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铝基碳化硅颗粒增强复合材料(SiCp/Al)有许多优异的特性,但其加工非常困难,限制了该种材料在工程中的应用。旋转超声辅助磨削加工非常适合中、高体分SiCp/Al复合材料的加工。针对增强体体积分数45%、增强颗粒尺寸3μm、基体材料A12的SiCp/Al复合材料进行了实验研究,分析了加工表面形貌、表面粗糙度和切削力随切削参数的变化规律。实验结果表明,工件加工表面质量较高,表面粗糙度Ra值在0.131~0.340μm之间;切削过程平稳,轴向切削力Fz值在23.33~51.31N。 相似文献
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使用聚晶金刚石(PCD)刀具,对碳化硅颗粒增强铝基复合材料(SiCp/Al)进行高速铣削加工,研究了加工表面质量及切屑的形成机制。结果表明:刀具进给波纹、工件材料塑性侧流、刀具-工件相对振动和增强颗粒去除过程留下的孔洞、微裂纹、基体撕裂等是SiCp/Al复合材料高速铣削加工表面的主要形成机制;增大切削速度、使用冷却液、降低增强颗粒体积分数、减小增强颗粒尺寸均有助于提高加工表面质量;切屑形态为不均匀锯齿状,增强颗粒体积分数、热处理状态等对切屑形成有显著影响,绝热剪切、孔洞/微裂纹动态形成和扩展是切屑的主要形成机制。 相似文献
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SiCp/Al复合材料高速铣削的有限元仿真研究 总被引:1,自引:0,他引:1
《工具技术》2013,(9):34-38
运用有限元分析软件ABAQUS建立了三维斜角铣削模型,对SiCp/Al复合材料的的高速铣削过程进行模拟。首先分析了切削过程中SiCp/Al复合材料的应力、应变的分布规律,然后分析了不同等效切削厚度对切屑形状和温度场的影响,最后分析了切削参数对切削力的影响规律。铣削过程的有限元模拟为SiCp/Al复合材料高速铣削加工的工艺参数优化、刀具参数的合理选择提供了参考。 相似文献
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由于SiCp/Al颗粒增强复合材料具有高比模量、高比强度、耐磨性好、耐高温和导热导电性能良好等优异性能,使其在工程应用中成为了传统金属的精良替代品。针对体积分数为45%的SiCp/Al颗粒增强复合材料进行切削研究,建立切削仿真模型,从应力场的分布情况、颗粒的断裂与破碎机理以及切屑表面的裂纹扩展等方面对切削机理进行仿真分析,并通过铣削实验进行了验证。结果表明,颗粒的断裂与破碎主要发生在剪切区和工件与切屑的分离面,同时由于颗粒的存在会使切屑表面产生微裂纹,微裂纹的扩展是影响切屑表面形态的重要因素。 相似文献
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S. T. Huang L. Zhou X. L. Yu Y. Cui 《The International Journal of Advanced Manufacturing Technology》2012,62(5-8):487-493
In this paper, high-speed milling experiments on silicon carbide particle reinforced aluminum matrix (SiCp/Al) composites with higher volume fraction and larger particles were carried out using polycrystalline diamond (PCD) tools at dry and wet machining conditions. For comparison, a TiC-based cermet tool was also used in milling the same workpiece material at very low speed. Worn PCD and cermet tools were measured and extensively characterized by scanning electron microscopy at different machining conditions. Furthermore, the effect of cutting distance on milling force and surface roughness were also investigated. The results showed that the main tool wear mechanism in machining of this type of material was abrasion on the flank face, and it was verified that the TiC-based cermet tool was not suitable for machining SiCp/Al composites with higher volume fraction and larger particles due to the heavy abrasive nature of reinforcement. 相似文献
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Ching-Yang Lin 《Machining Science and Technology》2020,24(1):65-95
AbstractThis study designed an automatic cutting feed adjustment system for computer numerical control (CNC) turning machine tools, which integrate the operational characteristics of cutting force control and chatter suppression control to shorten the machining time and maintain the quality of workpieces. The setting of appropriate machining conditions (such as cutting feed, spindle speed and depth of cut) to consider both machining quality and efficiency often causes difficulties for machine tool operators. Therefore, this study uses cutting force control to design an automatic cutting feed adjustment method for cutting tools, and then, the chatter suppression control design is used to modify the cutting force command to suppress cutting chatter. The experimental results of the CNC turning machine tool show that the use of the cutting force control to adjust the cutting feed can shorten the machining time; however, the cutting chatter results in larger surface waviness on the workpiece surface. When the cutting force command is properly modified by actuating the chatter suppression control, the workpiece shows better surface roughness with prolonged machining time. Therefore, the cutting tests demonstrate that the proposed system is feasible for satisfying the machining requirements of the manufacturing processes of mechanical parts for high speed and high accuracy. 相似文献
