陶瓷刀具表面微织构的激光加工工艺基础及刀具磨损机理研究

发布时间：2018-04-25 23:38

本文选题：激光加工 + 陶瓷刀具　；参考：《广东工业大学》2015年硕士论文

【摘要】：陶瓷刀具的快速磨损是制约淬硬钢等难加工材料高速切削加工的关键问题,高性能的表面微织构具有良好的减磨性能,该技术应用于陶瓷刀具表面将会极大的提高陶瓷刀具的切削性能。因此,本文针对激光参数对陶瓷刀具表面微织构制备的影响规律,以及表面微织构不同参数对陶瓷刀具切削性能的影响规律这两大核心问题开展了研究,具体工作如下：(1)采用ANSYS对355nm紫外激光加工陶瓷刀具过程进行仿真研究,分析了不同激光能量密度与扫描速度下,355nm紫外激光对陶瓷刀具材料去除的影响规律,与实验研究的结果作对比,同时为实验研究提供合适的参数选择范围。(2)采用单因素实验研究方法分析了不同激光参数对微织构制备的影响规律,结果表明：355nm紫外激光加工陶瓷刀具表面微织构的过程中,随着激光能量密度的增加,微织构的宽度逐渐增加,最终趋于25μm,微织构的深度也线性增大；激光扫描速度影响到材料在单位时间内接受到激光脉冲的个数,随着激光扫描速度的增加,微织构的宽度基本不变,微织构的深度逐渐减小；随着激光扫描次数的增加,微织构的宽度有所波动,整体呈现逐渐减小的趋势,微织构的深度线性增大；激光重复频率不仅影响光斑的重合度,还会改变单脉冲能量的大小,当频率在10kHz～30kHz之间时,随着频率的增加,微织构的宽度逐渐减小,微织构的深度逐渐增大；当频率在30kHz～ 40kHz之间时,随着频率的增加微织构的宽度和深度都急速减小；当频率在40kHz～ 50kHz之间时,随着频率的增加微织构的宽度和深度逐渐增加。最终选取了合理制备陶瓷刀具表面微织构的激光加工工艺参数。(3)采用ABAQUS有限元仿真软件对陶瓷刀具切削淬火钢的过程进行仿真研究,分析了微织构的置入对刀具切削温度和刀具应力分布的影响规律。根据仿真结果,选取不同的微织构形貌参数进行切削实验,并为刀具磨损机理的研究奠定理论基础。(4)采用单因素实验研究方法分析了不同激光参数对微织构制备的影响规律,结果表明：不同形貌微织构陶瓷刀具切削淬火钢后,横向微织构陶瓷刀具前刀面的磨损区域最小、磨损中心到切削刃的距离最远、磨损深度最小,并且横向微织构陶瓷刀具后刀面的磨损量最小；随着微织构深度的增加,刀具前刀面磨损区域逐渐增大、磨损中心到切削刃的距离越来越近、磨损深度逐渐增加,刀具后刀面的磨损量逐渐增大：随着微织构间距的增加,刀具前刀面磨损区域逐渐增大、磨损中心到切削刃的距离先增加后减小、磨损深度逐渐增加,刀具后刀面的磨损量逐渐增大；随着微织构宽度的增加,刀具前刀面磨损区域逐渐增大、磨损中心到切削刃的距离越来越近、磨损深度逐渐增加,刀具后刀面的磨损量逐渐增大。(5)采用SEM精细化的观察分析了刀具前、后刀面的磨损状况,研究了表面微织构陶瓷刀具的磨损机理。结果表明：微织构深度过大时,切削过程中刀具强度降低进而导致刀具破损；微织构间距过大时,切削过程中有效作用的微织构数量减少将会导致刀具磨损增加；微织构宽度过大时,切削过程中二次切削将会导致刀具磨损增加；横向微织构可以有效减少刀具与切屑的摩擦作用,减少刀具磨损。
[Abstract]:In this paper , the influence of different laser parameters on the cutting performance of ceramic cutting tools is studied by means of ANSYS . The influence of different laser energy density and scanning speed on the cutting performance of ceramic cutting tools is studied .
the laser scanning speed affects the number of laser pulses received by the material in a unit time , and the width of the micro - texture is basically unchanged as the laser scanning speed increases , and the depth of the micro - texture is gradually reduced ;
As the number of laser scanning increases , the width of the microtexture fluctuates , the overall presentation gradually decreases , and the depth of the micro - texture increases linearly ;
The repetition frequency of laser affects not only the coincidence degree of the spot , but also the size of the single pulse energy . When the frequency is between 10 kHz and 30 kHz , the width of the micro - texture gradually decreases as the frequency increases , and the depth of the micro - texture gradually increases ;
When the frequency is between 30 kHz and 40 kHz , the width and depth of the micro - texture decreases rapidly as the frequency increases ;
The effects of different laser parameters on the cutting temperature and the stress distribution of cutting tools were studied by means of finite element simulation software . The experimental results show that the wear area of the front rake face of the transverse micro - textured ceramic cutter is the least , the wear depth is the minimum , and the wear of the cutter face of the transverse micro - texture ceramic cutter is the minimum .
With the increase of the micro - texture depth , the wear area of the rake face of the cutter gradually increases , the distance between the wear center and the cutting edge is gradually increased , the wear depth is gradually increased , the wear area of the rake face of the cutter gradually increases as the micro - texture distance increases , the distance between the wear center and the cutting edge is increased , the wear depth is gradually increased , and the wear amount of the cutter face of the tool is gradually increased ;
With the increase of the width of the micro - texture , the wear area of the rake face of the cutter gradually increases , the wear depth increases gradually , and the wear depth of the tool flank is gradually increased .
When the micro - texture space is too large , the reduction of the number of micro - textures which are effective in the cutting process can increase the wear of the tool ;
when the micro - texture width is too large , the secondary cutting in the cutting process can increase the wear of the tool ;
The transverse micro - texture can effectively reduce the friction between the cutter and the chip and reduce the wear of the cutter .

【学位授予单位】：广东工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TG71

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