| 摘要 |
Drill bits comprise a plurality of steel cutting teeth each having a crest positioned at a tip portion of each tooth, a first flank surface extending from the crest to the cone, a second flank surface opposite the first flank surface and extending from the crest to the cone, and edge surfaces extending from the crest to the cone and interposed between the first and second flank surfaces. Each cutting tooth includes corners that extend from the crest to the cone that are defined by the interface between the first and second flank surfaces and the edge surfaces. A wear resistant surface is positioned on selective tooth surfaces comprising at least the crest and a portion of one or more of the corners. The wear surface is not disposed on at least a surface portion of one of the first and second flank surfaces and the edge surfaces.
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