The Reaction Mechanism Of The In Situ Synthesis Of Cu / Of Fes Material And Performance

The metal-matrix solid self-lubricating materials as a group of high performance materials have caused great interest in the world due to their attractive tribological properties,it is very significance in saving energy prolonging use life and improving reliability. Crystal structure of FeS is hexagonal structure, so it is a good solid lubricating material.This thesis fabricated Cu/FeS composite material by in-situ method, and the ? raw materials were CuS copper alloy and Cu, the outcome which was analyzed by XRD and EDAX had three substances including Cu FeS and Fe₂O₃, we researched the corresponsive mechanism by means of thermodynamic and kinetics .We firmly that the reaction would spontaneous process, at the same time ,we calculated Gibbs energy for every oxidation reaction of Cu and Fe, then explained why Fe₂O₃ was fabricated. We analyzed the kinetics process and calculated the activation energy of reaction by DTA and measure the conductivity during 5%FeS reactive process.We fabricated three specimens which the mass percent of FeS were 5% 10% 15% respectively in theory. With the mass percent increasing of FeS, the relative density and conductivity declined but the hardness increased .The specimens were processed such as hot press and extrusion, and we analyzed the microstructure and performance at different stage. From the microstructures, we known that grain of FeS assembled at first and distributed dispersion gradually. Compared with hot press, the relative density conductivity and hardness of the specimen increased with extrusion. The stress test indicated that the max stress declined but the stretch with the true strain. 15%FeS specimen which true strain 7.2 was hot pressed, and then was analyzed by TEM, the results proved that the grain of FeS is sphericity , there was a great deal of dislocation in the specimen. We also studied the friction-wear property of it.We researched the change of wear quantity and friction coefficient in different conditions which included load velocity and hardness, at the same time, we studied the wear mechanism of Cu/FeS composite material. The wear quantity and friction coefficient would increase with load but velocity, the specimen which was anneal and hardness reduced would make the wearing more rapidly. The wear mechanism of Cu/FeS composite material were induced by adherence and grain.