Investigation of The Effect of Solid Lubricant Particle Sizes on Friction and Wear Properties in Friction Composites: An Experimental Case Study with Graphite

Sugözü, İlker | Sugözü, Banu

Friction composites consist of many materials with various properties. Solid lubricant is one of these materials. The task of the solid lubricant in the compo-site is to protect the counter surfaces against wear and to reduce noise and vibra-tion. Typical solid lubricants used in the friction composite are graphite, antimo-ny trisulfide, molybdenum disulfide, copper sulfide, etc. The selection suitable solid lubricants for better braking performance is an important issue, as solid lubricants may decompose at high temperatures, leading to undesirable results. The particle size of the solid lubricant used is at least as important as itself. In this study, the effect of micro and nanoparticle-sized graphite on friction and wear behavior of friction composites was investigated experimentally. ...

Impact of Boric acid and Colemanit addition on tribological behavior and braking performances of brake lining

Sugözü, İlker | Sugözü, Banu

Brake lining is formed as a result of combining different materials. The materials used in the brake lining are an important factor in the brake lining performance. In this study, boric acid and colemanite, one of the boron products with high temperature resistance, were used as brake lining materials. 1%, 3%, 5% and 7% boric acid and colemanite were added to the brake lining content. The tribological properties of the brake linings were examined with a pin-on disc tester. The friction performance increased as the boric acid and colemanite ratio increased in the brake lining content. As the boric acid and colemanite ratio increased, the hardness and density of the brake lining increased, and the wear resistance decreased.

Effect of micro and nano-sized ZrSiO4 particles on the friction and wear properties of polymer matrix composites

Sugözü, Banu | Sugözü, İlker

In this study, the size effect of zircon (ZrSiO4) on the tribological characteristics of polymer matrix friction composites were investigated. Hence, four friction composites containing micro and nano-sized zircon particles (5 and 10 wt%) were developed and produced using powder metallurgy method. Their wear and friction characteristics were examined using a friction-wear test device. The weight loss and specific wear rate were measured and compared with that obtained for microsized zircon particles. The surfaces of samples were analyzed using a scanning electron microscope, and less wear was observed in the samples containing nano-sized zircon particles. The results revealed that the size of abrasive particles plays a key role in enhancing the friction coefficient and friction stability.

Effect of the size on the friction characteristics of brake friction materials: a case study with Al2O3

Sugözü, Banu

Purpose The purpose of this paper is to study the potential of alumina (Al2O3) in nanometer size in automotive brake friction materials. Design/methodology/approach Four brake linings containing alumina differing in particle size (355 µm and 80 nm) and various amount (5 and 10 Wt.%) were designed and produced. The hardness, density and porosity of the samples were measured. All samples were tested on a full-scale brake dynamometer with gray cast iron disc to determine the tribological properties. Detailed examinations on the worn surface were analyzed using a scanning electron microscopy. Findings It was concluded that all performance parameters were beneficially affected because of nano alumina. Originality/value This paper emphasizes the importance of nano-composites in the automotive in...

Effect of Ulexite and Boric acid on the friction characteristics of non-asbestos brake pad

Sugözü, Banu | Sugözü, İlker

Brake pads are used to slow down or stop the vehicle by applying force to the disc surface. The most important parameter in brake pad is friction coefficient. The higher the friction coefficient, the shorter the braking distance will be. Different materials are used to increase the friction performance of the brake pad. A limited number of studies have been carried out to increase the friction performance of brake pads by using boron mineral with high temperature resistance. In this study, brake pad was produced by using boron mineral ulexite and boric acid and its effect on braking performance was investigated. Four different brake pad samples containing 1%, 3%, 5%, 7% ulexite and boric acid were produced by powder metallurgy method. Production parameters are the same for all brake pad sa...

Examination of the Tribological Properties of Brake Pads with Different Hardness Characteristics

Sugözü, Banu | Sugözü, İlker

Brake pads consist of a combination of different materials such as binder, friction adjuster, reinforcement material, lubricant and filler material. Brake pads are produced by using certain proportions of materials containing these components. The tribological properties of the brake pad differ according to the material content of the brake pad composition. The physical properties of the produced brake pads are another factor affecting the tribological properties of the brake pads. In this study, brake pads with different hardness properties were produced. By examining the braking performance of the produced brake pads, its effect on tribological properties has been determined.

Influence of calcium sulfate whiskers on the tribological characteristics of automotive brake friction materials

Sugözü, Banu

Functional fillers enhance the frictional performances of automotive brake friction materials (BFM). The influence of Calcium sulfate whiskers (CaSO4) in BFM’s and its effect as a functional filler on the tribological performances were investigated. Four compositions containing all essential ingredients of BFMs were developed, varying the amount of CaSO4 whiskers (5%, 10% and 15%) and one composition without CaSO4 whiskers. The tribological studies were carried out on an inertia brake dynamometer as per JASO C 406 standard. Addition of CaSO4 whiskers was found to improve the mechanical properties of BFM composites. The inclusion of CaSO4 whiskers enhanced the frictional performance during fade. Surface analysis of the worn pads was carried out to understand the wear mechanism using scannin...

Taşıt fren balatalarında katı yağlacı olarak grafit, molibden disülfit ve Boron nitrit kullanımının frenleme performansına etkisinin araştırılması

Çalışkan, Hasan

Production of boric acid added brake friction composite and the effect of heat treatment on braking characterization

Sugözü, İlker | Sugözü, Banu

Purpose The purpose of this study was to investigate the use of boric acid as a friction modifier material in brake friction composites and to determine the effect of heat treatment applied during production on braking performance. Design/methodology/approach The addition of five different amounts of boric acid was balanced with cashew, which is in the friction modifier material group. The samples were produced in the following order: dry mixing, preforming and hot-pressing. The effect of the heat treatment that can be applied after the hot-pressing process on the braking performance was investigated. The tribological and physical properties of the samples were determined using tests performed according to appropriate standards. The microstructures of the friction surfaces were investigate...