scholarly journals A Method and Device for Automated Grinding of Small Ceramic Elements

Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7904
Author(s):  
Wojciech Kacalak ◽  
Dariusz Lipiński ◽  
Filip Szafraniec ◽  
Błażej Bałasz
Keyword(s):  
Small Area ◽  
High Efficiency ◽  
Grinding Wheel ◽  
Grinding Wheels ◽  
Sequential Processing ◽  
Abrasive Grains ◽  
Automated Method ◽  
Developed Surface ◽  
Resin Binder ◽  
Diamond Abrasive

The paper describes an automated method for grinding small ceramic elements using a hyperboloid wheel. The problem of automating the process of machining elements made of nonmagnetic materials with a small area and low height has been solved. Automation of the grinding process was possible thanks to automatic clamping of workpieces in the machining zone and sequential processing by a specified number of grinding wheels. The workpieces were passed through successive machining zones. The division of the allowance of individual grinding wheels was made taking into account the characteristics of the workpieces and the requirements for the results of the machining. Obtaining a long grinding zone and the effect of automatic clamping of the workpieces was possible due to the inclination of the grinding wheel axis in relation to the plane of movement of the workpieces. Innovative aggregate grinding wheels were used for grinding. The aggregates containing diamond abrasive grains, connected with a metal bond, were embedded in the porous structure of the resin bond. The aggregates ensured high efficiency of grinding, and their developed surface contributed to good holding in the resin binder. The durability of grinding wheels was 64 h, which enables the machining of 76,000 ceramic elements.

Experimental Investigation on Bronze-Bonded CBN Formed Grinding Wheel by Means of Electro-Discharging Dressing

2016 ◽  
Vol 1136 ◽  
pp. 97-103
Author(s):  
Jian Wu Yu ◽  
Li Hua He ◽  
Hong Luo ◽  
Shao Hui Yin
Keyword(s):  
Electrical Discharge ◽  
High Efficiency ◽  
Pulse Current ◽  
Precision Machining ◽  
Grinding Wheel ◽  
Grinding Wheels ◽  
Abrasive Grains ◽  
Finishing Process ◽  
Discharge Parameters ◽  
Cbn Grinding Wheel

High-efficiency and precision machining of complicated components can be realized by using metal-bonded CBN grinding wheel. However, the difficulty in dressing those superabrasive grinding wheels is one of the main obstructions to popularize its application in industry. Different from the traditional methods, the aim of the paper is to investigate the electro-discharge dressing of bronze-bonded CBN formed grinding wheel. Based on the analysis of electrical discharge parameters and grinding performance, the results show that electro-discharge dressing of CBN formed grinding wheel is feasible. With the increase of pulse duration, pulse voltage and pulse current, the dressing efficiency is increasing, more abrasive grains are protruding, but surface topography of grinding wheel is worsen. Therefore, grinding tests show that, in order to get the dressing quality better and keep the dressing efficiency higher, the bigger electrical discharge parameters are chosen for rough dressing process and the smaller ones are chosen for finishing process.

Grinding of Carbon/Epoxy Composites Using Electroplated CBN Wheel with Controlled Abrasive Clusters

2008 ◽  
Vol 389-390 ◽  
pp. 24-29 ◽  
Author(s):  
H.P. Yuan ◽  
Hang Gao ◽  
Yong Jie Bao ◽  
Yong Bo Wu
Keyword(s):  
Epoxy Composite ◽  
Epoxy Composites ◽  
Grinding Wheel ◽  
The Novel ◽  
Grinding Wheels ◽  
Grinding Forces ◽  
Abrasive Grains ◽  
Dry Grinding ◽  
Conventional Grinding ◽  
Wheel Loading

Aiming at solving the problems of wheel loading in dry grinding of Carbon/Epoxy composite materials, a novel electroplated grinding wheel with controlled abrasive cluster was developed, in which the diameter of clusters is in Φ0.2 mm to Φ1.0 mm and the interspace between them is about 0.5 mm to 1.0 mm. A conventional electroplated grinding wheel with abrasive grains distributed randomly was fabricated in the same way. The comparison experiments involving C/E composite were conducted on a vertical spindle grinder with the novel and conventional grinding wheels. The results show that the grinding forces of novel wheel developed is more lower though little larger surface roughness, and the wheel loading phenomenon is markedly decreased compared with conventional electroplated wheel.

