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Characterization of IN 625 recycled metal powder used for selective laser melting 选择性激光熔化用IN 625再生金属粉末的表征
IF 2.5 Q2 Engineering Pub Date : 2020-01-01 DOI: 10.1051/mfreview/2020002
M. Condruz, G. Matache, A. Paraschiv
Additive manufacturing of high-quality materials by Selective Laser Melting depends not only on establishing appropriate process parameters, but also on the characteristics of the metal powders used and their stability over time or after recycling. The aim of the research was to characterize the IN 625 powder used over multiple manufacturing cycles with a Lasertec 30 SLM machine. In order to achieve the research's goal, virgin and recirculated powder's physical and technological characteristics were investigated. A decrease in all D-values (D10, D50, D90) of the powder size distribution was observed after multiple recirculation cycles showing a decrease of the powder dimensional range over time. Both virgin and recirculated powders are composed of mainly spherical particles, but elongated particles and satellite particles were observed as well. The dimensional evolution analysis showed a deviation from the powder ideal roundness, deviation that is more pronounced over multiple recirculation cycles. It was experimentally determined that the powders present a good flowability based on the flow rate value obtained for both virgin and recirculated powders, confirmed also by the Hausner ratio and angle of repose.
通过选择性激光熔化增材制造高质量材料不仅取决于建立合适的工艺参数,还取决于所使用金属粉末的特性及其随时间或回收后的稳定性。该研究的目的是在Lasertec 30 SLM机器上对多个制造周期使用的IN 625粉末进行表征。为了达到研究目的,对初粉和再循环粉的物理特性和工艺特性进行了研究。在多次再循环后,观察到粉末粒度分布的所有d值(D10, D50, D90)均下降,显示粉末尺寸范围随时间的推移而减少。初粉和再循环粉主要由球形颗粒组成,但也观察到细长颗粒和卫星颗粒。尺寸演化分析表明,偏离了理想的粉末圆度,这种偏离在多次再循环中更为明显。实验结果表明,所制备的粉末具有良好的流动性,其流动速率为初磨和再循环粉末的流量值,豪斯纳比和休止角也证实了这一点。
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引用次数: 6
Extension of the forming limits of extrusion processes in sheet-bulk metal forming for production of minute functional elements 用于生产微小功能部件的薄板-大块金属成形中挤压成形极限的扩展
IF 2.5 Q2 Engineering Pub Date : 2020-01-01 DOI: 10.1051/mfreview/2020003
F. Pilz, J. Henneberg, M. Merklein
Increasing demands in modern production pose new challenges to established forming processes. One approach to meet these challenges is the combined use of established process classes such as sheet and bulk forming. This innovative process class, also called sheet-bulk metal forming (SBMF), facilitates the forming of minute functional elements such as lock toothing and gear toothing on sheet-metal bodies. High tool loads and a complex material flow that is hard to control are characteristic of SBMF. Due to these challenging process conditions, the forming of functional elements is often insufficient and necessitates rework. This negatively affects economic efficiency. In order to make use of SBMF in industrial contexts, it is necessary to develop measures for improving the forming of functional elements and thereby push existing forming boundaries. This paper describes the design and numerical replication of both a forward and a lateral extrusion process so as to create involute gearing in combination with carrier teeth. In a combined numerical-experimental approach, measures for extending the die filling in sheet-metal extrusion processes are identified and investigated. Here, the focus is on approaches such as process parameters, component design and locally adjusted tribological conditions; so-called ‘tailored surfaces’. Based on the findings, fundamental mechanisms of action are identified, and measures are assessed with regard to their potential for application. The examined approaches show their potential for improving the forming of functional elements and, consequently, the improvement of geometrical accuracies in functional areas of the workpieces.
