共查询到20条相似文献,搜索用时 119 毫秒
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使用TiSiN和TiAlN涂层刀具在3种不同冷却润滑方式下,在高速加工中心上采用固定的切削工艺参数,对淬硬钢SKD11(HRC 62)进行切削试验,研究加工工件的表面粗糙度、切削力、刀具磨损及切屑形态的不同.结果 表明:TiSiN涂层铣刀相对于TiAlN涂层能更好地降低已加工面的表面粗糙度,减小切削力,降低刀具的磨损;在微量润滑(MQL)方式下,已加工面的表面粗糙度值低于干切削和冷风切削条件;在减小切削力、降低刀具磨损、改善切屑形态方面,冷风切削的效果优于干切削,MQL润滑方式增大了刀具切削力. 相似文献
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王彩英 《机电产品开发与创新》2013,26(5):130-132
45淬硬钢的主要性能是硬度高、强度高、脆性大、导热性差、切削加工性差,切削加工困难大。它在切削加工中有以下特点:切削力大、切削温度高,刀具易磨损;淬硬钢径向切削力较大;切削淬硬钢时切屑与前刀面接触长度短,因此切削力和切削温度集中在切削刃附近,易使刀具磨损和崩刃;易获得较高的表面质量。为了获得更高的加工精度和表面粗糙度,论文对45淬硬钢切削力进行了研究。 相似文献
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Ramesh Kuppuswamy Akinori Yui 《The International Journal of Advanced Manufacturing Technology》2017,90(1-4):11-20
The present study includes three parts—design and development of rotary liquid nitrogen applicator, investigation of machining performance under cryogenic application by using the developed applicator, and lastly comparison of the performances with dry and flood cutting. The surface milling of hardened EN 24 steel was performed at different speed-feed combinations corresponding to full factorial design plan (48 exp. runs). The effects of cutting speed, feed rate, and cutting conditions were investigated in respect of surface roughness, cutting force, and tool flank wear. The results of this study revealed the supremacy of cryogenic cooling in respect of all investigated quality characteristics. Lack of cooling and lubrication in dry cutting, and inadequate cooling and lubrication of flood cutting resulted in worse performance. On contrary, the double action cooling effect of cryogenic produces a superior performance, when passes through internal channel, firstly—due to an increased heat transfer rate caused by the primary and secondary flow within cutter, and secondly—because of the creation of a swirl flow at the outlet of the channel but within work surface. 相似文献
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Welber Vasconcelos Leadebal Jr. Adilson José De Oliveira Nicolau Apoena Castro 《Machining Science and Technology》2013,17(6):886-905
AbstractSustainability is a concept which is widely considered nowadays, including in factories where machining operations are present. The search for methods able to improve the performance of industrial processes without damaging the environment or the worker’s health has been the main goal of several investigations. In this context, cryogenic machining is a technique that has been studied as an alternative to the use of mineral oil-based cutting fluids, mainly in the machining of titanium and nickel alloys. Investigations on the cryogenic machining of hard tool steels are still scarce in the literature. This article presents results from a series of turning trials under dry and cryogenic conditions using a hardened AISI D6 tool steel bar (57 HRC) as the workpiece. For the cryogenic machining tests, liquid nitrogen was delivered to the flank face, rake face and on both faces of PCBN inserts. The main cutting parameters (cutting speed, feed rate, and depth of cut) were kept constant during the trials. Tool wear and chip morphology were the output variables studied. The results show that the liquid nitrogen was able to reduce the cutting tool wear, providing a tool lifetime around 50% longer compared with the dry process. Moreover, the frequency of chip segmentation was diminished under cryogenic conditions in comparison with the dry process. 相似文献
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针对钛合金难加工特点,将液氮作为冷却介质直接喷向切削区进行钛合金TC4低温车削加工,测量其切削力、表面粗糙度和刀具磨损,并与干切削在相同实验条件下对比,分析低温切削对钛合金的影响。实验结果表明:低温切削钛合金,主切削力有所增大,但进给方向力减小,刀具磨损状况与表面质量得到改善,断屑相对容易。 相似文献
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低温氮气射流对钛合金高速铣削加工性能的影响 总被引:7,自引:0,他引:7
在钛合金的高速切削过程中,切削区温度很高,加速了刀具的磨损,限制了切削速度的进一步提高。为降低切削区温度、防止刀具的氧化磨损,提出在低温氮气射流条件下进行钛合金的高速铣削加工。在干铣削、浇注切削液、常温氮气油雾、低温氮气射流和低温氮气射流结合微量润滑等冷却润滑条件下进行了钛合金的高速铣削对比试验。试验结果表明,低温氮气射流结合微量润滑能够最有效地降低铣削力,抑制刀具磨损。借助扫描电镜的检测手段,研究了不同冷却润滑条件下刀具的失效形式。指出在低温氮气射流条件下高速铣削钛合金时,只要热裂纹的形成与扩展未引起刀具的崩刃及刀面的剥落,进一步降低低温氮气的温度将提高刀具的使用寿命。 相似文献
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液氮冷却下大进给铣削TC4钛合金的试验研究 总被引:1,自引:0,他引:1
钛合金是现代飞行器的主要结构材料之一,是一种典型的难加工材料。针对切削加工钛合金时刀具磨损快、表面质量不易控制等难题,将TC4钛合金作为研究对象,以液氮作为冷却介质,进行了TC4钛合金的大进给铣削试验,测试了液氮冷却条件下大进给铣削TC4钛合金的铣削力、铣削温度以及刀具磨损等,并与乳化液和低温冷风条件下的测试结果进行了对比分析。结果表明:在以较大的切削速度和每齿进给量铣削TC4钛合金时,采用液氮冷却比使用乳化液能更有效地降低切削力和切削温度;比采用低温冷风冷却能更有效地延长刀具寿命。 相似文献
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Productivity in machining of 17-4 PH stainless steel is adversely affected by the premature failure of tool and poor surface finish as a consequence of high cutting temperatures. Conventional cutting fluids not only create environmental and health problems but also fail to overcome the high cutting temperatures during machining. Cryogenic cooling is an environmentally clean cooling technology for attractive management of machining zone temperatures. The present study investigates the effect of cryogenic liquid nitrogen (LN2 at ?196°C) on cutting temperatures, cutting forces (main cutting force, feed force), surface roughness, tool flank wear and chip morphology in turning of 17-4 PH stainless steel with AlTiN PVD-coated tungsten-coated carbide inserts and results were compared to wet machining. In overall, cryogenic machining reduces the cutting temperature, cutting forces, surface roughness and tool flank wear to a maximum of 73.4, 17.62, 44.29 and 55.55%, respectively. Improved chip breakability was found in cryogenic machining. 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