Micro scratch evaluation of rock types - a means to comprehend rock drill wear
Micro scratch evaluation of rock types - a means to comprehend rock drill wear
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DOI：
10.1016/s0301-679x(03)00038-0
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发表时间：
2004-02
影响因子：
6.2
通讯作者：
U. Beste;A. Lundvall;S. Jacobson
中科院分区：
文献类型：
--
作者：
U. Beste;A. Lundvall;S. Jacobson
岩石的钻孔、运输和搬运总是导致与岩石和岩石碎片接触的设备的磨损。岩石通常被认为是相当硬的，接触会导致磨损、侵蚀和点疲劳。然而，工具的磨损机制往往是复杂的，并根据岩石类型的不同而有所不同。要了解岩石钻头中使用的硬质合金的磨损机制，关键是要了解不同类型的岩石如何对硬尖端的严重刮擦作出反应。在划痕试验机中使用半径为10 μm的硬质合金尖端，在0至20 N的递增载荷和10 N的恒定载荷下进行划痕试验。测试的岩石类型是方解石，两种类型的磁铁矿，赤铁矿，锂云母，云母片岩，花岗岩，砂岩和石英跨越平均硬度值从190到1220 HV。在扫描电镜下观察了划痕，并测量了岩石与尖端之间的摩擦系数。此外，还测量了硬质合金刀头的磨损体积。岩石类型不同显着的损伤机制和临界载荷从轻度到更严重的损伤过渡。摩擦行为相应地从相当平滑转变为非常波动。针尖的磨损与岩石的硬度有关，但也受粒度、石英含量和各向同性的影响。全面的岩石钻头磨损的影响，从目前的结果进行了讨论。
Drilling, transportation and handling of rock always result in wear of the equipment that comes into contact with the rock and rock fragments. Rock is normally considered rather hard, and the contact leads to abrasion, erosion and point fatigue. However, the wear mechanisms of the tools are often complex and vary in character depending on the rock type. To understand the wear mechanisms of the cemented carbide used in rock drill bits, it is central to understand how different rock types respond to severe scratching from hard tips. A cemented carbide tip with radius 10 μm was used in a scratch tester at progressive loads of 0 to 20 N and at constant loads of 10 N. The tested rock types were calcite, two types of magnetite, hematite, leptite, mica schist, granite, sandstone and quartz spanning average hardness values from 190 up to 1220 HV. The scratches were investigated in SEM and the friction coefficient between rock and the tip was measured. In addition, the wear volume of the cemented carbide tip is measured. The rock types differed significantly with respect to damage mechanism and critical load for transition from a mild to a more severe damage. The friction behaviour correspondingly shifted from rather smooth to very fluctuant. The wear of the tip was found to be correlated to the hardness of the rocks, but was also influenced by the grain size, the quartz content and isotropy. The implications from the present results on full-scale rock drill wear are discussed.