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论文类型：期刊论文

发表时间：2021-01-09

发表刊物：INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY

卷号：106

期号：1-2

页面范围：191-199

ISSN号：0268-3768

关键字：Atmospheric pressure plasma jet; Minimum quantity lubrication; Grinding; Surface quality

摘要：High-strength alloys have significant application values in aerospace industry due to their excellent mechanical properties. However, grinding of these alloys, which is generally used for precision machining, suffers from problems like high grinding temperature and poor surface quality. Having relatively lower grinding temperature and smaller grinding force, micro-grinding is a high-efficient manufacturing method for precision machining of difficult-to-cut materials. Nevertheless, the side effects induced by current composite grinding methods, such as temperature gradient and chatter marks, tend to be more obvious in the micromachining process. Atmospheric pressure plasma jet (APPJ) can effectively improve metal surface wettability without changing surface structures. On the other hand, minimum quantity lubrication (MQL) can more efficiently cool and lubricate the grinding area. Here, we propose to induce APPJ and MQL cooling media into the micro-grinding area, and adjust the cooling and lubricating characteristics. Quenched GCr15 workpieces are machined under five different conditions (dry micro-grinding, nitrogen jet assisted micro-grinding, APPJ assisted micro-grinding, MQL assisted micro-grinding, and APPJ+MQL assisted micro-grinding), and grinding temperature, grinding force, surface roughness, and surface morphology of workpieces in each group are investigated and analyzed. The results indicate that APPJ can reduce grinding force and that APPJ+MQL microgrinding can obtain surfaces with much better surface quality. Tensile experiments demonstrate that APPJ can reduce material elongation rate and promote material fracture, which contributes to its positive effect on the micro-grinding process. The environmentally-friendly method is expected to have promising application potentials in machining of difficult-to-cut materials.