Characterization of High-Speed Alumina Abrasive Grinding Wheel

2020 ◽  
Vol 405 ◽  
pp. 365-369
Author(s):  
Zina Pavloušková ◽  
David Jech ◽  
Pavel Komarov ◽  
Ivana Ročňáková ◽  
Lucie Dyčková ◽  
...  
Keyword(s):  
High Speed ◽  
Raw Materials ◽  
Initial Mixture ◽  
Grit Size ◽  
Grinding Wheel ◽  
Grinding Wheels ◽  
Abrasive Grains ◽  
Analysis Technique ◽  
High Speed Grinding

The high-speed grinding wheel can be defined as a self-sharpening composite structural tool composed from abrasive grains held in a specific binder. The main properties of grinding wheels depend on the type of abrasive elements, grit size, grade, binder and the resulting structure, which is influenced by several crucial technological processing steps. Preparation of an initial mixture of abrasive particles together with permanent binder’s mixture and temporary binder followed by pressing and high-temperature sintering is the essential technological step in the manufacturing of high-quality grinding wheels. High demands placed on functionality and quality together with constantly increasing effort to improve existing properties of grinding tools require detailed characterization of all input raw materials. For further research and development is crucial know, how each technological step can influence the final quality of the product. This contribution is focused on the characterization of four alumina abrasives with different grit size and two in chemical composition different binder mixtures which were used for the production of two different high-speed grinding wheels. Initial abrasive grains, binders and metallographic samples of high-speed grinding wheels were evaluated by means of scanning electron microscopy. The porosity of grinding wheels with different binding agents was also determined ustilizing digital image analysis technique.

Effective thermal properties of grinding wheels and grains

1998 ◽  
Vol 212 (8) ◽  
pp. 661-669 ◽  
Author(s):  
M N Morgan ◽  
W B Rowe ◽  
S C E Black ◽  
D R Allanson
Keyword(s):  
Thermal Conductivity ◽  
Thermal Properties ◽  
Boron Nitride ◽  
Thermal Performance ◽  
Cubic Boron Nitride ◽  
Energy Partitioning ◽  
Grinding Wheel ◽  
Grinding Wheels ◽  
Abrasive Grains ◽  
Effective Thermal Properties

The thermal properties of the grinding wheel are required for energy partitioning in grinding. This paper describes an investigation of the effective thermal properties of alumina and cubic boron nitride (CBN) grinding wheels. Results are presented for a novel sensor that was designed to measure the bulk thermal properties of grinding wheel samples. The effective bulk thermal properties of the grinding wheel and the effective thermal properties of the abrasive grains were also investigated. It was found that the bulk thermal property is dominated by the properties of the bond and does not account for the improved thermal performance of CBN compared with alumina. Values of the effective thermal conductivities for alumina and CBN abrasive grains are therefore proposed. It is concluded that the effective thermal conductivity of the grains is best obtained inversely from grinding experiments.

Development on Micro Precision Truing Method of ELID-Grinding Wheel (1st Report: Principle & Fundamental Experiments)

2005 ◽  
Vol 291-292 ◽  
pp. 207-212 ◽  
Author(s):  
Hitoshi Ohmori ◽  
Shao Hui Yin ◽  
Wei Min Lin ◽  
Yoshihiro Uehara ◽  
Shinya MORITA ◽  
...  
Keyword(s):  
High Precision ◽  
High Efficiency ◽  
High Hardness ◽  
Experimental Results ◽  
Grinding Wheel ◽  
Grinding Process ◽  
Grinding Wheels ◽  
Elid Grinding ◽  
High Toughness ◽  
Diamond Grinding

Metal bonded diamond grinding wheels are widely used in the grinding process, especial in ELID grinding. However, truing is difficult owing to the high toughness of metal bond materials and high hardness of diamond abrasives. To realize high precision and high-efficiency truing, we propose a new micro-truing method consisting of electro-discharge truing and electrolysis-assisted mechanical truing in this paper. The process principle and fundamental experimental results are introduced, and the truing performance is discussed. Research results show that the proposed new method is effective for truing metal bonded diamond grinding wheels.

