Grey cast iron alloys for brake drum and brake disc applications are being developed with niobium additions and a range of equivalent carbon for commercial, passenger vehicle, and performance applications. The benefit of niobium in cast iron is based on the contribution of strength by matrix refinement for a given carbon equivalence that may permit the direct improvement of wear improvement or allow for an increase in carbon equivalence for a given strength. Proper carbon equivalency and pearlite stabilization contribute to an improved pearlite structure with an optimized distribution of graphite. These structures, when refined with niobium, demonstrate increased service life and reduced wear relative to their niobium-free equivalents as measured by lab dynamometer testing and by on-vehicle testing in passenger bus fleets.
The oxidation of raw materials, such as phenolic resin, in the pad during the braking depends on the temperature but also on the oxygen diffusion capability through the brake pad. Determination of oxygen diffusion is a key point in knowing how deep from the surface tribochemistry can take place. In previous work from RIMSA, it was observed that iron sulphide had been reacted below the surface of the brake pad, suggesting that tribochemistry does not only take place on the surface. The diffusion of oxygen through the pad is a drawback because it induces the matrix decomposition that contributes to intra-stop CoF instability and consequently worsens NVH. This study is focused on determining the oxygen diffusion through brake pads using oxidized iron sulphide particles as indicator parameter. Iron sulphide has a peculiar microstructure (rough microstructure) when it becomes oxide that can be recognized easily, making it a good marker.
Gray cast iron brake rotor experiences substantial wear during the braking and contributes largely to the wear debris emissions. Surface coating on the gray cast iron rotor represents a trending approach dealing with the problems. In this research, a new plasma electrolytic aluminating (PEA) process was used for preparing an alumina-based ceramic coating with metallurgical bonding to the gray cast iron. Three different types of brake pads (ceramic, semi-metallic and non asbestos organic (NAO)) were used for tribotests. Performances of PEA coatings vs. different brake pad materials were comparatively investigated with respect to their coefficients of friction (COFs) and wear. The PEA-coated brake rotor has a dimple-like surface which promotes the formation of a thin transferred film to protect the rotor from wear. The transferred film materials come from the wear debris of the pads. The secondary plateaus are regenerated on the brake pads through compacting wear debris of the pads.
In order to keep the coefficient of friction stable, some additives such as metal sulphides, are included in the brake pads formulation. Previous work from RIMSA has shown that oxidation temperature range of the metal sulphides can be one of the key properties to explain their contribution to the performance and wear of a PAD. This new work is a step forward in the interpretation of the mechanism of sulphides as chemically active additives in the brake pads. Phenolic resin is the matrix of the brake pads and starts to decompose around 300 ºC in presence of oxygen and temperature. In order to establish a connection on between sulphide oxidation and phenolic resin degradation, several studies based on heat treatment of blends of different metal sulphides (Iron sulphide, Tin sulphide and Composite sulphide) with phenolic resin have been done. Then the material evolution was studied with techniques such as TGA - DSC, XRD, IR and SEM - EDS.
A study was performed to compare the performance of automotive friction elements, each manufactured with one of two different coke fillers. Coke #1 is a conventional calcined petroleum coke, and coke #2 a proprietary, calcined coke manufactured from a non-petrochemical feedstock. Subject coke materials were fully characterized, physically and chemically. Both coke materials are similar in their respective physical properties, including morphology, hardness, and crush strength. However, there is a significant difference in the trace metal content of the two materials, with coke #1 containing a higher content of sulfur, calcium, iron, nickel, and vanadium than coke #2. Nickel and vanadium are considered potential environmental hazards. Initial friction element evaluation was performed using the J661 Brake Lining Quality Test Procedure (Chase Test). Ultimately each coke material was formulated into two different automotive brake elements.
