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Analysis of the cutting fluid influence on the deep grinding process with a CBN grinding wheel
Fusse, Ronaldo Yoshinobu;Fran?a, Thiago Valle;Catai, Rodrigo Eduardo;Silva, Leonardo Roberto da;Aguiar, Paulo Roberto de;Bianchi, Eduardo Carlos;
Materials Research , 2004, DOI: 10.1590/S1516-14392004000300013
Abstract: the application of cutting fluid in a deep grinding process is becoming more and more important, mainly where the cutting fluids are used as an "external" agent to the grinding conditions. the role of the fluid in grinding operations is in refrigeration of the workpiece, removal of the shavings, lubrication of the grinding zone, and refrigeration and cleaning of the wheel. the efficiency of a cutting fluid will depend mainly of the type of fluid that will be used. in this work, the influences of the type of cutting fluid used in a deep grinding process of the steel vc131 using cbn grinding wheel are analyzed. three different types of cutting fluids were used: a vegetable emulsion, a synthetic solution and a integral oil. the variables analyzed during and after the grinding process were the grinding force, the superficial roughness, the acoustic emission (ea), the temperature of the piece and the g ratio (relationship between the volume of material removed from the piece and the volume worn off the grinding wheel). the integral oil showed the best performance relative to the following output variables: ea, cutting force and g ratio. the vegetal emulsion was the fluid that best dissipated heat from the cutting region.
Analysis of the cutting fluid influence on the deep grinding process with a CBN grinding wheel
Fusse Ronaldo Yoshinobu,Fran?a Thiago Valle,Catai Rodrigo Eduardo,Silva Leonardo Roberto da
Materials Research , 2004,
Abstract: The application of cutting fluid in a deep grinding process is becoming more and more important, mainly where the cutting fluids are used as an "external" agent to the grinding conditions. The role of the fluid in grinding operations is in refrigeration of the workpiece, removal of the shavings, lubrication of the grinding zone, and refrigeration and cleaning of the wheel. The efficiency of a cutting fluid will depend mainly of the type of fluid that will be used. In this work, the influences of the type of cutting fluid used in a deep grinding process of the steel VC131 using CBN grinding wheel are analyzed. Three different types of cutting fluids were used: a vegetable emulsion, a synthetic solution and a integral oil. The variables analyzed during and after the grinding process were the grinding force, the superficial roughness, the acoustic emission (EA), the temperature of the piece and the G ratio (relationship between the volume of material removed from the piece and the volume worn off the grinding wheel). The integral oil showed the best performance relative to the following output variables: EA, cutting force and G ratio. The vegetal emulsion was the fluid that best dissipated heat from the cutting region.
磨粒排布对加压内冷却砂轮磨削性能的影响
Effect of Abrasive Arraying Forms on the Grinding Performance of a Pressurized Internal-cooling Grinding Wheel
 [PDF]

彭锐涛,李仲平,唐新姿,周专
- , 2018,
Abstract: 考虑磨粒排布方式对砂轮磨削效率和性能有重要影响,设计制备磨粒无序和有序排布的加压内冷却砂轮,利用砂轮表面形貌检测和图像识别技术,建立砂轮磨削GH4169高温合金的三维有限元模型。采用不同磨粒排布的砂轮开展磨削GH4169高温合金的实验研究,对比分析磨削力、磨削温度、加工表面粗糙度以及表面微观形貌,研究磨粒无序和有序两种排布方式对砂轮磨削性能的影响。结果表明:对于加压内冷却砂轮而言,相对磨粒无序排布,磨粒有序排布方式能获得更优良的加工表面质量,磨削力、磨削温度和表面粗糙度均降低,且工件表面形貌更加规则完整。
In view of the effect of the abrasive arraying forms on the grinding efficiency and performance, the pressurized internal-cooling grinding wheels with random or ordered abrasive are designed and prepared. Based on the surface morphology detection technology and image identification technology, the 3D finite element model for grinding superalloy GH4169 is established. The grinding experiments of superalloy GH4169 are performed by adopting the prepared wheels, the effects of the abrasive arraying forms on the grinding performance are revealed, grinding force, temperature, machined surface roughness and surface topography are studied. The results show that:compared with the wheel with random abrasive, wheel with ordered abrasive leads to better machined surface quality, smaller grinding force, lower grinding temperature and surface roughness, moreover cleaner surface morphology
磨料表面微氧化对cBN磨具磨削性能的影响
Effect of the cBN Grit Surface Oxidation on Grinding Performance of the Vitrified cBN Tool
 [PDF]

鲍崇高,宋奕侨,侯书增,杨兴化,杨建锋,姚文静
- , 2015, DOI: 10.7652/xjtuxb201502021
Abstract: 为了解决陶瓷结合剂cBN磨具在高速磨削的过程中易发生断裂以至于失效的问题,提高cBN磨具材料的磨削性能,采用微氧化技术对cBN磨粒进行了表面处理,研究了cBN磨粒表面微氧化对cBN磨具中磨粒与结合剂间界面结合方式、界面结合力、磨具强度以及磨具磨削磨损的影响规律,并分析了磨具磨削磨损失效机制。结果表明:表面微氧化后的cBN磨粒表面氧化膜的成分是B2O3;因B2O3与结合剂组分发生反应致使结合面两侧产生元素互扩散,使得陶瓷结合剂与cBN磨粒界面间的机械结合方式转为化学结合方式;与cBN磨粒未经过氧化的磨具相比,经过表面氧化的cBN磨粒制备的磨具中陶瓷结合剂与cBN磨粒结合面剪切力提高了2??5倍,磨具抗弯强度提高了18%,且磨削磨损性能提高了2??6倍;cBN磨粒与结合剂结合力的提高可以使磨具强度提高,磨具磨削磨损时随着磨削力增大磨粒不易脱落,并逐渐发生自锐,从而降低磨具的损耗,提高磨削效率。
