共查询到18条相似文献,搜索用时 78 毫秒
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聚晶金刚石复合片的电火花线切割机理与形貌 总被引:6,自引:0,他引:6
开展了聚晶金刚石复合片(PDC)的电火花线切割实验,提出了PDC的电火花线切割模型。通过扫描电镜与拉曼光谱仪对切割试件进行显微观察与成分分析,发现聚晶金刚石层表面存在明显石墨化现象,而且聚晶金刚石层与硬质合金层之间的富钴界面层存在严重过量去除现象。按聚晶金刚石层、富钴界面层与硬质合金层三个部分剖析了PDC放电蚀除机理,并对PDC的电火花线切割热损伤进行了分析。研究表明,解决富钴界面层的过量去除问题是提高PDC电火花线切割加工质量的关键。 相似文献
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近几年来,北京电加工研究所在电火花应用技术方面进行了一系列有益的探索,特别是对聚晶金刚石复合片光整加工成套技术的研究,取得了突破性进展。聚晶金刚石复合片是由聚晶金刚石层及硬质合金衬片经高温高压烧结制成的。由于聚晶金刚石质地坚硬、耐磨,若采用金刚石砂轮进行常规机 相似文献
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聚晶金刚石复合片有高硬度和良好的韧性,是理想的刀具材料.采用金刚石砂轮对聚晶金刚石(PCD)复合片材料的聚晶金刚石层进行了磨削试验,研究了磨削工艺参数和砂轮特性对磨削力的影响. 相似文献
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徐载熊 《机械工人(冷加工)》1992,(9)
聚晶金刚石是一种复合材料,它是用微米级的人造金刚石作原料,与硬质合金衬底在1400℃以上的高温和6000MPa左右的高压条件下烧结而成的。聚晶金刚石层仅0.5~0.7mm,硬质合金衬底层也只有几毫米厚。 相似文献
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PCD刀具在非金属材料加工中的应用 总被引:3,自引:2,他引:1
1 引言 PCD刀具泛指用人造复合聚晶金刚石片(简称PCD)制造的切削刀具.人造复合聚晶金刚石片是将聚晶金刚石微粉通过高温高压烧结压制在硬质合金基体上形成的硬质合金-金刚石复合材料.用其制作的PCD刀具既具有金刚石的高硬度、高强度同时又具有硬质合金的韧性. 相似文献
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超硬材料刀具的性能及用途 总被引:17,自引:0,他引:17
介绍单晶金刚石刀具,聚晶金刚石刀具、金刚石膜刀具、聚晶立方氮化硼刀 具的性能及作用,并以其为代表,概述国内外超硬材料加工刀具的现状发展。 相似文献
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Abrasion resistance of nanostructured and conventional cemented carbides 总被引:10,自引:0,他引:10
The abrasion resistance of nanostructured WC-Co composites, synthesized by a novel spray conversion method, is determined and compared with that of conventional materials. Scratching by diamond indenter and abrasion by hard (diamond), soft (zirconia) and intermediate (SiC) abrasives was investigated. The size of the scratch formed by the diamond is simply related to the hardness of the composite. Plastic deformation, fracture and fragmentation of the WC grains increase with their size. Nanoscale composites show purely ductile scratch formation. Nanocomposites possess an abrasion resistance approximately double that of the most resistant conventional material: this is a higher gain than the increase in hardness which is at most 23%. This large gain is due to a specific grain size effect on abrasion resistance in the case of diamond and SiC abrasive and to a very rapid increase of abrasion resistance with hardness in the case of the softer (SiC and ZrO2) abrasives. The observation of the abraded surfaces of conventional composites reproduced the known mechanisms: plastic deformation and fracture of WC grains by hard abrasives; removal of binder phase and fall-out of WC by soft abrasives. Magnetic fields from the ferromagnetic Co prevent the observation of abrasion mechanisms in the very fine-structured nanocomposites. 相似文献
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聚晶金刚石的Nd:YAG激光切割与电火花线切割损伤分析 总被引:1,自引:0,他引:1
采用近红外Nd:YAG激光切割方法与电火花线切割方法进行了聚晶金刚石(polycrystalline diamond compacts,PDC)切割加工实验,并分别利用细砂纸打磨、金刚石微粉抛光以及王水腐蚀等表面处理方法对试件进行了表面处理,通过扫描电镜显微观察与拉曼光谱分析等方法对试件进行了显微观察与分析。经分析发现:尽管近红外Nd:YAG激光切割速度较快,然而因脉宽较大导致热损伤大,加工表面存在明显的残留层,而且金刚石与硬质合金层界面存在明显的裂纹;电火花线切割表面质量好于激光切割加工,但金刚石界面处存在材料过量去除现象,而且切割速度比近红外激光切割加工小得多。为获得较好的PDC切割质量与切割效率,需采用脉宽更短的Nd:YAG激光或紫外激光。 相似文献
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The wear and strength characteristics of the mounted diamond have been studied during the application of a new type of dressing for abrasive wheels. The diamond dresser is mounted on an elastic base in order to perform oscillations during dressing under the action of abrasive grain impacts. The experiments were aimed at determining the value of the diamond grain wear of the dressing tool, the number of the treated samples up to the forced substitution of the dressing tool, and the lifetime of the dressing tool at vibromechanical and common types of dressing. The tests have shown a significant increase in the resistance of the diamond dressing tool in the case when the vibromechanical method was used, in contrast to a common dressing by a mounted diamond wheel. 相似文献