Various international initiatives on environmental issues and the need to protect the environment are promoting the use of industrial waste in a variety of applications, including automotive brake pads. These studies show that the reuse of industrial waste can help to reduce the environmental impact. The development of environmentally friendly and cost-effective composites for use in a variety of engineering applications is the need of the century. The use of industrial waste in composite production is a possible solution for both problems. In this study, the potential use of talc, quartz and ceramic waste FFC fracture as a friction modifier in brake friction materials and its performance properties in accordance with industry requirements were investigated. The tribological, physical and mechanical properties of the brake pads were measured, and the friction surface morphology was investigated by scanning electron microscopy. According to the results obtained, the highest specific wear rate was observed in the FM3 sample. The FM2 sample with the highest hardness and average friction coefficient showed the lowest wear. FM4, FM5 and FM6 samples with high talc and quartz content exhibited low coefficient of friction characteristics compared to other samples.

With the developing technology, the automotive lighting sector is also changing rapidly. Automotive lighting equipment is produced with more functionality and higher performance. However, with the increase in perfor-mance, undesirable heat generation also increases. Automotive headlights fail or perform poorly when exposed to high heat; therefore, unwanted heat has to be removed. This is accomplished with heat sinks. In this study, four different automotive light-emitting diode (LED) headlights have been designed as channelless, 4-channel, 8-channel, and 12-channel. The designed models were tested numerically at different LED powers (8, 10, 12, 14, and 16W). Thus, the impact of heat sink fin structures on the thermal performance of automotive LED headlights was investigated numerically. The heat dissipation performances of the designs were analyzed using the computational fluid dynamics software SolidWorks Flow Simulation. The simulation results showed that the designed products can be used as LED headlights. As the applied heat power increased, maximum tem-peratures also increased. While a continuous increase in performance was achieved in designs up to 8-channel, slight performance degradation was observed when the number of channels reached 12. As the applied heat power increased, the average temperatures increase whereas thermal resistance (Rth) decreased. From channel-less design to 12-channel design, Rth values decreased from 6.8 °C/W to 5.31 °C/W.

In this study, a fixed automotive friction material content was determined and the mechanical and tribological effects of manufacturing parameters on friction materials were investigated. Parameters; pre-forming time (1-3-5 min) and pre-forming pressure (8-10-12 MPa), hot pressing time (5-10-15 min) hot pressing pressure (8-10-12 MPa) and hot pressing temperature (125-150-175 °C), curing time (4-8-12 h) and curing temperature (120-150-180 °C) were determined. The friction test of the produced samples was carried out under 0.551 MPa pressure and 7 m/s rotation speed for 90 min. In addition, the average COF, friction stability, specific wear rate, density and hardness values of the samples were calculated. According to the results obtained, the average COF value increased as the pre-forming time and pressure increased. The lowest specific wear rate among all specimens was calculated as 7.622x10-6 cm3/Nm in PFP-12 specimen. With the increase in hot pressing time, the tribological properties of friction materials improved. The highest friction stability among all samples was calculated as 79.42% in the HPT-15 sample. Although there was an increase in the average COF value with increasing hot pressing pressure and temperature, the specific wear rates increased in these parameters. The highest average COF value among all samples was obtained in the CT-12 sample with a value of 0.553. The specific wear rate increased with the increase in curing time and temperature. The highest specific wear rate among all samples was calculated 10,743x10-6 cm3/Nm in the CTe-180 sample. Finally, it has been suggested that 3 min for pre-forming time, 12 MPa for pre-forming pressure; 15 min for hot pressing time, 12 MPa for hot pressing pressure, and 150°C for hot pressing temperature; and a curing time of 8 h and curing temperature of 150 °C may be sufficient.

In this study, the effect of sintering temperature on the physical, chemical and tribological effects of sintered automotive friction materials was investigated. Using the powder metallurgy method, 3 different samples were produced with the codes A1, A6 and A11. Mixing, pressing and sintering processes were applied respectively as production steps. Mixing time is 90 minutes, speed is 15 rpm. The pressing pressure is 250 MPa and the duration is 1 min. The sintering temperature was 800 °C and the sintering time was 1, 6 and 11 hours, respectively. The sintering process was carried out in the sintering mold using Argon gas. As the sintering time increased, it was observed that there was an increase in the time-dependent friction coefficients of the samples. Increasing the sintering time also increased the density of the samples. As the sintering time increased, the gap in the sample decreased, as it provided better bonding of the dustsers.

The environmental impactof fossil fuels and their limited availability increase the need for research into alternative energy sources. In this research, pyrolysis oil (PO) was obtained from waste sour cherry kernels. PO cannot be used directly as fuel in diesel engines because of its negative fuel properties, such as low energy density, high viscosity, high water content, and low cetane number. Therefore, PO was blended with diesel at various weight proportions (wt%) using n-butanol (NB) as cosolvent, and 2-ethylhexyl nitrate (2-EHN) as cetane improver. Blended fuels containing 40 wt% diesel i.e., D2 (Diesel 40% / PO 0% / NB 55% / 2-EHN %5), D3 (Diesel 40 / PO 5% / NB 50% / 2-EHN 5%) and D4 (Diesel 40% / PO 15% / NB 40% / 2-EHN 5%) were identified as optimal blend compositions regarding the physicochemical characteristics of fuel. These fuels were tested for engine performance and emission characteristics at engine speeds of 1500, 1800, 2400, 3000 and 3600 rpm under full engine load (10 Nm) in a single-cylinder diesel engine. All data (i.e. cylinder pressure, engine torque and performance changes, heat release rate, and emission characteristics) were recorded using a Kistler KiBox data acquisition system. The engine tests showed a decrease in NOx, HC and soot emissions when blended fuels (D2, D3 and D4) were compared to D1 (Diesel 100% / PO 0% / NB 0% / 2-EHN 0%). The lower NOx emissions in the blended fuels are explained by the PO's water content. Water raises the specific heat capacity of the fuel-air mixture while reducing the internal cylinder temperature. Additionally, the high latent heat of evaporation of n-butanol may contribute to reduce NOx emissions. In addition, the decrease in HC emissions may be caused by the increase in the oxygen ratio of blended fuels, while the decrease in soot emissions may be caused by the low C/H ratio and high oxygen content of blended fuels. To conclude, blends of PO, diesel n-butanol, and 2-EHN can be used as biofuels in diesel engine applications.