The surfaces of cBN abrasive particles are treated by micro??oxidation to solve the ceramic bond cBN grinding tool fracture failure problem that occurs during high??speed grinding and to improve the grinding performance of the cBN grinding tool material. The influence of cBN abrasive particles surface micro??oxidation to the interfacial bonding method, the interfacial bonding strength, the cBN tool strength and the cBN tool grinding performance are studied. And the wear failure mechanism of the cBN tool is analyzed. The results show that the oxide film component on cBN abrasive particle surface is B2O3. Element mutual diffusion at the interface occurs through the react between B2O3 and binder components, and the interface bonding between vitrified bonds and cBN abrasive is transformed from mechanical bond to chemical bond. Comparisons with the grinding tool without abrasive particle oxidation show that the interface shear stress of the grinding tool with abrasive particle oxidation increases 2??5 times while the bending strength has a 18% increase and the grinding wear resistance improves 2??6 times. The improvement of the combination between cBN abrasive particle and binding agent could make abrasive self??sharpening happen rather than shedding when grinding force increases. In that way, the loss of grinding tools decreases while the grinding efficiency increases
Analysis of the performance of superabrasive and alumina grinding wheels with different bonds and machining conditions
Bianchi, Eduardo Carlos;Aguiar, Paulo Roberto de;Monici, Rodrigo Daun;Daré Neto, Luiz;Silva, Leonardo Roberto da;
Materials Research , 2003, DOI: 10.1590/S1516-14392003000200020
Abstract: this paper presents a review of researches on cbn (cubic boron nitride) grinding wheels with the purpose of identifying the state of art in abrasive machining and serving as the basis for future researches and laboratory tests. the scientific studies investigated here report on interesting results involving grinding, published by brazilian and foreign authors. the methods and the results are presented and discussed. in addition, a grinding setup is presented which provides more reliable experimental results about the surface integrity of fragile materials. this setup was obtained for grinding tests in several grinding conditions during the wheel service life, using alumina and vitrified and resin bond cbn grinding wheels. results of cutting force, surface roughness and g ratio are also presented and discussed. they confirm the excellent machining capacity of the cbn wheel, with stable behavior in cutting force and roughness results during the tests. the g ratio values are in agreement with the results found by other researchers.
Analysis of the performance of superabrasive and alumina grinding wheels with different bonds and machining conditions
Bianchi Eduardo Carlos,Aguiar Paulo Roberto de,Monici Rodrigo Daun,Daré Neto Luiz
Materials Research , 2003,
Abstract: This paper presents a review of researches on CBN (cubic boron nitride) grinding wheels with the purpose of identifying the state of art in abrasive machining and serving as the basis for future researches and laboratory tests. The scientific studies investigated here report on interesting results involving grinding, published by Brazilian and foreign authors. The methods and the results are presented and discussed. In addition, a grinding setup is presented which provides more reliable experimental results about the surface integrity of fragile materials. This setup was obtained for grinding tests in several grinding conditions during the wheel service life, using alumina and vitrified and resin bond CBN grinding wheels. Results of cutting force, surface roughness and G ratio are also presented and discussed. They confirm the excellent machining capacity of the CBN wheel, with stable behavior in cutting force and roughness results during the tests. The G ratio values are in agreement with the results found by other researchers.
Estudo comparativo entre a agressividade superficial obtida na retifica??o com rebolos de óxido de alumínio e CBN, fabricados com ligantes resinóide e vitrificado
Bianchi, E. C.;Monici, R. D.;Neto, L. D.;Aguiar, A. R. de;Guermandi, L. G.;
Ceramica , 2011, DOI: 10.1590/S0366-69132011000400010
Abstract: this paper presents a study of the grinding wheel sharpness (cutting ability). grinding is a precision machining process which is widely used in the manufacture of components requiring fine tolerances and smooth surfaces. in grinding, the abrasive tool is the grinding wheel, which is basically compounded by the core, the bond and the abrasive grains. the tools tested in this research were conventional (al2o3) and superabrasive (cbn) grinding wheels. among the superabrasive ones, three specific bond types were tested: resin, vitrified and high performance resin bond. consequently, it was possible to evaluate the comparative cutting ability among the different types of grinding wheels tested. so the conventional wheel (al2o3) presented the highest sharpness.