现代生产日益增长的需求对现有的成形工艺提出了新的挑战。应对这些挑战的一种方法是结合使用已建立的工艺类,如板材和批量成型。这种创新的工艺类,也称为板-散装金属成形(SBMF),有利于形成微小的功能元件,如锁齿和齿轮齿在板-金属体。高刀具负荷和难以控制的复杂物料流是SBMF的特点。由于这些具有挑战性的工艺条件,功能元件的形成往往不足,需要返工。这对经济效率产生了负面影响。为了在工业背景下利用SBMF,有必要制定改善功能要素形成的措施,从而推动现有的形成边界。本文描述了正挤压和侧向挤压过程的设计和数值模拟,以形成与载齿结合的渐开线齿轮传动。采用数值与实验相结合的方法,确定并研究了板材挤压过程中延长模具填充量的措施。在这里,重点是方法,如工艺参数,部件设计和局部调整的摩擦学条件;所谓的“定制表面”。根据调查结果,确定了基本的行动机制,并就其应用潜力评估了各项措施。所研究的方法显示了它们改善功能元件成形的潜力,从而提高了工件功能区域的几何精度。
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引用次数: 5
Development of palladium nanoparticles deposition on a copper substrate using a molecular dynamic (MD) simulation: a cold gas dynamic spray process 用分子动力学(MD)模拟在铜衬底上沉积钯纳米粒子:冷气体动态喷涂过程
IF 2.5 Q2 Engineering Pub Date : 2020-01-01 DOI: 10.1051/mfreview/2020028
S. Oyinbo, T. Jen, S. A. Aasa, O. Abegunde, Yudan Zhu
The objective of this study is to create an ultra-thin palladium foil with a molecular dynamic (MD) simulation technique on a copper substrate surface. The layer formed onto the surface consists of a singular 3D palladium (Pd) nanoparticle structure which, by the cold gas dynamic spray (CGDS) technique, is especially incorporated into the low-cost copper substrate. Pd and Cu have been chosen for their possible hydrogen separation technology applications. The nanoparticles were deposited to the substrate surface with an initial velocity ranging from 500 to 1500 m/s. The particle radius was 1 to 4 nm and an angle of impact of 90° at room temperature of 300 K, in order to evaluate changes in the conduct of deformation caused by effects of size. The deformation mechanisms study revealed that the particle and substrate interface is subject to the interfacial jet formation and adiabatic softening resulting in a uniform layering. However, shear instabilities at high impact speeds were confirmed by the evolution of von Mises shear strain, temperature evolution and plastic strain. The results of this study can be used to further our existing knowledge in the complex spraying processes of cold gas dynamic spray technology.
本研究的目的是利用分子动力学(MD)模拟技术在铜衬底表面制备超薄钯箔。在表面形成的层由单一的三维钯(Pd)纳米颗粒结构组成,通过冷气体动态喷涂(CGDS)技术,特别将其纳入低成本的铜基板中。选择钯和铜是由于它们可能的氢分离技术应用。纳米颗粒以500 ~ 1500m /s的初始速度沉积到衬底表面。在室温300 K下,颗粒半径为1 ~ 4 nm,冲击角为90°,以评价尺寸对变形行为的影响。变形机理研究表明,颗粒与基体界面受界面射流形成和绝热软化的影响,形成均匀的层状。然而,von Mises剪切应变、温度演化和塑性应变的演化证实了高冲击速度下的剪切不稳定性。本研究的结果可用于进一步深化我们在复杂喷涂过程中的冷气动态喷涂技术的现有知识。
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引用次数: 6
Measures for controlling the material flow when extruding sheet-bulk metal forming parts from coil 从卷材中挤出板材-大块金属成形件时控制物料流动的措施
IF 2.5 Q2 Engineering Pub Date : 2020-01-01 DOI: 10.1051/mfreview/2020033
J. Henneberg, M. Merklein
The increasing demand for lightweight design requires functional integration. This poses challenges to conventional manufacturing processes due to the rising geometrical complexity of components. The application of bulk forming operations to sheet metal, named sheet-bulk metal forming (SBMF), is one approach to overcome these challenges. Currently, mainly pre-cut blanks are applied in research of SBMF. Production from coil, in contrast, would combine the advantages of SBMF with the advantages of manufacturing from a coil regarding high output quantity. To research SBMF from coil, a lateral and a backward extrusion process are set up. In addition to a reduced geometrical accuracy of the parts, which is known from SBMF of pre-cut blanks, an anisotropic material flow is identified as a coil-specific challenge. The aim of this research is to investigate measures that extend the forming limits by means of a material flow control. For this purpose, a combined numerical-experimental approach is applied in order to analyze and evaluate an adaption of the width of the coil, the feed width, and the local friction as measures for material flow control. Particularly local adaptation of friction by means of modified tool surfaces reduces the anisotropic material flow and improves the geometrical accuracy of the parts.