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A. Meena M. El Mansori 《The International Journal of Advanced Manufacturing Technology》2013,69(9-12):2833-2841
Dry machining is being recognized as ecological machining due to its less environmental impact and manufacturing cost. However, the choice of dry machining is mainly influenced by the workpiece material properties, machining operation and cutting conditions. The recent emergence of austempered ductile iron (ADI) can be considered a significant economic advantage to the increasing industrial demand for cost- and weight-efficient materials. However, due to its microstructure-induced inherent properties, ADI is considered hard-to-machine material. Thus, the dry drilling of ADI is investigated in this paper. The ADI material used in the present study is produced using an innovative process route for near net shape casting production. Drilling experiments are conducted on a DMU80P Deckel Maho five-axis machining centre using PVD-coated carbide tools under dry cutting environment. The dry drilling of ADI under different cutting conditions is evaluated in terms of specific cutting force and tool wear analysis. The influence of cutting conditions on chip morphology and surface roughness is also investigated. The experimental results revealed that the combination of the low feed rate and higher cutting speed leads to the higher mechanical and thermal loads on the tool's cutting edge, resulting in higher specific cutting force values. This behaviour is further supported by the chip morphology analysis, which revealed the formation of segmented chips at higher cutting speed with segment spacing increase with an increase in feed rate. Depending upon the cutting parameters, different modes of tool failures including crater wear, flank wear, chipping, breakage and built-up edge were observed. Surface roughness analysis revealed the influence of tool wear and chip morphology on the machined surface finish. 相似文献
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Jan C. Aurich Marco Zimmermann Stefan Schindler Paul Steinmann 《The International Journal of Advanced Manufacturing Technology》2016,82(5-8):1317-1334
Aluminum metal matrix composites (Al-MMCs) are two-phase high-performance materials. The reinforcement of aluminum alloys enhances the properties of the composite material but leads to poor machinability. The required mechanical work for machining is mostly dissipated into heat. Considerable generated quantities of heat are therefore expected when machining Al-MMCs due to the poor machinability of these composite materials. The machine tool, the tool, and the workpiece are thus subjected to a thermal load, which decreases the accuracy of machining. The thermal load increases moreover when dry turning due to the missing heat convection through the cutting fluid. It is therefore necessary to investigate the effect of the reinforcement phase and the cutting condition used on the thermal load of the workpiece in dry turning. Therefore, composites with different reinforcement phases and the non-reinforced aluminum matrix were used as the workpiece materials. The reinforcement differs regarding the volume percent and the average size of the silicon carbide particulate reinforcements. The results revealed that the thermal load and the thermal expansion of the workpiece are significantly affected by the cutting condition used and the reinforcement phase. High cutting speeds and feeds and moderate depths of cut need to be used in order to decrease the thermal load of the workpiece. The Al-MMC workpieces are subjected to greater thermal loads than the workpieces of the non-reinforced alloy. However, better machining accuracies were achieved in dry turning the Al-MMCs. 相似文献
