دانلود رایگان مقاله انگلیسی طراحی، ساخت و عملکرد یک تستر اصطکاک بالشتک ترمز جدید - نشریه الزویر

ABSTRACT

Determination of the tribological behavior of brake pads under real environmental conditions is an important and critical task which can significantly impact the automotive industry. Most studies simulate or measure the variants by indirect methods and accept them as true results. The new computer-controlled, interactive brake pad friction tester presented in this study was developed for this purpose. The major components of the machine, which are operated simultaneously, include: a proportional pressure-controlled hydraulics power pack, a mechanical transmission system with electromagnetic clutch, and a brake and automation control with SCADA computer analysis interface. Compared to other friction testing machines, a very important innovation of the newly developed friction tester allows for the testing of the brake pad samples and measuring of the noise level both to be performed with high precision under real conditions. Moreover, this friction tester is capable of determining the friction coefficients; wear behavior, temperature, and life intervals of brake pad samples. This novel brake pad system is relatively cheaper and measures effective friction coefficients more accurately. The uncertainty in measurements for friction coefficient and wear rate was approximately calculated as ± 0.0135 and ± 0.170 in all of experiments, respectively. In this study, the machine performance was carried out to evaluate the friction behavior of non-asbestos brake pad samples reinforced with hazelnut shell powder according to the standard brake lining quality control testing procedure (SAE J661).

4. Conclusions

Compared with other friction testing machines, the developed friction tester can be used effectively to determine the cold and hot friction coefficients, noise level and wear rate of brake pads. The frictional performance of the tester depends strongly on its mechanical design, and hydraulic and automation control systems as well as on rigidly applied testing conditions. The equipment and methods used in developing the brake pad friction tester were proven to be quite advantageous in stabilizing the friction coefficients of the brake pad materials, as well as in improving wear resistance. This friction tester could be used to reduce the time required to determine the friction coefficients and wear rate of brake pad materials while considering their testing conditions, a capability which to date has not been available in any other friction testing machines developed on the same scale.

The eco-friendly brake pads reinforced with hazelnut shell dust were successfully produced and tested, based on SAE J661, using the new friction tester. The friction tester, which was developed to determine the tribological behavior of the organic brake pads, was shown to be adequate under the various test conditions usually observed in a real-life scenario, thus allowing for a true evaluation of the brake pad materials. The uncertainty in measurements for friction coefficient and wear rate has added to ± 0.0135 and ± 0.170 to prove the accuracy of the experiments, respectively. Finally, experimental results showed that the developed friction tester provided a significantly reliable and accurate evaluation of the friction and wear performance of the brake pads produced with organic dusts.