| Friction material is the key material of the frictional clutch and arrester. The working principle of frictional clutch and arrester is utilizing the relative movement between the contact surfaces to adjust the friction to generate the relative motion speed or stop the movement, so as to achieve the purpose of transmitting torque. It's mainly used in aircraft, tanks, trains, ships and a variety of mechanical brake, transmitting torque and overload insurance device. Consequently, friction material should have a range of good performance, the traditional friction material is difficult to meet specific application requirements, and only powder metallurgy friction materials due to its own characteristics, such as the high coefficient of friction, high wear resistance, good corrosion resistance, good heat conductivity performance and higher working loads can meet the requirements of the relevant parts, thereby gaining a wide range of applications.In this dissertation, I try to product superior performance and overall well-matched copper-based friction material by powder metallurgy method. In the experiment, using orthogonal test method to optimize the four kinds of auxiliary components Fe, Sn, SiO2 and graphite; First of all, finding the optimal sample ratio friction material in terms of hardness, wear rate of volume friction coefficient and other indicators, and the degree of influence of the elements on each index; secondly, through the calculation of each index test results and judgments, in order to fully measure the experimental results, an integrated balance method for the multi-index analysis of test results that could eventually Integrated optimal combination; and finally, selecting the overall optimization of the final composition and the optimal combinations in terms of hardness, the volume wear and friction coefficient, for the four kinds of materials, do the repeated experiments for comparison. Experimental results show that, after a comprehensive index of all experimental equilibrium analysis,4Sn8Fe10C8SiO2 which is obtained under the conditions of a particular process is the best recipe. under the microscope, the crystal phase morphology of sintered body was found that Sn fully spread, graphite evenly interspersed among the copper matrix to improve the strength of the sintered body, XRD of sintered body and pressed body indicated that the composition was changed, found that sintered body produced CuSn3 and other new phase, these new phase can further enhance the strength and wear properties of the sintered body; the ball plate wear test indicated that all samples at room temperature test conditions, friction coefficients are relatively stable, scanning electron microscopy observation of wear scar morphology of samples in each group was reflected in a slight wear characteristics. In the technology, the paper studies the influence of compacting frequency on physical properties of P/M friction material, it was found that to increase the frequency of press, rather than to further enhance the pressure, to a certain extent, which can improve the hardness of pressed body, but little effect on the density of it, also found that as long as the strict control of a good suppression of technology, for the higher carbon content of mixed powder, as powder bonding is poor, using multiple suppression can increase the intensity of pressed body,avoiding a waste of raw materials.
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