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The purpose of this paper is to discuss a linear vibratory part feeder for handling brake liners, typical sector-shaped components. Part feeders have been used in the industries for a long time to present the parts in a desired orientation. Berretty et al. (1999) discussed a class of mechanical filters that are capable of removing polygonal sections from the track of the feeder which are referred to as traps. The traps eliminate or reorient the parts until they reach the final desired orientation. A part feeder was developed using traps, to reorient the sector-shaped part to desired orientation. The desired orientation was the most probable natural resting orientation. The trap was mounted on a linear vibratory feeder. The adaptive part feeder developed was capable of identifying the size of the incoming part and adjust the trap to accommodate that. This set-up eliminates the use of different traps for different-sized sector-shaped parts and wastage of productive time in changing the traps for different sizes. A regression model was developed to predict the conveying velocity of part on the feeder.

A part feeder was developed using traps, to reorient the sector-shaped part to desired orientation. Acrylic material was found to be suitable for trap compared to aluminium. The adaptive part feeder developed was capable of identifying the size of the incoming part using proximity sensors. Depending on the size of the incoming part, the track width was adjusted dynamically with the help of a stepper motor, rack and pinion arrangement. A regression model was developed to predict the conveying velocity.

Typical brake liners in the size range of 40-60 mm (radius) were considered for developing the adaptive part feeder. Based on performance studies, the acrylic trap was found better than aluminium traps. The appropriate frequency and amplitude of vibration for maximum conveying velocity of the adaptive part feeder were found experimentally. Regression equation was developed to determine the conveying velocity based on input frequency and amplitude. The regression results were found to be in close agreement with the experimental results.

The developed part feeder is suitable for handling sector-shaped parts only.

This paper demonstrates an inexpensive adaptive part feeding device for handling sector-shaped parts which can be extended for handling other asymmetric parts also.

The purpose of this study is to investigate the influence of commercially available iron–aluminum alloy compared to copper, iron and aluminum powders on the tribological performances of friction composites. The main objective is to replace copper from the friction composite formulations.

In this study, friction composites were fabricated as of standard brake pads using commercially available iron–aluminum alloy and compared to copper powder, iron powder and aluminum powder-based without varying the other ingredients. The brake pads were developed as per the industrial procedure. The physical, mechanical and thermal properties of the developed brake pads were analyzed as per industrial standards. Tribological properties were analyzed using the chase test. Initial speed and deceleration tests in a real-time braking scenario were performed using a full-scale inertia brake dynamometer. Worn surface analysis was done using a scanning electron microscope.

The results indicate that iron–aluminum alloy (mechanomade)-based friction composites possess good physical, chemical, thermal and mechanical properties with stable fade and recovery characteristics due to its composition and flake morphology. During initial speed and deceleration braking conditions, iron–aluminum alloy also showed good tribological behavior.

This paper explains the influence of commercially available iron–aluminum alloy in friction composites in enhancing tribological performance by its composition and flake morphology, which could potentially replace copper in friction composites by solving subsequent problems.

The purpose of this paper is to evaluate experimentally the influence of different surface roughness of the contacting disc on tribological performance of the non-asbestos brake friction material (BFM).

Taguchi method was applied to design an experiment using three different discs of gray cast iron with different surface roughness, which is measured using optical profilometer. These discs were subjected to sliding against pins prepared with the developed non-asbestos BFM, using pin on disc friction and wear monitor.

The experimental results shows that the disc 2 (Ra = 3.77 µm) gives wear of 22.78 µm and coefficient of friction of 0.462, which is recommended for extreme brake performance. Analysis of Taguchi design revealed that the disc surface was most significant parameter among the parameters under study.

During braking, continuous sliding between the BFM and brake disc or drum not only results into wear of BFM but also changes the surface finish of the brake drum or disc. This leads to variation in surface topography of the drum or disc surface with application of brakes, which further affects the characteristics of the BFM.

The tribological performance of BFM depends upon the topography of the surface on which it was sliding. To get best performance of the non-asbestos friction materials, disc having moderate surface finish is recommended. Scanning electron microscope micrographs had shown the different plateaus formed and energy-dispersive X-ray spectroscopy spectra identified presence of different chemical elements prior to sliding of the pins surface over different discs surface topography.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2020-0120/

This study aims to develop magnetic field-controlled friction braking technology, the preparation process of hard magnetic brake friction material was optimized and analyzed in this paper.

NdFeB, a rigid magnetic material, was selected as additive. Magnetic field orientation, a part of material preparation, was added to the preparation process. Experiments investigated the tribological properties of each brake lining sample. The preparation process of the hard magnetic friction material was optimized based on fuzzy theory by using analytic hierarchy process (AHP) methods and SPSS software. The microscopic morphology and the distribution and content of elements of friction lining samples prepared with or without orientation excitation voltage were analyzed by scanning electron microscope and energy dispersive X-ray microanalysis.

The results showed that the tribological properties of brake lining samples could be improved by process optimization and the oriented excitation voltage can effectively improve the properties of the brake lining.

The magnetic field orientation was added into the traditional preparation process, and a set of process parameters with the best tribological properties were obtained through optimization. It is believed that this research will be of great theoretical and practical significance to develop both new brake materials and active control technology of the braking process in the future.

The purpose of this paper is to deal with the tribological study on the brake pads developed using various purity-based graphitized graphite.

