电火花沉积工艺参数对镍基合金强化层摩擦学性能的影响

摘要

In order to prepare high quality alloy strengthening coatings and improve their tribological properties,the Ni-base.alloy strengthening coatings were prepared by electro-spark deposition.Influence of technological parameters on tribological properties of the Ni-base alloy coatings were studied in detail.The researched results show that the parameters such as electro-parameters,specific strengthening time and flux of argon gas have important effects on tribological properties of the Ni-base alloy coatings;the microstructure of Ni-base alloy strengthening coatings prepared by low value of output voltage(110 V)and relative big capacitance volume(300μF)is dense and have good property of wear resistance;the proper specific strengthening time of 2.5 min/cm~2 and the argon gas flux of 5 L/min were adopted to prepare the Ni-base alloy coatings,which can result in dense and uniform microstructure,decrease friction coefficient.and increase wear resistance.The wear mechanisms of Ni-base alloy coatings are mainly micro-cutting and micro-fracture wear.%为了制备优质的电火花合金强化层,提高强化层摩擦学性能,本文运用电火花沉积工艺,制备了镍基合金强化层,研究了沉积工艺参数对镍基合金强化层摩擦学性能的影响规律.研究结果表明:电参数、比强化时间和氩气流量对镍基合金强化层摩擦学性能产生重要影响;采用低输出电压匹配较高充放电电容量(110 V、300μF)进行表面沉积,所制备的镍基合金强化层组织结构致密,耐磨性高;比强化时间为2.5 min/cm~2时,保护气体氩气的流量应控制5 L/min左右,镍基合金强化层组织均匀致密,气孔率少,可降低摩擦系数,并显著提高强化层的耐磨损性能.镍基合金强化层的主要磨损机理是微观切削和微观断裂磨损.