对轻量化设计日益增长的需求要求功能集成。由于部件几何复杂性的增加,这对传统制造工艺提出了挑战。将大体积成形技术应用于金属薄板,称为薄板-大体积金属成形(SBMF),是克服这些挑战的一种方法。目前,预切坯料主要应用于SBMF的研究。相比之下,线圈生产将结合SBMF的优势和线圈制造在高产量方面的优势。为了研究卷材的SBMF,建立了横向挤压和反向挤压工艺。除了从预切毛坯的SBMF可知的零件几何精度降低之外,各向异性材料流被认为是线圈特有的挑战。本研究的目的是研究通过材料流控制来延长成形极限的措施。为此,采用了数值-实验相结合的方法来分析和评估线圈宽度、进料宽度和局部摩擦作为物料流动控制措施的适应性。特别是通过修改刀具表面来局部适应摩擦,减少了材料流动的各向异性,提高了零件的几何精度。
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引用次数: 0
Nanoindentation studies and analysis of the mechanical properties of Ti-Nb2O5 based composites Ti-Nb2O5基复合材料的纳米压痕研究与力学性能分析
IF 2.5 Q2 Engineering Pub Date : 2020-01-01 DOI: 10.1051/mfreview/2020017
K. Alaneme, Ayoyemi Adebanji Fatokun, S. R. Oke, P. Olubambi
In this study, nanoindentation tests were used to evaluate the mechanical properties of spark plasma sintered Ti based composites containing 5, 10 and 15 wt.% Nb2O5, targeted for potential use as biomedical material. Nanoindentation tests were performed on the samples using indenter loads of 20 and 100 mN, while the microstructures were characterized using scanning electron microscopy. It was noted that with increasing Nb2O5 wt.%, there is transition from the lamellar structure of pure Ti to fully bimodal structures for the Ti-10 wt.% Nb2O5 and Ti-15 wt.% Nb2O5 composites. The hardness (6.0–40.67 GPa (20 mN) and 2.4–12.03 GPa (100 mN)) and reduced elastic modulus (115–266.91 GPa (20 mN) and (28.05–96.873 GPa (100 mN)) of the composites increases with increase in the Nb2O5 content, attributed to contributions of load transfer from the Ti matrix to the relatively harder Nb2O5 particles, particle and dispersion strengthening mechanisms. The elastic recovery index also improved with increase in Nb2O5 content, while the inverse was noted with respect to plasticity index. The elastic strain to failure and yield pressure both improved with increase in Nb2O5 content, which suggests that the antiwear properties and resistance to impact loading equally improves with Nb2O5 addition.
在这项研究中,采用纳米压痕测试来评估含有5、10和15 wt的火花等离子烧结Ti基复合材料的力学性能。% Nb2O5,目标是作为生物医学材料的潜在用途。采用20和100 mN的压头载荷对样品进行了纳米压痕测试,并用扫描电镜对样品的微观结构进行了表征。随着Nb2O5重量的增加。%时,Ti- 10wt从纯Ti的片层结构转变为完全双峰结构。% Nb2O5和Ti-15 wt。% Nb2O5复合材料。随着Nb2O5含量的增加,复合材料的硬度(6.0 ~ 40.67 GPa (20 mN)和2.4 ~ 12.03 GPa (100 mN))和弹性模量(115 ~ 266.91 GPa (20 mN)和降低弹性模量(28.05 ~ 96.873 GPa (100 mN))均随Nb2O5含量的增加而增加,这主要是由于Ti基体的载荷转移作用于相对较硬的Nb2O5颗粒、颗粒和弥散强化机制。随着Nb2O5含量的增加,材料的弹性恢复指数也有所提高,而塑性指数则相反。随着Nb2O5含量的增加,材料的失效弹性应变和屈服压力均有所提高,表明Nb2O5的加入同样提高了材料的抗磨性能和抗冲击载荷能力。
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引用次数: 4
Weldability of S700MC steel welded with the hybrid plasma + MAG method 等离子体+ MAG复合焊法焊接S700MC钢的可焊性
IF 2.5 Q2 Engineering Pub Date : 2020-01-01 DOI: 10.1051/mfreview/2020001
Beata Skowrońska, T. Chmielewski, D. Golański, J. Szulc
The paper describes the microstructure of welded joints produced by the plasma+MAG (Metal Active Gas) method of S700MC high yield strength steel (700 MPa). Welded joints of thermomechanical steel have been made with different values of heat input. The results of metallographic research of welded joints, microstructure of the weld and heat affected zone, hardness distribution and impact toughness are presented. The heat affected zone consists of two sub-zones with different grain size and lowered hardness. The tensile test show that strength of welded joints was slightly reduced and the bending test revealed no crack formation in the weld. The impact toughness of measured welded samples with V-notch in HAZ (heat affected zone) reached high values that are higher comparing to samples with notch placed in the weld area. The investigation results show that the use of plasma concentrated heat source together with MAG welding arc does not significantly change the structure and deteriorate properties of welded S700MC thermomechanically treated high strength steel. The hybrid plasma+MAG welding method has a potential to become a beneficial alternative to other welding processes due to its high efficiency, reduced amount of weld metal content or limited requirements for a preparation of edges of welded joints.