This paper deals with developing copper-free brake pads by using graphite as a key lubricant produced using a graphitization process with purity percentages (85, 90 and 95%). The brake pads were developed using traditional manufacturing processes and evaluated for their physical, chemical, thermal and mechanical properties as per industrial standards. Fade and recovery characteristics were analyzed using a full-scale inertia brake dynamometer as per JASO-C-406. The scanning electron microscope was used to analyze the worn surfaces of the brake pads.

The testing findings reveal that the brake pads with 95% graphitized graphite showed better shear strength with good adhesion levels and lesser density, hardness, acetone extract value, loss on ignition and higher porosity. Effectiveness studies of brake pads with graphite (95% graphitized) showed better results at higher pressure speed conditions than others because of better plateau formation and adequate lubrication.

This paper discusses graphitized graphite of different purity influences brake pad's tribological performance by modifying tribo-films and reducing friction undulations.

The purpose of this paper is to underline the future need for OEMs to receive lowSAP, polymer‐ and metal‐free engine oils with high‐viscosity indices and to illuminate for other OEMs the technical feasibility for application of alternative engine oils based on esters or blends of hydrocarbons with esters or polyglycols.

The strategic goal depends technically on the use of intrinsic properties of alternative base fluids, thus substituing some additives, like anti‐wear, extreme pressure and viscosity index improvers. The prone wear resistance of novel triboactive/‐reactive materials enables higher portions of mixed/boundary lubrication generated by oils with a lower viscosity.

Overall, the different bionotox and low‐ash prototype engine oils with reduced additive contents displayed isoperformance regarding the tribological behaviour against cast iron and triboreactive materials. APS‐Ti_n−2Cr₂O_2n−1 displayed an overall wear resistance comparable with grey cast iron with high‐carbon content and liner wear reduction of one order of magnitude when mated with Mo‐based rings. Both tests confirmed the potential for substituing molybdenum‐based rings by APS‐Ti_n−2Cr₂O_2n−1. The most significant reduction in “system wear” down to “zero wear” was demonstrated by mating the APS‐Ti_n−2Cr₂O_2n−1 coated piston rings with smooth machined HVOF‐(Ti,Mo)(C,N) liner coatings.

As lubricants are today not part of the core business of automotive OEMs, the next steps have to be proposed by the petrochemical suppliers. It is recalled here that some OEMs in their history developed and produced lubricants.

The customer will appreciate any increase in longevity resulting in reduced maintenance. The OEM now owns, under increased solicitations, now a future‐oriented tool box in order to respond to environmental and CAFÉ demands with reasonable cost management.

This OEM report displays the complete methodology in order to adopt alternative engine oils in existing engine architectures.

Identifying the most probable natural resting orientation of a part, in automatic handling, helps in the effective design of feeder and orientation devices. For parts with complex geometries and topologies, it is not always intuitively apparent what the natural resting probability of each orientation is. The purpose of this paper is to determine, by theoretical methods, the probability of occurrence of each natural resting orientation of eight different typical sector shaped parts.

Probability of natural resting orientations were found using theoretical methods and drop test. Pearson's χ ² test was used to decide whether to accept or reject the expected data by comparing with the observed data.

Irrespective of dimensions and material, the most probable natural resting orientation was the same. Height of drop was influential in the probability of most probable natural resting orientation.

The research does not include objects with minimum thickness (i.e. 2D objects).

The paper shows that determining the most probable natural resting orientation will help designers to design the part feeders effectively.

This paper aims to deal with the synergistic effect of steel slag-molybdenum disulfide particles on fade-recovery performances of non-asbestos organic friction material.

The brake friction materials were developed by using steel slag and molybdenum disulfide particles as individual and combination in the formulation. The brake friction materials were developed in the form of standard brake pads as per the industrial practice. The physical, mechanical and thermal properties of the developed brake pads were tested as per the industrial standards. The tribological properties were analyzed using the Chase test as per IS2742-Part-4. Worn surface analysis was done using a scanning electron microscope.

The experimental results indicate that the brake pads filled with a combination of steel slag and molybdenum disulfide showed stable friction and less wear rate due to the synergetic nature of abrasive and lubricant.

This paper explains the influence of steel slag and molybdenum disulfide particles as individual and combined in brake pads formulation to enhance the tribological performance by producing stabilized friction with undulations.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-06-2020-0216/

The purpose of the present study is to analyze the wear behavior of developed aluminum hybrid composites under high-stress conditions through developed power law and quadratic equations.

The abrasive wear behavior of Al–Mg–Si (Al 6082) alloy reinforced with hard silicon carbide (SiC) and soft graphite (Gr) particulates fabricated by stir casting route was studied at loads of 5-15 N, sliding distance of 75 m and abrasive grit size of 100-200 μm. The power law and quadratic equations were developed to understand the wear behavior with respect to the load applied and the abrasive grit size. The worn surfaces of the test specimens and grit papers were examined under scanning electron microscope.

The density and hardness of the hybrid composites decreased when compared to Al–SiC composites, whereas the wear properties improved because of the presence of Gr. There was further improvement in the wear properties of the materials because of T6 heat treatment. The change in abrasive wear mechanism was observed at a grit size of 125 μm when traversed from alloy to hybrid composite as indicated in terms of exponents in the power law equation. The worn surfaces of hybrid composite pins were comparable with those of alloy pins.

In the automobile sector, components like cylinder liner, piston, crankshafts, brake drums, etc. also undergo abrasive wear along with sliding against the counter surface in working conditions.

The results prove that better wear resistance was obtained under the abrasion condition.