(1. 南昌大學 機電工程學院 材料加工工程系，南昌 330031;
2. 南昌市輕合金材料制備與加工重點實驗室，南昌 330031)
摘 要: 利用MMD-1型銷盤式磨損試驗機，采用OM、SEM和EDS研究不同負載對Sr變質(zhì)ADC12合金的摩擦磨損性能的影響，并探究其與合金顯微組織及力學性能的關(guān)系。結(jié)果表明:當添加0.05%Sr(質(zhì)量分數(shù))時，合金顯微組織中共晶Si相以顆粒狀或纖維狀均勻分布在晶界，富鐵相則呈短棒狀，此時合金力學性能最佳，且同一負載下其磨損量和摩擦因數(shù)均最低。當負載為100N時，因受到嚴重擠壓變形，合金表面氧化膜發(fā)生破壞;基體合金以塑性屈服和嚴重剝層磨損為主要磨損機理;而當Sr添加量為0.05%時，合金的磨損程度最低，以粘著磨損和磨粒磨損為主要磨損機理，其摩擦磨損性能最優(yōu)異。
關(guān)鍵字: Sr變質(zhì);ADC12合金;摩擦磨損;磨損機理
（1. Department of Materials Processing Engineering, School of Mechanical and Electrical Engineering,
Nanchang University, Nanchang 330031, China;
2. Key Laboratory of Light Alloy Preparation & Processing in Nanchang City, Nanchang 330031, China）
Abstract:The effect of applied load on the friction and wear properties of Sr modified ADC12 alloys, and its relationship with microstructure and mechanical properties were investigated by MMD-1 pin-on-disc wear testing machine, OM, SEM and EDS. The results show that, in the microstructure of alloy modified with 0.05%Sr (mass fraction), eutectic Si phases distribute uniformly at grain boundaries in morphologies of particle-like or fiber-like, and shape of Fe-rich intermetallics transforms to short rod-like, giving rise mechanical properties to the highest. Also the alloy wear volume and friction coefficient reach to the lowest under invariable load. At 100 N, oxide films on worn surface are broken due to the serious extruded deformation. Plastic yielding and severe delamination are mainly in the matrix alloy, while adhesive and abrasive wear characterize in the modified alloy with 0.05%Sr. The wear degree of the latter one is the minimum, and its friction and wear properties are the optimal.
Key words: Sr modification; ADC12 alloy; friction and wear; wear mechanism
