为进一步拓展火炮身管内膛强化手段,采用粉末冶金技术制备了W-Ni-Fe-Co合金,利用电火花表面沉积技术在CrNi3MoVA钢表面沉积了W-Ni-Fe-Co涂层,同时利用电镀技术在CrNi3MoVA钢表面制备了硬Cr涂层与之进行比较,用纳米压痕仪和摩擦磨损试验机研究了涂层的摩擦磨损性能,并利用XRD、SEM和EDS研究了沉积态和磨损后涂层的相结构、形貌及成分.结果表明电火花沉积W-Ni-Fe-Co涂层由α-W、γ-Fe和NiWO4组成,α-W在涂层中呈白亮带分布;W-Ni-Fe-Co涂层的硬度较电镀硬Cr涂层降低了18％,弹性模量较电镀硬Cr涂层提高了4％;W-Ni-Fe-Co涂层的磨损机制为轻微的粘着磨损,而电镀硬Cr涂层为严重的粘着磨损;CrNi3MoVA钢表面沉积W-Ni-Fe-Co涂层较电镀硬Cr涂层具有明显的减摩耐磨效果,随着摩擦速度的增加,W-Ni-Fe-Co涂层的摩擦系数降低,其原因是磨损表面氧化加剧,氧化物的自润滑作用加大.%In order to further expand the route to harden gun bore,a W-Ni-Fe-Co alloy,prepared by powder metallurgy technology,was used as electrode to electrospark deposit on a CrNi3MoVA steel substrate.Meanwhile,a hard chromium coating was also plated on a CrNi3MoVA steel substrate for comparison.The performance of friction and wear of both coatings was tested by nanoindentor and friction and wear testing machine.Moreover,the phases,morphology and compositions of the deposited and worn coatings were analyzed by XRD,SEM and EDS.The results showed that the W-Ni-Fe-Co coating is composed of α-W distributed as bright band,γ-Fe and NiWO4.The hardness of the W-Ni-Fe-Co coating reduced 18％ than that of the hard chromium coating whilst the elasticity modulus increased 4％.The wear mechanism of the W-Ni-Fe-Co coating is characterized as slight adherent wear while that of the hard chromium coating is severe one.In contrast to the hard chromium coating,the W-Ni-Fe-Co coating electrospark deposited on the CrNi3MoVA steel has an obvious function of antifriction and wear resistance,and what's more,the friction coefficient is reducing with the increase of the friction velocity due to the enhancement effect of oxide self-lubricating with the aggravation of the worn surface.
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