extrusions. This specification should not be used for molded rings, compression seals, molded O-ring cord, and molded-in-place gaskets for aeronautical and aerospace applications
Electric vehicles (EVs) are particularly susceptible to high-frequency noise, with rubber eigenmodes significantly influencing these noise characteristics. Unlike internal combustion engine (ICE) vehicles, EVs experience pronounced variations in dynamic preload during torque rise, which are substantially higher. This dynamic preload variation can markedly impact the high-frequency behaviour of preloaded rubber bushings in their installed state. This study investigates the effects of preload and amplitude on the high-frequency dynamic performance of rubber bushings specifically designed for EV applications. These bushings are crucial for vibration isolation and noise reduction, with their role in noise, vibration, and harshness (NVH) management being more critical in EVs due to the absence of traditional engine noise. The experimental investigation examines how preload and excitation amplitude variations influence the dynamic stiffness, damping properties, and overall performance of
Lead-filled aprons are currently used for atomic number (Z)-grade radiation shielding in the medical industry to protect personnel from hazardous gamma radiation. These apron garments are made with lead-filled elastomeric sheets encased in polymeric fabrics and are both heavy and bulky to meet necessary shielding requirements. In addition, there are environmental safety concerns surrounding disposal of these garments due to their lead content. An innovator at NASA Langley Research Center has developed a novel method for making thin, lightweight radiation shielding that can be sprayed or melted onto common textiles used in clothing such as cotton, nylon, polyester, Nomex, and Kevlar.
Material solutions for thermal management, protection and assembly. Today's ADAS designers are adding more electronic components and redundant computing systems to printed circuit boards (PCBs). These heat-generating electronic assemblies are installed in enclosures that provide environmental protection, but the high heat generated by high-performance computing systems can degrade ADAS performance or cause device failure. Not all thermal management materials can withstand temperatures up to 200 C (392 F), and most do not retain their flexibility at elevated temperatures. This creates a problem when PCB components expand and contract at different rates due to mismatches in their coefficients of thermal expansion.
This material type has resistance to hot air, but generally has poor resistance to fuels and lubricants, but usage is not limited to such applications. Each application should be considered separately. This material type has a typical service temperature range of -85 to 500 °F (-65 to 260 °C). The operating temperature range of the material is a general temperature range, but the presence of particular fluids and design parameters may modify this range. Recommendations on the material selection are based on available technical data and are offered as suggestions only. Each user should make his own tests to determine the suitability for his own particular use.
In the holiday movie The Grinch, makeup artists are reported to have spent several hours each day encasing Jim Carrey’s face with prosthetics to create the iconic grumpy, green-furred creature. Such elaborate prosthetics, often made possible by materials like silicone rubbers, may have now found an unexpected yet beneficial biomedical engineering application, according to a new study from Texas A&M University.
A team led by Emily Davidson has reported that they used a class of widely available polymers called thermoplastic elastomers to create soft 3D printed structures with tunable stiffness. Engineers can design the print path used by the 3D printer to program the plastic’s physical properties so that a device can stretch and flex repeatedly in one direction while remaining rigid in another. Davidson, an assistant professor of chemical and biological engineering, says this approach to engineering soft architected materials could have many uses, such as soft robots, medical devices and prosthetics, strong lightweight helmets, and custom high-performance shoe soles.
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