介绍了S700MC高屈服强度钢(700mpa)等离子体+MAG法焊接接头的显微组织。用不同的热输入值制作了热机械钢的焊接接头。介绍了焊接接头金相组织、焊缝及热影响区的显微组织、硬度分布和冲击韧性的研究结果。热影响区由两个不同晶粒尺寸和硬度降低的子区组成。拉伸试验表明焊接接头的强度略有降低,弯曲试验表明焊缝未形成裂纹。在热影响区放置v形缺口的焊接试样的冲击韧性达到了很高的值,比在焊缝区放置缺口的试样的冲击韧性更高。研究结果表明,等离子体集中热源与MAG焊接电弧对S700MC高强度钢焊接后的组织和性能没有明显的改变。等离子体+MAG混合焊接方法由于其效率高、焊缝金属含量少或对焊接接头边缘制备要求有限,有可能成为其他焊接工艺的有益替代方法。
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引用次数: 29
Innovative hydraulic lime-based finishes with unconventional aggregates and TiO2 for the improvement of indoor air quality 创新的液压石灰基饰面采用非常规的骨料和二氧化钛,以改善室内空气质量
IF 2.5 Q2 Engineering Pub Date : 2020-01-01 DOI: 10.1051/mfreview/2020010
C. Giosué, A. Mobili, B. Citterio, F. Biavasco, M. Ruello, F. Tittarelli
This paper reports a study on 8 unconventional hydraulic lime-based mortars able to improve indoor air quality by acting as passive systems. Mortars have been prepared with commercial sand or highly adsorbent materials as aggregates with/without TiO2 as photocatalytic agent, to test also the decomposition of airborne pollutants. Mechanical properties, hygrometric behavior, inhibition of growth of molds and depollution properties have been tested. Despite using porous materials (zeolite and activated carbon), in mortars with unconventional aggregates, compressive strength is higher than in sand-based ones, with a more than double higher water vapor permeability. Zeolite-based mortars have the highest moisture buffering capacity followed by silica gel- and activated carbon-based mortars (1.5–2 times higher than reference, respectively, because of the high porosity of unconventional aggregates). Sand-based mortars show optimum inhibitory capacity against fungal growth. Concerning unconventional aggregates, silica gel mortars have good inhibitory capacity, whereas zeolite and activated carbon give to mortars an optimum substrate for molds. Mortars with unconventional aggregates as silica gel remove more than 80% of tracer pollutant after 2 h of test, whereas zeolite-based mortars remove the 65% of it after 120 min. TiO2 enhances depollution properties as photocatalytic oxidation agent when the mortar is close to saturation.
