多尺度表面织构陶瓷刀具的制备及其切削性能研究

发布时间：2018-06-04 13:58

本文选题：陶瓷刀具 + 干切削　；参考：《山东大学》2016年博士论文

【摘要】：本文提出了多尺度表面织构陶瓷刀具的设计概念和设计思路,通过对陶瓷刀具材料表面微织构和纳织构的制备工艺研究,结合固体润滑技术,成功制备出多尺度表面织构陶瓷刀具,系统研究了多尺度表面织构陶瓷刀具的摩擦磨损特性及切削性能,分析并揭示了该刀具的减摩作用机理。分析了采用纳秒激光和飞秒激光在陶瓷刀具材料表面诱导微织构和纳织构的形成机制；同时建立了织构表面与光滑平面接触的静态模型,从理论上分析了表面织构在摩擦接触过程中的减摩机理和表面织构刀具对切削力和切削温度的影响。分析表明,表面织构能够有效地减小实际接触面积,从而减小接触界面的摩擦,降低表面的摩擦接触温度。表面织构刀具能够有效地降低切削过程中的切削力和切削温度。提出了多尺度表面织构陶瓷刀具的设计概念和设计思路,研究了多尺度表面织构陶瓷刀具的制备方法和制备工艺。通过开展纳秒激光和飞秒激光在陶瓷刀具材料表面加工微织构与纳织构的工艺试验,优化得到最佳的微织构和纳织构激光加工工艺参数。采用纳秒激光制备微织构的最佳工艺参数为：泵浦电压为19.5 V,扫描速度为5 mm/s,重复频率为6 kHz,扫描1遍；对应的微织构宽度约为50μm,深度约为43μm。采用飞秒激光制备纳织构的最佳的工艺参数为：能量为1.75μJ,扫描速度为500μm/s,扫描1遍；对应的纳织构周期约为750 nnm,深度约为150 nm。采用最佳激光加工参数同时结合固体润滑技术制备出了多尺度表面织构陶瓷刀具。通过摩擦磨损试验对微织构陶瓷刀具材料表面摩擦磨损特性进行了研究。结果表明,干摩擦条件下,微织构试样(AT)增大了摩擦系数和摩擦温度,但减小了表面的磨粒磨损和粘结。微织构与固体润滑技术协同作用(AT-W)能够有效地减小摩擦系数、摩擦温度和表面的磨损与粘结；与未织构表面试样(AS)相比,其摩擦系数降低了70-80%,摩擦温度降低了40-50%。这主要是由于摩擦作用引起了微织构内部固体润滑剂转移到摩擦接触界面形成润滑膜,从而有效地减小了摩擦,降低了摩擦温度；同时,微织构能够有效地收集磨屑,减少表面的磨粒磨损和粘结。通过摩擦磨损试验对纳织构陶瓷刀具材料表面摩擦磨损特性进行了研究。结果表明,纳织构试样(TS)相比未织构试样(SS)能够有效地减小表面摩擦和粘结,其摩擦系数降低了6-13%。纳织构涂层试样(TCS)减摩效果最为明显,与未织构涂层试样(SCS)和未织构试样(SS)相比,TCS试样摩擦系数分别降低了16-38%和85-93%。分析了TCS试样减摩润滑机理：一方面,纳织构提高了涂层与基体的结合强度,延长了涂层的磨损寿命。另一方面,纳织构能够存储固体润滑涂层,摩擦过程中,纳织构中的润滑涂层在摩擦挤压作用下,有效地转移到摩擦接触界面,形成连续的润滑薄膜,从而减小了摩擦与粘结。研究了未织构陶瓷刀具(AS)、未织构表面涂层陶瓷刀具(AS-L)、纳织构涂层陶瓷刀具(AN-L)和多尺度表面织构涂层陶瓷刀具(AT-L)干切削45淬火钢时的切削性能。结果表明,AT-L刀具能够最有效地改善刀具的切削性能。与AS刀具相比,AT-L刀具三向切削力降低了25-40%,切削温度降低了10-20%；前刀面刀-屑接触区平均摩擦系数降低了17-22%,刀-屑接触长度减小了8-17%,刀-屑接触区平均切应力减小了11-13%,但其刀尖正应力和刀-屑接触区平均正应力增大了7-11%。在切削速度为200 m/min时,AT-L刀具寿命与AS刀具相比提高了14.7%。揭示了AT-L刀具切削过程中的减摩机理。切削过程中,AT-L刀具能够在刀-屑接触界面形成一层润滑薄膜,从而减小刀-屑接触界面间的摩擦。微纳织构的存在能够有效地减小刀-屑接触长度,降低粘结区长度占总刀-屑接触长度的比例。同时纳织构增加了涂层与基体的结合强度,微织构能够收集磨屑和磨损掉的润滑涂层,进而能够减小前刀面磨粒磨损和提供二次润滑作用。因此,AT-L刀具能够有效地减小摩擦与磨损是固体润滑剂、微织构与纳织构共同作用的结果。
[Abstract]:In this paper, the design concept and design ideas of multi-scale surface textured ceramic tools are proposed. Through the study of the micro texture and the preparation of the nanoscale on the surface of the ceramic tool materials and the solid lubrication technology, the multi scale surface textured ceramic tools are prepared successfully. The friction and wear characteristics of the multi-scale surface textured ceramic tools are systematically studied. The mechanism of the friction reduction of the cutting tool is analyzed and revealed. The formation mechanism of the micro texture and the texture of the nanosecond laser and femtosecond laser on the surface of the ceramic tool material is analyzed, and the static model of the contact between the texture surface and the smooth plane is established, and the friction contact process of the surface texture is analyzed theoretically. The mechanism of friction reduction and the influence of the surface texture tool on the cutting force and the cutting temperature. The analysis shows that the surface texture can effectively reduce the actual contact area, thus reduce the friction of the contact interface and reduce the friction contact temperature of the surface. The surface texture tool can effectively reduce the cutting force and the cutting temperature during the cutting process. The design concept and design ideas of multi-scale surface textured ceramic tools are designed. The preparation and preparation techniques of multi-scale surface textured ceramic tools are studied. The optimum microtexture and nanoscale laser are optimized by the process experiments of nanosecond laser and femtosecond laser on the machining of micro texture and texture on the surface of ceramic tool materials. The optimum parameters of micro texture by nanosecond laser are: the pump voltage is 19.5 V, the scanning speed is 5 mm/s, the repetition rate is 6 kHz, the scanning is 1 times. The corresponding micro texture width is about 50 mu m and the depth is about 43 u M. to prepare the nanosecond texture by the femtosecond laser. The energy is 1.75 um J, scanning. The velocity is 500 mu m/s and scanning 1 times; the corresponding nanoscale period is about 750 NNM, the depth is about 150 nm., and the multi-scale