This paper studies the material aspects of roller cone bits with milled teeth. The research concerns the properties of commercial product overlays provided by the company Glinik Drilling Tools. The analyzed coatings were produced according to the company’s procedures using two surfacing methods: gas welding and plasma transferred arc (PTA) welding. Metallographic observations and chemical composition analyses were carried out. The evaluation criteria in the context of the surfacing application were mechanical properties: hardness, impact strength, and abrasion resistance. The overlays produced by gas welding were characterized by lower hardness, impact strength, and abrasion resistance. The study showed that it differed from the deposit made by the PTA method in the matrix material and in the average size of the tungsten carbides. The dissolution of primary carbides and formation of secondary carbides such as Fe3C and Ni17W3 were found to occur in both surfacing types. This contributes to the increased brittleness of the matrix and reduced wear resistance of the materials.

中文翻译：

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商业化生产的牙轮钻头涂层的性能比较

本文研究了铣齿牙轮钻头的材料方面。该研究涉及 Glinik Drilling Tools 公司提供的商业产品覆盖层的特性。分析的涂层是根据该公司的程序使用两种堆焊方法生产的：气焊和等离子转移电弧（PTA）焊。进行了金相观察和化学成分分析。表面处理应用的评估标准是机械性能：硬度、冲击强度和耐磨性。气焊生产的堆焊层具有较低的硬度、冲击强度和耐磨性。研究表明，它与 PTA 方法沉积的基体材料和碳化钨平均尺寸不同。两种堆焊类型均发现初生碳化物溶解并形成二次碳化物（例如 Fe3C 和 Ni17W3）。这会增加基体的脆性并降低材料的耐磨性。