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This paper aims to overcome the defect of single-source temperature measurement method and improve the measurement accuracy of FTR. The friction temperature rise (FTR) of brake affects braking performance seriously. However, it was mainly detected by single-source indirect thermometry, which has obvious deviations.

A three-point temperature measurement system was built based on three kinds of single-resource thermometry. Temperature characteristics of these thermometry were analyzed to achieve a standard FTR curve. Two fusion-monitoring models for FTR based on multi-source information were established by artificial neural network (ANN) and support vector machine (SVM).

Finally, the two models were verified based on the experimental results. The results showed that the fusion-monitoring model of SVM was more accurate than that of ANN in monitoring of FTR.

Then the temperature characteristics of the three single-source thermometry were analyzed, and the fusion-monitoring models based on multi-source information were established by ANN and SVM. Finally, the accuracy of the two models was compared by the experimental results. The more suitable fusion-monitoring model for FTR monitoring was determined which would be of theoretical and practical significance for remedying the monitoring defect of FTR.

The friction between brake pair causes an intense temperature rise on interface during braking, which affects the braking performance seriously. Therefore, building an accurate testing method for frictional temperature rise (FTR) is a prerequisite.

Facing braking conditions of automobiles, an experimental system for testing of FTR based on preset thermometry method (PTM) was established. The FTR was collected by the PTM and the variation laws as well as the cause of errors were analyzed by experiments. The deviations between tested and real temperature were corrected based on tribology and heat theories. Finally, an online prediction method for FTR was pointed out.

After correction, the temperature curve accords well with the laws of tribology and thermal theories. The corrected FTR at braking end point is approximately equal to the authentic temperature test by hand thermometer.

This study eliminated the hysteresis phenomenon of temperature rise sequence and lays a foundation for online accurate monitoring and warning of brake friction temperature rise. It has important theoretical and practical value for expanding the monitoring and improvement of brake performance.

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.

This paper aims to develop of magnetic field controlled friction braking technology, a novel brake friction material with magnetic was designed and prepared in this paper.

The permalloy, a soft magnetic material, was selected as an additive to design and prepare the magnetic brake material. The friction, wear performance and permeability of each brake pads were investigated by experiments. By choosing the performance of friction coefficient fluctuation, friction coefficient deviation and mean wear rate as optimization parameters, the formulation of the magnetic friction material was optimized based on Fuzzy theory by using analytic hierarchy process methods and SPSS software.

The results showed that the developed soft magnetic friction material has not only superior friction coefficient, permeability and inferior wear rate but also good physical and mechanical properties.

Permalloy powder was added to the formulation of friction material to achieve a new functional friction material with high magnetic permeability. 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.