surface textured ceramic tool is prepared by using the best laser processing parameters and solid lubrication technology. The friction and wear characteristics of the micro texture ceramic tool material surface are studied by friction and wear test. Under dry friction conditions, the micro texture sample (AT) increases the friction coefficient and the friction temperature, but reduces the abrasive wear and bonding of the surface. The synergistic effect of micro texture and solid lubrication (AT-W) can effectively reduce the friction coefficient, the friction temperature and the wear and bond of the surface. Compared with the non textured surface sample (AS), the friction coefficient decreases. Low 70-80%, the friction temperature decreases 40-50%., which is mainly due to the friction caused by the transfer of the solid lubricant inside the micro texture to the friction contact interface to form a lubricating film, which effectively reduces friction and reduces the friction temperature. At the same time, the micro texture can effectively collect the debris and reduce the wear and adhesion of the surface. The friction and wear properties of nano textured ceramic tool materials were studied by friction and wear tests. The results showed that the nano texture specimen (TS) could reduce the surface friction and adhesion effectively compared with the untextured specimen (SS), and the friction coefficient reduced the most obvious effect of the 6-13%. nano textured coating sample (TCS), and the untextured coating sample (SCS) and the untextured coating sample (SCS). Compared with SS, the friction coefficient of TCS samples decreased by 16-38% and 85-93%. respectively. The friction reduction mechanism of TCS samples was analyzed. On the one hand, the nano texture enhanced the bonding strength of the coating and the matrix and extended the wear life of the coating. On the other hand, the nano texture could store the solid lubrication coating, and the lubrication in the nano texture during the friction process. Under friction extrusion, the coating is effectively transferred to the friction contact interface to form a continuous lubricating film, thus reducing friction and bonding. The non woven ceramic tool (AS), the non woven surface coated ceramic tool (AS-L), the nanoscale coated ceramic tool (AN-L) and the multi scale surface textured ceramic tool (AT-L) dry cutting are 45 Quenched. The cutting performance of fire steel shows that AT-L tool can improve cutting performance most effectively. Compared with AS tool, AT-L tool three reduces cutting force by 25-40%, cutting temperature decreases 10-20%, the average friction coefficient of knife chip contact area decreases 17-22%, knife chip contact length decreases 8-17%, tool chip contact area averages The shear stress is reduced by 11-13%, but the average stress of the tip positive stress and the knife chip contact area increases 7-11%. at the cutting speed of 200 m/min, and the lifetime of the AT-L cutter is improved by 14.7%. to reveal the mechanism of the friction reduction in the cutting process of the AT-L tool. In the cutting process, the AT-L knife can form a layer of lubrication in the interface of the knife chip contact. The film, thus reducing the friction between the contact interface of the knife chip, can effectively reduce the length of the knife chip contact and reduce the length of the bond area to the length of the total chip contact. At the same time, the texture of the nano texture increases the bonding strength of the coating and the matrix, and the micro texture can collect the wear debris and wear the lubricating coating, and then reduce the length of the coating. The knife surface is abrasive and provides two lubrication. Therefore, AT-L tools can effectively reduce friction and wear as a result of the interaction of solid lubricants, micro texture and texture.
【学位授予单位】：山东大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TG711

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