共查询到19条相似文献,搜索用时 187 毫秒
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论述了基于LOM原型电孤喷涂快速模具制造的基本原理及流程,并详细地介绍了LOM原型制造中的电弧喷涂金属丝的选择方法. 相似文献
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对链轮模具型腔电加工电极的电铸工艺进行了实践和探索,对芯模的制造、电铸操作等关键步骤进行了重点阐述。实践表明:电铸工艺是制造电火花加工用电极的一个有效方法。 相似文献
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概括介绍了快速原型制造(RPM)技术的特点及其发展现状,重点介绍了基于RPM的直接快速制模法以及RPM与电铸、金属喷涂、浇注、精密铸造和成型电极加工等特种加工方法组合的间接快速制模法,概述了快速模具制造技术的研究和发展概况。 相似文献
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本文叙述了用快速成形技术制造玻璃模具电火花加工电极.对客户提供的玻璃器皿样品尺寸进行三坐标测量,并将样品的尺寸放大1 mm以补偿样品生产时的收缩.利用快速成形技术对样品进行三雏造型,并制得样品的树脂原型.利用熔模铸造技术和树脂原型来制作模具电火花加工的电极.用这种工艺可以快速得到铜电极,实现玻璃模具的快速加工. 相似文献
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对电弧喷涂制模的工艺参数优化和喷涂丝材选择进行了试验研究,研究结果证明Zn—Al伪合金是具有优良综合性能的电弧喷涂材料,实例证明了基于FDM和LOM原型的电弧喷涂制模方法,是适合于新产品开发试制的快速经济制模技术。 相似文献
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H. -D. Steffens K. Nassenstein S. Keller G. Barbezat 《Journal of Thermal Spray Technology》1994,3(4):398-403
Electric arc spraying has been successfully used for many industrial applications for more than 30 years. High-velocity oxygen
fuel (HVOF) spraying is another well-established technology. Coatings produced by the HVOF process, especially carbide-containing
coatings, exhibit excellent quality in terms of density and hardness. One approach to obtaining both high deposition rates
and dense coatings is to combine electric arc spraying and HVOF spraying in a technique known as the “Sonarc” process. This
process al-lows many feed combinations through the simultaneous use of wire and powder. This paper presents the development
of a prototype. Examples of composite materials and structures, their properties, and potential applications are given. 相似文献
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化学镀镍内应力的研究 总被引:3,自引:0,他引:3
用于非金属电镀、电铸、化学镀、化学铸的现行许多化学镀镍工艺,总是在零件尖端部位发生崩裂,在镜面光洁的地方易起泡,这种难题至今未得到很好解决,这大大限制了化学镀镍的应用.针对这种情况,采用正交实验方法开发出一个低温、低内应力化学镀镍工艺,初步探讨了沉积层内应力与各工艺参数之间的关系,以及作为添加剂的糖精在化学沉积层中的作用机理,并对内应力和结合力的关系作了简介.实践证明了该工艺在短时间内能于多种复杂形状或镜面光亮的非金属表面上获得完整的化学镍沉积层. 相似文献
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C.C. Kao Albert J. Shih 《International Journal of Machine Tools and Manufacture》2006,46(15):1996-2008
Monitoring the gap voltage and current in micro-hole electrical discharge machining (EDM) using high-speed data acquisition with 0.5 ns sampling period is conducted. The spark and arc pulses at three stages, namely electrode dressing, drilling, and penetration, of the micro-hole EDM are recorded. The EDM process parameters are setup to use negative polarity to blunt the electrode tip and positive polarity for micro-hole drilling and penetration. A new phenomenon of pre-discharging current is discovered. In the first 20–30 ns of spark and arc pulses, the current starts to rise while the voltage remains the same. Effects of EDM process parameters, including the open voltage, electrode diameter, and polarity, on the rate of