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基于逆向工程学的仿生非光滑齿轮表面耐磨性的研究
Study on Anti-wear Ability of Bionics Non-smooth Gear Surface Based on the Reverse Engineering
【作者】 许小侠;
【导师】 韩志武;
【作者基本信息】 吉林大学 , 农业机械化工程, 2004, 硕士
【摘要】 摩擦阻力广泛存在于实际生产和我们的生活中,运动副之间的摩擦将导致零件表面材料的逐步丧失或迁移,即形成磨损,磨损是金属零件失效的三种主要原因(磨损、腐蚀、疲劳)之一。据不完全统计,能源的1/3到1/2消耗于摩擦与磨损;对材料来说,约80%的零件失效是磨损引起的。磨损不仅消耗能源和花费材料、降低设备运转效率,而且加速设备报废、导致部件更换频繁,造成极大的经济损失。因此,由磨损而带来的诸多问题越来越引起学术界的广泛重视。齿轮传动过程中,其主要失效形式是齿轮磨损,大小齿轮根部的磨损量较大,特别是球磨机的传动齿轮、发电厂磨煤机的传动齿轮等大模数齿轮,这些齿轮尺寸都很大,加工制造工艺复杂,更换一个新齿轮需要十万元,甚至几十万元,给企业和社会造成了巨大的经济损失。为此,迫切需要采用一种新型、有效的方法提高传动齿轮的抗磨损和承载能力,这是本文的关键之所在。因此,针对以上问题,本文具体做了以下几方面的工作:1. 对齿轮表面进行了逆向工程学研究。利用3D SCANNER激光扫描仪对齿轮表面进行了三维测量,由于考虑到实际扫描中对整体扫描的困难以及齿轮结构的对称性,所以本文只是对齿轮进行了局部扫描,然后利用Surfacer软件对点云进行初步处理,采用人工法进行噪声去除,从去除噪声以后的点群中取出一个扫描效果比较好的齿形作为研究对象,采用由曲面拼接的方法生成单个齿形的曲面模型,再利用该软件中的镜像功能获得了齿轮整体曲面模型,最后,将重构的曲面导入到UG软件中,获得齿轮三维几何实体模型。2. 从仿生学原理的角度出发,设计了九种不同的大小及间距的凹坑形仿生非光滑表面形态,由于非光滑结构单元为微观非光滑,几何单元小、形态复杂,传统的机械加工不能满足加工要求,所以采用激光表面处理技术来加工其表面非光滑结构。所有试件的加工均是在JHM-1GY-100B型激光数控加工机上完成的,通过激光表面重熔强化处理技术使表面层获得比<WP=81>较硬而耐磨的组织结构和非光滑形态。3. 对光滑与仿生非光滑齿轮模型试件进行了耐磨性的试验研究。由于主要是要研究其微观摩擦学性能,所以利用微观摩擦学实验机测试其摩擦磨损特性。利用试验优化设计理论,采用正交试验设计安排试验方案,通过探索性试验,确定了本试验中影响磨损的四个主要因素及其相应水平,即:非光滑单元大小(300、250、200)、距离(550、450、350)、速度(140、110、80)、负荷(13N、10N、7 N)。本试验中,各种试件的摩擦磨损的时间均为90分钟,其耐磨的性能通过体积磨损率和摩擦系数来评定,体积磨损率利用XTJ-30型体视显微图像电脑分析系统测出磨痕宽度,再利用公式ΔV= a和K=计算得到,其中,a为往复滑动距离;d为试件表面磨痕宽度;r为对磨件GCr15钢球的半径;L为试验时所加的负荷;T为试验时间,摩擦系数由微观摩擦学试验机记录的摩擦力与负荷之比得到。通过光滑与仿生非光滑齿轮模型试件耐磨性的对比试验可知,光滑试件的体积磨损率较大,说明非光滑表面形态的确具有耐磨的性能,其耐磨性提高值在7.222%~135.389%之间。分析了仿生非光滑表面耐磨的机理,一方面是由于激光处理重熔强化的作用,另一方面则是仿生非光滑表面形态的效应。同时对几种不同大小及间距的凹坑形非光滑形态的耐磨性也进行了对比,发现几种形态参数中,凹坑4是最耐磨的,其形态参数是凹坑大小为300,距离是350,分析其耐磨的原因主要是在微观的范围内,由于凹坑4与其它几种形态相比,其形态参数相对较大,因此,由以上两点带来的耐磨程度更强,所以最耐磨。最后,运用多元线性回归正交试验设计对具有非光滑表面形态的齿轮模型试件的试验结果进行了回归分析,获得了其体积磨损率和摩擦系数与各试验因素间的回归方程: <WP=82>其中,、、、分别代表大小、距离、速度、负荷。通过回归方程可以看出各试验因素对试验指标的影响程度。对于体积磨损率来说,各因素对其影响程度由大到小依次是、、、,即负荷、速度、大小、距离,可以看出,随着负荷和转速的增加体积磨损率逐渐增大;对于摩擦系数来说,各因素对其影响程度由大到小依次是、、、,即负荷、速度、距离、大小,与体积磨损率相反,随着负荷和转速的增加,摩擦系数逐渐减小,通过回归方程还可以看出,因素间的交互作用与各因素单独作用相比都是很微小的,这在以后的研究中可以不予考虑。本文通过采用激光表面重熔强化技术,将仿生非光滑耐磨技术应用于齿轮模型试件的表面,使其耐磨性得到显著的提高,为齿轮行业长期存在的齿面磨损严重的问题提供了一个行之有效的方法,本研究对于进一步将仿生非光滑形态用于其它机构及零部件的表面,以期提高其承载能力及耐磨性具有重要的实际参考价值。
【Abstract】 Wear resistance extensively exists in the actual production and our life. Abrasion is one of the three kinds of main reasons (abrasion, corrosion, fatigue) of invalidation of metal parts. According to incomplete statistics, about 1/3 or 1/2 of the consumption of the energy is caused by friction and abrasion. About 80% invalidation of components is caused by abrasion for materials. Abrasion not only consumes the energy and materials and decreases the equipment efficiency, but also accelerates the equipments discard and causes the parts replacement frequently and big economy loss. Therefore, abrasion is causing more and more extensive academic attention of many fields. In the process of gear driving, its main invalidation form is abrasion. The abrasion on the gear root is bigger, especially for the driving gears of ball mill, the driving gears of power plant, which have big modulus. These gears are very big, and it is complicated to be manufactured. To replace such a gear need RMB100,000, even than RMB100,000, which leads to enormous economy loss for the enterprise and society. Therefore, a new and valid method of improving anti-wear ability and carrying capacity is required, which is the key research content in the paper. The research works are as follows: 1. To study the gear surface based on the reverse engineering. 