本文报道了8种非常规液压石灰基砂浆作为被动系统改善室内空气质量的研究。用商品砂或高吸附性材料作为骨料制备砂浆,用/不加TiO2作为光催化剂,同时测试对空气中污染物的分解。测试了其机械性能、吸湿性能、抑制霉菌生长和去污性能。尽管使用多孔材料(沸石和活性炭),但非常规骨料砂浆的抗压强度高于砂基砂浆,透气性高出一倍以上。沸石基砂浆具有最高的水分缓冲能力,其次是硅胶基砂浆和活性炭基砂浆(分别比参考材料高1.5-2倍,因为非常规骨料的高孔隙率)。砂基砂浆对真菌生长的抑制能力最佳。对于非常规骨料,硅胶砂浆具有良好的抑制能力,而沸石和活性炭则是砂浆对霉菌的最佳基质。以非常规骨料为硅胶的砂浆在测试2小时后可去除80%以上的示踪污染物,而沸石基砂浆在测试120分钟后可去除65%的示踪污染物。当砂浆接近饱和时,TiO2作为光催化氧化剂增强了砂浆的去污性能。
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引用次数: 5
Parametric optimization while turning Ti-6Al-4V alloy in Mist-MQCL (Green environment) using the DEAR method 采用DEAR方法对Ti-6Al-4V合金在Mist-MQCL (Green environment)环境下的车削参数进行优化
IF 2.5 Q2 Engineering Pub Date : 2020-01-01 DOI: 10.1051/mfreview/2020034
V. Lakshmi, K. Subbaiah, Arun Vikram Kothapalli, K. Suresh
Sustainability in any production emphasizes green-manufacturing techniques, improvement in quality with energy-efficient techniques, and environment-friendly processes. Titanium machining productivity is greatly influenced by speed, as high cutting velocity raises the temperatures in the shear zone and heat, owing to its low thermal conductivity. Hence in this work, an attempt is made to increase productivity by exploring the efficacy at transition speed for titanium alloy machining. Water-soluble lubricant is mist-sprayed as aerosols at a near-zero temperature in minor quantity, to minimize the temperatures generated during the cutting process at increased speed. Besides, an optimal decision variable vector optimizes multi-goals of machining Titanium grade 5 alloys under Minimum quantity cooling lubrication explored in this study in transitional speed zones. The response goals are the optimization of “vibration, surface quality, tool wear rate, and Material removal rate.” Multi goal optimization achieved by hybrid Taguchi coupled with Data Envelopment Analysis based Ranking (DEAR). The tool wear is very rapid at velocities of 200 mm/min. DEAR technique uses computed Multi performance rank index (MPRI) to predict the best data set at: (velocity, feed, doc) at (120 mm/min, 0.2 mm/rev, 1.0 mm). In this setting, the responses are compared in dry, flood, and MQL environment. It is observed a 30%, 60%, 40% improvement in surface finish, tool life, and vibrations compared to a dry environment and 13% and 3% of roughness and tool wear rate compared to a flood environment. Thus MQCL can be adopted for Ti6Al4V at transitional speeds.
任何生产的可持续性都强调绿色制造技术,用节能技术提高质量,以及环境友好的过程。钛的加工效率很大程度上受速度的影响,因为高切削速度提高了剪切区的温度和热量,这是由于钛的低导热性。因此,本工作试图通过探索钛合金加工过渡速度的有效性来提高生产率。少量的水溶性润滑剂以气溶胶的形式在接近零的温度下喷雾,以尽量减少在增加速度的切割过程中产生的温度。此外,本文还提出了一个最优决策变量向量,对过渡速度区5级钛合金在最少量冷却润滑条件下加工的多目标进行了优化。响应目标是“振动、表面质量、刀具磨损率和材料去除率”的优化。混合田口法结合基于数据包络分析的排序法实现多目标优化。在200毫米/分钟的速度下,刀具磨损非常快。DEAR技术使用计算的多重性能排名指数(MPRI)来预测(速度,进料,文件)在(120 mm/min, 0.2 mm/rev, 1.0 mm)下的最佳数据集。在此设置中,比较了干旱、洪水和MQL环境下的响应。与干燥环境相比,表面光洁度、工具寿命和振动提高了30%、60%和40%,与水浸环境相比,粗糙度和工具磨损率分别提高了13%和3%。因此,MQCL可以在过渡速度下用于Ti6Al4V。
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引用次数: 14
Review on globularization of titanium alloy with lamellar colony 钛合金片层集落球化研究进展
IF 2.5 Q2 Engineering Pub Date : 2020-01-01 DOI: 10.1051/mfreview/2020015
Jian Zhang, Hong-wei Li, M. Zhan
The globularization of titanium alloy with lamellar colony during hot working is an important way to obtain fine and homogeneous microstructure which has excellent mechanical properties. Because of its great technological importance, globularization has captured wide attention and much research. This paper conducts a systematic study on state of art on globularization of titanium alloy, which mainly includes globularization mechanism, prediction model and the effects of hot-working parameters and microstructure parameters. Firstly, the shortcomings of the well-known globularization mechanisms (dynamic recrystallization, boundary splitting, shearing mechanism and termination migration) were summarized. Moreover, the comparison and analysis of prediction models were accomplished through tabular form. In addition, the effects of hot-working parameters (strain, strain rate, temperature) and microstructure parameters (alpha/beta interface, geometry necessary dislocation and high temperature parent beta phase) were systematically summarized and analyzed. Meanwhile, this study also explores those difficulties and challenges faced by precise control on globularization. Finally, an outlook and development tendency of globularization of titanium alloy are also provided, which includes microstructure evolution of three-dimensional lamellar alpha, the relationship between lamellar colony and mechanical properties and the effect of severe plastic deformation on globularization.
