| Carbon fiber/phenolic?CF/PF?resin friction composites are widely used in transportation,aviation,aerospace and military fields due to their excellent wear resistance,low noise and so on.However,the application of carbon fiber/phenolic resin friction composites is restricted due to its strong brittleness,fatigue resistance and poor thermal conductivity.To solve this problem,and further improve the tribological performances of carbon fiber/phenolic resin friction composite,the filler of core-shell particles and burning surface oxidation of carbon fiber was introduced.We prepared the carbon fiber/phenolic resin and research thermal conductive,thermal stability,the interlayer bonding properties and tribological performance of the friction composites.The research content of this paper is as follows:The modified?-Si3N4?m-SiN@PANI?core-shell particles was coated by polyaniline,which was prepared by self-stable dispersion polymerization.The effect of filler content on thermal conductivity and tribological performances of carbon fiber/phenolic resin friction composite was studied.The experimental results show that when the core-shell content reaches 2.0 wt%,the thermal,conductive,friction and wear properties of the friction composite reach the best,which are:3.164 Wm-1k-1?5.33×10-66 S/m and 1.13×10-8mm3/Nm.PF/?2.0wt%?m-SiN@PANI/CF composite wear rate is up to 68.08%lower than that PF/CF composite.And its friction coefficient is 48.48%lower than that PF/CF composite.By preparing silicon nitride??-Si3N4,?-Si3N4?fillers with different crystal cores,the properties of carbon fiber/phenolic resin friction composites reinforced by the fillers were studied,and the effects of different crystal core fillers on the properties of friction composites were analyzed.The core-shell filler prepared by?-Si3N4 and?-Si3N4 improves the tribological properties,thermal conductivity and other related properties of carbon fiber/phenolic resin friction composites to different degrees.The wear rate of PF/m-?-SiN@PANI/CF composite is 1.13×10-88 mm3/Nm,the friction coefficient is 0.168;The wear rate of PF/m-?-SiN@PANI/CF composite is 2.25×10-88 mm3/Nm,and the friction coefficient is up to 0.248.At the same time,the wear rate of the friction composite reinforced by?-Si3N4 is calculated,and the wear rate of the friction composite reinforced by?-Si3N4 is as low as 1.13×10-88 mm3/Nm.The mechanism of the influence of crystal shape on the friction of composites was systematically studied.By controlling the burning time and other conditions,the surface of carbon fiber was activated and the mechanical properties of carbon fiber were nondestructive.Experimental results show that the tensile strength of carbon fiber burned for 10 min only decreases by1.80%,which has no impact on the later application.After 10 min of burning,the friction and wear properties of the carbon fiber reinforced composites have been improved correspondingly,up to 1.47×10-88 mm3/Nm and 89.23 MPa. |
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