3D measurement of gear surface was completed with 3D SCANNER laser scanner. Considering the difficulty of scanning the whole parts and the structural symmetry of gear, the partial scanning of gear was done. The data point cloud was processed with Surface software, and the noise was deleted with the artificial method. The good gear model in the deleted data point cloud was selected as research object, and was made up a curve surface to form a curve surface model, then the function of mirror image was used to get the whole gear model and input the model to the UG software. Finally, the 3D geometry <WP=84>entity model of gear was got.2. From the view of bionics principle, nine kinds of bionic non-smooth concave surfaces with different sizes and distance of non-smooth units were designed. For small geometry unit and complex form of non-smooth units, the traditional machinery manufacturing methods cannot satisfy to the requirement, and the laser texturing method was adopted to manufacture the non-smooth surfaces. All samples were processed and completed in the JHM-1GY-100B laser NC manufacturing machine. 3. The experimental investigations of anti-wear ability for smooth and bionics non-smooth gear model samples were completed. The micro-tribology tester was adopted to study the micro-tribology characteristics of non-smooth samples. Considering the experimental optimum design theory and orthogonal design, the main four factors and levels effecting the friction and abrasion were confirmed, namely, size(300μm, 250μm, 200μm), distance(550μm, 450μm, 350μm), velocity(140 rpm,110 rpm,80 rpm), load(13 N,10 N,7 N). In this experiment, the wear time of every sample was 90 minutes, and the anti-wear ability of the samples was assessed by the rate of volume abrasion and the friction coefficient. The rate of volume abrasion was measured by the wear width from the XTJ-30 microscope system, and calculated by ΔV= a and K= . Where, a is back and forth sliding distance, d is the wear width, r is the radius of GCr15 steel ball, L is the experimental load, and T is the wear time. The friction coefficient was confirmed by the ratio of the friction force and experimental load. It was found in the contrast wear experiments of smooth and bionics non-smooth gear model samples that the rate of volume abrasion of the smooth sample was bigger, and the increasing vale of volume abrasion rate is between 7.222% and 135.839%. The anti-wear mechanism of bionics non-smooth <WP=85>surface was due to the re-melting strengthening of laser and bionics non-smooth surface morphology. At the same time, the anti-wear ability of several non-smooth concave surfaces with different size and distance of non-smooth unit was compare
【Key words】 Reverse engineering; surface software; bionics; non-smooth surface morphology; gear; wear; abrasion; anti-wear ability; laser texturing; micro-tribology tester; experimental optimum design; orthogonal experiment design; multi-element linear regression; volume abrasion rate; friction coefficient;
- 【网络出版投稿人】 吉林大学 【网络出版年期】2004年 04期
- 【分类号】TH132.4
- 【被引频次】13
- 【下载频次】525