Improving the tool life of steel threaded drill bits by borozing method

With a growing population and developing technologies, necessity of underground resources available to mankind for supply need of humankind guided humankind to research on formation of new material. In the past two decades, with production of advanced engineering materials such as drilling-cutting tool tungsten carbide, obtained tool performance but could not prevented increasing cost. This work includes a research on expandability of tool lives by coating with nano-size boron powder on steel tipped drilling tools which is cheaper than tungsten carbide tools and widely used in shallow drilling applications. In this work, steel tipped drilling tools coated shorter time according to conventional boronizing methods as 1000oC 30 min, 45 min, 60 min, 75 min, 90 min, and 105 min. with nano-boron powder by a thermochemical coating method. Optical microscopy, SEM, X-ray, microhardness and microabrasion tests were applied to boronized samples and compared to the sample without any processing applied. In XRD test result, FeB, Fe2B, CrB Cr2B, NiB phases was found in boride film. In boronizing process result, it was observed that borid film thickness and hardness values increased with increasing boronizing time. Boronizing process increased surface hardness approximately 5 times. In abrasion test result, it was observed that abrasion resistance increased with increasing boronizing time and hardness correspondingly.