The wear level of diamond composite sheets can be determined step-by-step through three levels: visual observation, performance change assessment, and precise measurement. The specific methods are as follows:
1. Preliminary Visual Assessment: Visual inspection or a low-magnification magnifying glass can be used to directly observe the appearance characteristics and preliminarily classify the wear level:
Slight Wear (Still Usable): Only the diamond cutting edge is slightly rounded, with no chipping, chipping, or delamination. The wear is less than 1 mm, and the ground surface is smooth without obvious cracks.
Moderate Wear (Requires Attention): The cutting edge is noticeably flattened, the diamond layer thickness is reduced by more than 1/3, there are localized minor chipping but no detachment, and the drill bit's drilling efficiency begins to decline.
Severe Wear (Must Replace): The diamond layer is almost completely worn away, exposing the cemented carbide matrix, or there is chipping, chipping, or delamination of the diamond layer. Alloy residue or voids appear in the weld pits of the drill bit body, making normal cutting impossible.
2. Indirect Judgment Through Construction Performance: Performance changes during drilling/machining are the most direct reflection of wear levels:
Sudden Drop in Drilling Speed: Under the same drilling pressure and rotational speed, a mechanical drilling speed that is more than 30% lower than that of a new drill bit is most likely due to excessive wear of the composite cutting edge, requiring machine shutdown and inspection.
Abnormal Drilling Vibration/Deviance: Irregular vibration of the drill bit and deviation of the drilling trajectory indicate uneven wear of different composite cutting edges, with some teeth already worn and ineffective, unable to bear force evenly.
Decreased Cutting Accuracy: In tool machining, increased surface roughness and excessive dimensional errors indicate severe wear of the composite cutting edge, requiring re-sharpening or replacement.
