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采用铜模喷铸法制备出直径为3 mm的原位β-Zr相/Zr非晶基复合材料,对其在干摩擦条件下的滑动磨损行为进行了研究。结果表明,与纯块状非晶合金相比,Zr基块状非晶复合材料的耐磨性能得到明显的改善。复合材料比纯块状非晶合金具有更低的摩擦系数和磨损速度,最低的磨损速度比纯非晶合金的减小48.1%。同时,包含一定体积分数β-Zr相的复合材料表面磨损比纯非晶合金的轻,只有一些浅的犁沟,其磨削小,显示出轻微的磨粒磨损特征,而纯非晶合金的磨损表面呈现出片状、分层、凸起及深的犁沟等特征,磨削大,为严重的磨粒磨损。复合材料低的磨损速度归因于铸态下析出的分布在非晶基体上的韧性β-Zr枝晶相的存在。该相具有较强的承载、塑性变形和加工硬化能力,通过减小界面处非晶基体的应力集中、释放应变能、限制剪切带和裂纹的萌生与扩展、使塑性变形更加均匀等途径提高耐磨性能。
In-situ β-Zr phase / Zr amorphous matrix composites with a diameter of 3 mm were prepared by copper die casting, and the sliding wear behavior under dry friction condition was studied. The results show that compared with the pure bulk amorphous alloy, Zr-based bulk amorphous composite material significantly improved the wear resistance. The composite material has lower friction coefficient and wear rate than the pure bulk amorphous alloy, the lowest wear rate is 48.1% lower than the pure amorphous alloy. At the same time, the composite surface containing a certain volume fraction of β-Zr phase has a lighter surface wear than pure amorphous alloy with only shallow furrows which are less abrasive and show a slight abrasive wear characteristic whereas pure amorphous alloy Wear surface showing flake, layered, raised and deep furrows and other characteristics, grinding large, severe abrasive wear. The low wear rate of composites is attributed to the presence of ductile β-Zr dendrite phase precipitated on the amorphous matrix as-cast. The phase has a strong bearing, plastic deformation and hardening capacity, by reducing the stress concentration at the interface amorphous matrix, the release of strain energy, limiting the shear band and crack initiation and expansion of the plastic deformation more uniform and other ways to improve Wear resistance.