钛合金在热加工过程中发生片层集落的球化是获得细小均匀的组织并具有优异力学性能的重要途径。由于全球化在技术上的重要性,它引起了广泛的关注和研究。本文对钛合金的球化研究现状进行了系统的研究,主要包括球化机理、预测模型以及热加工参数和显微组织参数的影响。首先,总结了常用的全球化机制(动态再结晶、边界分裂、剪切机制和终止迁移)的不足;并通过表格形式对预测模型进行了比较分析。此外,系统地总结和分析了热加工参数(应变、应变速率、温度)和微观结构参数(α / β界面、几何必要位错和高温母β相)的影响。同时,本研究也探讨了精准控制全球化所面临的困难和挑战。最后,对钛合金球化的发展趋势进行了展望,包括三维片层α的微观组织演变、片层集落与力学性能的关系以及剧烈塑性变形对球化的影响。
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引用次数: 10
Study of cutting force and tool wear during turning of aluminium with WC, PCD and HFCVD coated MCD tools 用WC、PCD和HFCVD涂层MCD刀具车削铝时切削力和刀具磨损的研究
IF 2.5 Q2 Engineering Pub Date : 2020-01-01 DOI: 10.1051/mfreview/2020026
S. K. Pattnaik, M. Behera, S. Padhi, P. Dash, S. K. Sarangi
Enormous developmental work has been made in synthesis of metastable diamond by hot filament chemical vapor deposition (HFCVD) method. In this paper, micro-crystalline diamond (MCD) was deposited on WC–6 wt.% Co cutting tool inserts by HFCVD technique. The MCD coated tool was characterized by the scanning electron microscope (SEM), X-ray diffraction (XRD) and micro Raman spectroscopy (μ-RS). A comparison was made among the MCD tool, uncoated tungsten carbide (WC) tool and polycrystalline diamond (PCD) tool during the dry turning of rolled aluminum. The various major tests were conducted such as surface roughness, cutting force and tool wear, which were taken into consideration to establish a proper comparison among the advanced cutting tools. Surface roughness was measured during machining by Talysurf. The tool wear was studied by SEM after machining. The cutting forces were measured by Kistler 3D-dynamometer during the machining process. The test results indicate that, the CVD coated MCD tool and PCD tool produced almost similar results. But, the price of PCD tools are five times costlier than MCD tools. So, MCD tool would be a better alternative for machining of aluminium.
热丝化学气相沉积(HFCVD)法合成亚稳金刚石的研究取得了巨大的进展。本文将微晶金刚石(MCD)沉积在WC-6 wt上。% Co切削刀具刀片采用HFCVD技术。采用扫描电镜(SEM)、x射线衍射(XRD)和微拉曼光谱(μ-RS)对MCD涂层工具进行了表征。对MCD刀具、未涂覆碳化钨刀具和聚晶金刚石刀具干式车削轧制铝进行了比较。进行了表面粗糙度、切削力和刀具磨损等主要测试,以建立先进刀具之间的适当比较。用Talysurf测量了加工过程中的表面粗糙度。通过扫描电镜研究了加工后刀具的磨损情况。利用Kistler三维测功仪测量加工过程中的切削力。测试结果表明,CVD涂层MCD工具与PCD工具的测试结果基本一致。但是,PCD工具的价格是MCD工具的5倍。因此,MCD刀具将是铝加工的更好选择。
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引用次数: 4
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