The Effects of Wear upon the Axial Profile of a Grinding Wheel in the Construction of Innovative Grinding Wheels for Internal Cylindrical Grinding  [PDF]
K. Nadolny,B. S?owiński
Advances in Tribology , 2011, DOI: 10.1155/2011/516202
Abstract: The article describes the effects of wear upon the axial profile of a grinding wheel in the axial cylindrical grinding processes. This mechanism was used to develop a grinding wheel with zone diversified structure made of microcrystalline sintered corundum abrasive grains and vitrifies bond. Such a grinding wheel is characterized by the conical rough grinding zone that is made by grains of a relatively large size, and a cylindrical finish grinding zone with grains of a smaller size and can be used in the single-pass grinding processes. Investigative tests conducted using newly-developed grinding wheels were described. Investigations were operated in the single-pass internal cylindrical grinding process of 100Cr6 steel. A comparison of results obtained using a zone diversified structure grinding wheel, with reference to a grinding wheel with grains of one size, were given. The analysis provides the roughness of the grinded surface, the grinding power, as well as chosen indicators of grinding efficiency. Experimental results obtained with use of a zone-diversified grinding wheel, built from relatively cheap grains of microcrystalline sintered corundum, showed that it is possible to obtain large material removal rate up to approximately 24?mm3/s and high quality of machined surface ( ?μm). 1. Introduction Grinding is a method of producing technical surfaces with great precision and fineness using tools made from thousands of little grains of a hard material (aloxite, silicon carbide) or a very hard material (diamond, cubic boron nitride), bonded appropriately [1]. The great mechanical load and high temperature in the contact area between the tool and the ground material gives rise to tribological processes (frictional, chemical, diffusion, adhesion) which causes the quick wear of the abrasive grains and as a consequence the loss of the cutting ability of the tool [1–3]. There are a wide range of experiments underway that involve the reduction of these processes by different types of modifications to the construction of the grinding tools [2–5]. Most of these modifications involve the changing of parts, relating to a chosen aspect of the work, for example, a change of the abrasive material, bonding material, technology, tool structure and so forth. This paper describes the complex (system) approach to improving grinding tools—Figure 1. Figure 1: Procedures for designing modernized grinding tools with specified types of modifications. Of the many issues surrounding the decision-making processes in the area of technological developments, one is particularly
Experimental investigation of abrasive electrodischarge grinding of Ti6Al4V titanium alloy  [PDF]
R. ?wi?cik
Journal of Achievements in Materials and Manufacturing Engineering , 2009,
Abstract: Purpose: This work is focused on determination of effects of grinding conditions on effectiveness of abrasive electrodischarge grinding (AEDG) process applied for removal of machining allowance and forming of surface geometrical texture (SGT). These results were compared with one obtained for conventional grinding.Design/methodology/approach: The experimental investigations of deep-seated surface grinding of Ti6Al4V titanium alloy using CBN grinding wheel with metal bond were the ground for this elaboration. The effectiveness of AEDG process was assessed based on specific tangential grinding force and energy of spark electric discharge and machining results were estimated on geometrical structure parameters.Findings: The effectiveness of machining allowance removal depended on conditions of AEDG process. Significant differences in SGT formed by AEDG process and conventional grinding were revealed.Practical implications: Abrasive electrodischarge grinding is useful to be particularly suitable for efficient and effective grinding of very hard structural materials such as high-alloy steel, sintered carbides, metal-based composite materials etc.Originality/value: AEDG experiments were carried out using the typical surface finishing grinder and especially adapted generator of spark discharge pulses. The majority of such experiments in the world were performed with the electrodischarge machine tool equipped with extra grinding wheel mounted on the grinding pin and functioning as one of the electrodes put into operation via pneumatic drive.
Análise do comportamento da microestrutura de materiais endurecidos retificados com rebolos de CBN
Bianchi, Eduardo Carlos;Monici, Rodrigo Daun;Silva, Eraldo Jannone da;Aguiar, Paulo Roberto de;Valarelli, Ivan De Domenico;
Materials Research , 2000, DOI: 10.1590/S1516-14392000000400009
Abstract: cbn grinding wheels are superabrasive tools, with cutting ability higher than the conventional ones, specially used for grinding dtg (difficult to grind) materials. due to the higher hardness and thermal conductivity of the cbn superabrasive grains, when compared with conventional abrasive grains, the use of cbn tools reduce the grinding temperatures decreasing the probability of workipece?s thermal damage. these proprieties of cbn grains permit lowering the energy partition because less heat is generated during grinding and much heat is dissipated through the grinding wheel instead of through the workpiece. this paper shows a research about the microstructural changes in the ground subsurface and the differences in the superficial integrity when using two types of superabrasive grinding wheels, manufactured with vitrified and resin bonds, analyzed in different cutting conditions. the ground material was the vc 131 steel, hardened and tempered. were not observed microstructural changes in the subsurface ground with the two types of tools. as a result, the use of different types of the bonding do not affect the surface integrity neither resulted in microstructural changes, because the maximum temperatures measured in the grinding zone were lower than 125 °c, much less than the required level to cause microstructural changes.
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