spark and arc pulses and electrode feed rate are investigated. A model based on the RLC circuit is developed to study the ringing effect at the end of a discharge. The intrinsic parasitic capacitance and resistance of a RLC circuit are calculated from the decaying voltage signal and compared under two sets of experiments with varying wire electrode diameter and gap voltage to validate the ringing model. The calculation and experimental results validate the proposed RLC model for ringing phenomenon. The model shows the electrode diameter has negligible effect on ringing and high open voltage increases the parasitic resistance and damping in ringing. The monitoring technique and ringing model developed in this research can assist in the selection and optimization of micro-hole EDM process parameters. 相似文献
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碳纤维铁网催化法化学镀镍 总被引:2,自引:2,他引:0
目的采用铁网催化的方法在碳纤维表面化学镀镍,取代传统的钯活化法。方法经去胶、粗化、分散前处理工艺后,采用铁网包覆对碳纤维化学镀镍进行催化反应,通过称重法、扫描电镜(SEM)研究催化时间、碳纤维分散状况以及粗化时间对镀层的影响,并通过能谱(EDS)对铁网催化法和钯活化法制备的镀层进行成分分析。结果铁网催化在10 min内时镀层存在缺陷,催化20 min镀层以颗粒状泡沫镍存在,超声分散优于分散剂CMC的分散效果。获得铁网催化法最佳工艺为:丙酮浸泡4 h去胶,80℃粗化处理15 min,超声分散,铁网包覆催化20 min诱导起镀,化学镀20 min。制备的镀层均匀、致密,从镀层各组分含量分析,并不差于钯活化法制备的镍镀层。结论铁网催化法可以在碳纤维上获得质量良好的镍-磷镀层。 相似文献
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采用无需常规敏化活化的预处理常温超声波化学镀方法制备Ni包覆WC复合粉体,以其作为增强相的粉芯丝材通过高速电弧喷涂技术制备FeMnCrAl/Ni包覆WC涂层。采用光学显微分析(OM)、场发射扫描电镜分析(FE-SEM)、能谱分析(EDS)以及涂层性能测试方法,研究Ni包覆WC复合粉体对涂层组织结构及性能的影响。结果表明:Ni包覆WC复合粉体能改善涂层中各相之间的结合状态,减少涂层中氧化物和孔隙率,提高涂层与基体的结合强度和涂层的内聚强度,改善了涂层抗冲蚀磨损性能。 相似文献
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Norliana Mohd Abbas Darius G. Solomon Md. Fuad Bahari 《International Journal of Machine Tools and Manufacture》2007,47(7-8):1214-1228
Electrical discharge machining (EDM) is one of the earliest non-traditional machining processes. EDM process is based on thermoelectric energy between the work piece and an electrode. A pulse discharge occurs in a small gap between the work piece and the electrode and removes the unwanted material from the parent metal through melting and vaporising. The electrode and the work piece must have electrical conductivity in order to generate the spark. There are various types of products which can be produced using EDM such as dies and moulds. Parts of aerospace, automotive industry and surgical components can be finished by EDM. This paper reviews the research trends in EDM on ultrasonic vibration, dry EDM machining, EDM with powder additives, EDM in water and modeling technique in predicting EDM performances. 相似文献
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FeCrBSiNb粉芯丝材电弧喷涂的弧区动态行为 总被引:1,自引:0,他引:1
电弧喷涂粉芯丝材是由金属外皮包覆金属或非金属的复合粉末组成,喷涂过程中在弧区发生冶金反应并雾化成熔滴,大量熔滴沉积在基体表面最终形成涂层。粉芯丝材的电弧喷涂是一个高度动态的传热传质过程,采用高速摄像技术研究了喷涂过程中两根粉芯丝材交汇处的电弧、丝材熔化与熔滴形成等行为。另外,通过高速摄像试验分析了喷涂电流和电压对电弧形态及丝材熔化的影响规律。结果表明:喷涂时间歇出现燃弧、熄弧、再燃弧的循环变化;不同于实心丝材,粉芯丝材在阴阳极上的电弧都发散,这有利于丝材外皮和粉芯间的冶金反应;阴极丝材主要表现为抽吸作用下以细小熔滴或片状挤出物等形式形成熔滴,阳极丝材主要以片状液带的形式脱离并雾化成小熔滴。 相似文献