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为了研究干式切削齿轮加工过程碳排放特性,对齿轮加工过程的物料、能源消耗、废物处理及碳排放特性进行了分析,提出了齿轮加工过程碳排放边界条件,建立了齿轮加工过程碳排放计算模型;根据某制造企业提供的数据,将同批次齿轮的绿色干式切削和湿式切削加工过程的碳排放量进行计算与对比分析,结果显示,与湿式切削相比,干式切削齿轮加工过程碳排放总量约少55.69%,废弃物处理碳排放量少15.57%,表明面向绿色制造的干式齿轮加工的能源消耗、成本费用较低且环保,高速干式齿轮加工技术将成为未来齿轮制造业发展的主要趋势。 相似文献
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在干切削中,刀具遇到的突出问题是严重的摩擦和高温,只要合理地选择切削用量,减小切削热和摩擦对加工过程的影响,可以减轻干切削的不利条件,有效提高干切削刀具的耐用度,使干切削像湿切削一样在生产中顺利进行。通过试验的方法来证明干切削完全可以取得良好的加工效果。 相似文献
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高速干切滚齿工艺消除了切削油/液的使用,是一种绿色高效的齿轮制造工艺。切削热伴随着高速干切滚齿工艺全过程且区别于传统湿式滚切工艺,是造成干切滚刀磨损和机床热变形的重要因素,直接影响制造成本和加工精度。根据干切滚刀周期性断续传热特性,综合考虑切削热在切屑、工件、干切滚刀、冷却介质以及滚齿机床加工空间的传递规律,提出将高速干切滚齿工艺系统切削热的发生与传递全过程划分为三个阶段的研究思想,从关系模型和热传递方程两个层面建立了高速干切滚齿工艺系统切削热全过程传热模型,包括切削接触界面热传递、切削区域热传递和机床加工空间热传递三个阶段的模型,然后基于工艺仿真试验对所建模型进行了应用研究,揭示了高速干切滚齿工艺系统的切削热在工件、干切滚刀、切屑中的动态变化规律,最后通过试验验证了模型的有效性。 相似文献
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Fujian Sun Shengguan Qu Yuxiang Pan Xiaoqiang Li Chao Yang 《The International Journal of Advanced Manufacturing Technology》2014,73(5-8):613-622
In this paper, dry machining experiment of Ti-6Al-4 V was carried out to investigate the machining performance of a grooved tool in terms of its wear mechanisms and the effects of cutting parameters (cutting speed, feed rate, and cutting depth) on tool life and surface roughness of the machined workpiece. The results showed that chip-groove configuration substantially improved the machining performance of cutting tool. The main wear mechanisms of the grooved tool were adhesive wear, stripping wear, crater wear, and dissolution-diffusion wear. The resistance to chipping was enhanced due to the decrease of contact pressure of tool-chip interface. And the resistance to plastic deformation of tool nose was weakened at the cutting speed of more than 60 m/min. The appropriate cutting speed and feed rate were less than 70 m/min and 0.10 mm/r, respectively. With cutting speed increasing, the surface roughness of machined workpiece decreased. A high feed rate helped the formation of higher surface roughness except 0.21 mm/r. When cutting depth increased, tool nose curvature and phase transformation of workpiece material had great impact on surface roughness. 相似文献
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Zhang Fang-yuan Duan Chun-zheng Xu Xin-xin Wang Min-jie 《The International Journal of Advanced Manufacturing Technology》2018,98(1-4):77-84
White layer formed on machined surface during dry and hard high speed machining has great influence on workpiece performance. Studying machined surface white layer is significant to improve the machinability and surface quality of workpiece. Experiments of dry and hard high speed machining of GCr15 bearing steel and 40CrNiMoA alloy steel were carried out with PCBN inserts, the phase composition and the thickness of white layer were studied experimentally; the formation mechanism of the white layer were studied; effects of cutting parameters, carbon content of substrate material on white layer thickness were analyzed; effects of cutting speed on retained austenite content in machined surface were also summarized. Results show that the microstructure of white layer consists of cryptocrystalline martensite, retained austenite and carbide; the white layer is formed by martensitic transformation; the white layer thickness and the retained austenite content of machined surface increase firstly and then decrease with cutting speed; the white layer thickness increases with flank wear and carbon content. 相似文献