Design and Simulation Analysis of Braking system for ATV is carried out with the assistance of Ansys and MATLAB. Heat generated increases the temperature of the disc brake at the rubbing surface resulting in thermal stresses in the components of the braking system. Static, Structural, Thermal, Dynamic, Computational Flow Dynamics, Vibrational & Fatigue Behaviour of Ventilated brake disc Rotor, Hub and Brake Caliper are analysed. Stainless Steel, SS-410 material configuration has been considered for disc brake rotor and results obtained are analysed in terms of performance, longevity and efficiency. Braking efficiency and stopping distance curve are analysed from their characteristics plot. Vibrational Behaviour, Static and Structural Behaviour, Thermal Behaviour, Performance Efficiency, Flow Behaviour of Ventilated Disc Brake Rotor can be easily depicted with respect to Bump and Droop during Acceleration, High Climb and manoeuvrability.
In the last decade, the increasing electrification of road transports has stimulated the look for new braking systems with a high corrosion resistance. This resulted in a fervent research activity behind the development of disc brakes with a reduced corrodibility under demanding tribocorrosive environments. Despite of this, a significant reduction of the cast iron disc corrodibility can be achieved not only by developing variously coated rotors, but also by modulating the intrinsic corrodibility of iron. This can be done by and ad-hoc refining of the cast iron: a) alloying elements concentration; b) microstructure; and c) carbon content and morphology. At this regard, in this contribution, the corrosion properties of a representative ensemble of cast iron specimens are reviewed.
Brake calipers for high-end cars are typically realized using Aluminum alloys, with Silicon being the most common alloying element. Despite the excellent castability and machinability of AlSix alloys, anodization is often necessary in order to provide to AlSix components the required corrosion resistance or when the braking system has to withstand to severe chloride-rich environments . Even if the anodization process is known for almost 100 years, a continuous research and process optimization can lead to the development of anodic layers with enhanced morphological and electrochemical properties, which enable a prolonged resistance of calipers under endurance corrosive tests (e.g. >1000hours Neutral Spray Tests).
Abstract: Attapulgite, a unique clay mineral is a crystalloid hydrous magnesium-aluminium silicate, composed of silicon oxide, aluminium oxide, magnesium oxide, iron oxide etc. having formula Mg5Si8O20(HO)2(OH2)4•4H2O. Its structure is somewhat between laminated and chain structure having very high surface area and porosity. Its magnesium silicate structure resembles a brick wall with every second brick missing. This leaves elongated porous channels that are highly absorbent. Its fibers were proven to be excellent substitute for asbestos in brake-pads. Hardly anything in details is reported on its exact role in controlling tribo-properties of friction materials (FMs) especially Cu-free FMs. Hence, in this work a series of brake-pads with five types was formulated and developed with increasing amount of attapulgite (0, 5, 10 and 15 wt. %) by compensating with inert barite particles in Cu-free FMs.
The development and production of resonators on the charged air side of combustion engines require profound base of knowledge in designing, simulating and the production of such parts in different materials (aluminum, copper, stainless steel and technical plastic). As combustion engines are under constant discussion, this existing knowledge base should be used for other applications within and outside the automotive industry. Very quickly it became apparent that new challenges often require completely new solutions, designs and materials to meet the requirements of flow noise reducing parts. For example, for clean air applications mufflers based on “special treated foams” and “meta-materials” can be introduced. These materials offer new potentials for tuning of the frequency range and allow improved broad banded flow noise attenuation. Such parts are named “Resabtors” in order to take respect of the different flow noise attenuation principles resonation and absorbing.
In order to mitigate the effect of fossil fuels on global warming, biodiesel is used as drop in fuel. However, in the mixture of biodiesel and diesel, soft particles may form. These soft particles are organic compounds, which can originate from the production and degradation of biodiesel. Further when fuel is mixed with unwanted contaminants such as engine oil the amount soft particles can increases. The presence of these particles can cause malfunction in the fuel system of the engine, such as nozzle fouling, internal diesel injector deposits (IDID) or fuel filter plugging. Soft particles and the mechanism of their formation is curtail to understand in order to study and prevent their effects on the fuel system. This paper focuses on one type of soft particles, which are metal soaps. More precisely on the role of the short chain fatty acids (SCFA) during their formation. In order to do so, aged and unaged B10 and B100 were studied.
