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粉末冶金材料摩擦面上多组分的混合以及第三体的存在,不利于澄清材料中不同组分对摩擦性能的贡献程度.本文采用机械组合方法制备了铜-钢-铝层片式摩擦材料,通过定速摩擦试验机,在干、湿两种条件下,观察了3种组分的摩擦表面微结构随摩擦速度的变化过程,测试了不同条件下的摩擦性能.结果表明:铜良好的塑性和焊合性,易形成与基体黏附性良好的第三体,使表面的粗糙程度增加;钢较高的强度及其氧化物的脆性,形成的第三体流动性好且与基体的结合强度有限,容易发生开裂和脱落;铝形成的富氧化铝的第三体,其颗粒间较差的黏合程度易在表面弥散分布,使表面平整度好.在摩擦速度低于900 r/min条件下,水分的润滑作用使湿摩擦条件下的摩擦系数低于干摩擦;摩擦速度高于900 r/min时,水分的冷却和清理微细第三体颗粒的作用,降低了材料的软化程度和第三体的流动性,使湿摩擦系数大于干摩擦系数.
The mixing of the multi-component and the third body on the friction surface of the powder metallurgy material is not conducive to clarify the contribution of different components in the frictional performance of the material.In this paper, the mechanical properties of copper-steel-aluminum layer friction material The tribological properties of the frictional surfaces of the three components were observed under fixed and wet conditions by using a fixed-speed friction tester, and the tribological properties under different conditions were tested.The results show that the copper Plasticity and weldability, easy to form a good adhesion with the substrate of the third body, so that the surface roughness increases; higher strength of steel and its oxide brittleness, the formation of the third body fluidity and the combination of the substrate The strength is limited, prone to cracking and falling off; aluminum-rich third body of alumina-rich, poor adhesion between the particles easily dispersed in the surface, so that the surface smoothness at a friction velocity of less than 900 r / min conditions Under the lubrication of water, the friction coefficient under wet friction condition is lower than that under dry friction condition. When the friction speed is higher than 900 r / min, the water cooling and cleaning effect of fine third particles reduce the softening degree of the material, Three body Mobility, dry the wet coefficient of friction greater than the coefficient of friction.