In automobiles, the most commonly used braking system is disk brake. The disk is the important component in either slowing or stopping the vehicle.When a brake is applied, there occurs a friction between the brake pad and the disk. Due to this action, a large amount of heat is generated. In order to reduce the generated heat, different sandwich structures were designed. The main objective is to analyze the thermal behaviour of the sandwich ventilated structures of different profiles and compare their results and suggest the suitable ventilation structure that highly influences the convective heat transfer of the brake disc under on-road rigorous braking conditions. The chosen brake disc material is titanium alloy. The profiles which are analyzed are X-core, Corrugated, Round O-core and Honeycomb. The heat transfer and the pressure drop characteristics of the sandwich structures were found with one face sheet heated by constant heat flux and cooled by forced air convection.
An industrial air compressor is finding a wide range of usage in manufacturing and assembly areas. The intake valve body is one of the major parts in the industrial air compressor which serves numerous functions like regulating the amount of air into the compressor for pressurizing and prevents the backflow of oil. The main intern of our proposed work is to design and conduct Finite Element Analysis (FEA) in air intake valve body casing part with commercially used metallic material of LM6 aluminium alloy and proposed hybrid polymer composite. The proposed polymer material Polyphthalamide (PPA) reinforced with 30wt% glass fiber and 5% Poly tetra fluro ethylene (PTFE) hybrid composites were prepared through the injection moulding route and the obtained tested responses were taken as input data for the further analysis.
Nd: YAG Laser Welding Process (LWP) is the most efficient method commonly used for the joining of different kinds of materials, whether it can be a sheet or plate.LWP in general,uses high power density, frequency and travel speed or feed rate as primary process parameters in order to perform a joining process across the metals. This paper investigates the effect on free vibrational characteristics for Stainless Steel 304 (SS 304) joints which are reinforced with Al2O3 micro particles processed by dual side (welding performed on the top and bottom surface of sheets) Nd: YAG LWP. The inclusion of micro particles was inserted directly across the weld pool region, by fabricating drills with a constant gap between each drilled holes. Totally 12 samples were fabricated with different laser power, travel speed and by keeping the frequency level as constant for all the experiments.
In automobile industries, the usage of natural fiber composites (NFC) becomes one of the most inevitable materials in engineering applications because of its better properties such as less expensive, high strength to weight ratio and stiffness. In recent days door trim panels, wheel arch, rear hatch, roof liner and bonnet insulation in vehicles were fabricated by NFC. Once the vehicle attains ELV (end-of-life vehicles) metals from the vehicle were recycled but the NFC’s were not recycled and dumped as scrap. Hence the main objective of the present research was to recycle the NFC waste as reinforcement in the hemp/epoxy composite. This work examines the effect of reinforcing the composite waste in hemp fiber in various weight percentages (0, 5, 10 and 15). The mechanical characteristics such as tensile, flexural, impact and hardness were carried out for the prepared composite as per ASTM standards.
Wire Electrical Discharge Machining (WEDM) is a contemporary approach of material removal which is conceived from the concept of Spark Erosion Machining process. Wire Spark Erosion Machining which is known as WEDM, predominantly employed for removing material from hard materials and also especially used for making intricate shapes on any electrically conductive work material with irrespective of the hardness. Composite materials offers improved mechanical properties depends upon the constituents to be added. Graphene is identified as outstanding reinforcing element which provide support to enhance the desired properties of aluminium metal matrix composites in a considerable manner. In this present exploration an analysis has been performed on WEDM of Al-GNP composites. Pulse on time (µs), pulse off time (µs) and servo voltage (V) are deemed as input process parameters in this present exploration.