An Investigation of Grinding Wheel Cutting Edges

1964 ◽  
Vol 86 (4) ◽  
pp. 371-382 ◽  
Author(s):  
H. Tsuwa
Keyword(s):  
Electron Microscope ◽  
Microscopic Observation ◽  
Phase Contrast ◽  
Grinding Wheel ◽  
Grinding Wheels ◽  
Abrasive Grains ◽  
Contrast Microscope ◽  
New Apparatus ◽  
Grinding Operations ◽  
Dressing Action

A new apparatus for microscopic observation and tracing of cutting edges of a wheel has been developed. The use of this apparatus allows us to visually witness the behavior of abrasive grains during the grinding operation. A phase-contrast microscope, as well as an electron microscope has been used with the new apparatus in this investigation. A method of calculating effective grain spacing to show distribution of cutting edges, as well as the cutting edge ratio to known worn conditions of grains has been completed. These aforementioned values for various grinding wheels have been studied in grinding operations and the changing aspects of them have been noted. Through these experiments, we have had helpful suggestions about grinding mechanisms; there is no self-dressing action of grains in the usual grinding work; sliding of the cutting edges takes place in the grinding, and wear of the grinding is increased by this action.

The method of assessment of the grinding wheel cutting ability in the plunge grinding

2012 ◽  
Vol 2 (3) ◽  
Author(s):  
Krzysztof Nadolny
Keyword(s):  
Working Conditions ◽  
Comparative Assessment ◽  
Grinding Wheel ◽  
Grinding Process ◽  
Grinding Wheels ◽  
Plunge Grinding ◽  
Abrasive Grains ◽  
Ceramic Bond ◽  
Method Of Assessment ◽  
Grinding Kinematics

AbstractThis article presents the method of comparative assessment of the grinding wheel cutting ability in the plunge grinding kinematics. A new method has been developed to facilitate multicriterial assessment of the working conditions of the abrasive grains and the bond bridges, as well as the wear mechanisms of the GWAS, which occur during the grinding process, with simultaneous limitation of the workshop tests range. The work hereby describes the methodology of assessment of the grinding wheel cutting ability in a short grinding test that lasts for 3 seconds, for example, with a specially shaped grinding wheel, in plunge grinding. The grinding wheel macrogeometry modification applied in the developed method consists in forming a cone or a few zones of various diameters on its surface in the dressing cut. It presents an exemplary application of two variants of the method in the internal cylindrical plunge grinding, in 100Cr6 steel. Grinding wheels with microcrystalline corundum grains and ceramic bond underwent assessment. Analysis of the registered machining results showed greater efficacy of the method of cutting using a grinding wheel with zones of various diameters. The method allows for comparative tests upon different grinding wheels, with various grinding parameters and different machined materials.

The effect of sulfurization on the grinding wheel cutting ability in the internal cylindrical grinding of nickel superalloys

2016 ◽  
Vol 231 (1) ◽  
pp. 140-154
Author(s):  
Krzysztof Nadolny ◽  
Walery Sienicki ◽  
Michał Wojtewicz
Keyword(s):  
Experimental Tests ◽  
Active Surface ◽  
Bearing Steel ◽  
Grinding Wheel ◽  
Nickel Superalloys ◽  
Grinding Wheels ◽  
Adhesive Properties ◽  
Plunge Grinding ◽  
Abrasive Grains ◽  
Internal Cylindrical Grinding

One possible way of preventing excessive growth of smearings/loads on the grinding wheel active surface is the introduction of compounds such as sulfur, graphite, or wax into the grinding wheel volume which exerts an active influence on adhesion during the process of impregnation. Limiting the formation of smearings/loads on the grinding wheel active surface is of crucial importance to achieve effective grinding of hard-to-cut materials (such as nickel superalloys) which are characterized by considerable ductility and a strong chemical affinity to abrasive grains, among other things. This article presents the results of experimental tests performed on plunge grinding and the influence of sulfur impregnation of grinding wheels on the smearing/load intensity on the grinding wheel active surface during the process of internal cylindrical plunge grinding of openings made from Inconel® alloy 600 and Incoloy® alloy 800HT®. Bearing steel 100Cr6 was included in the tests as a reference material. Grinding wheels were impregnated with a new method of gravitational sulfurization combined with centrifuging. The experiments carried out show that the adhesive properties of sulfur allowed for considerable limitation of smearing/loading of the grinding wheel active surface with machined material. This mainly concerned limiting the formation of the largest and most technologically undesirable smearings/loads of the intergranular spaces. The presence of sulfur in the grinding wheel volume had a minor influence on the intensity of smearings/loads in the microareas of the active abrasive grains’ apexes. The tests also showed an increase of 32%–49% in the value of parameter Sa in the surfaces ground with grinding wheels impregnated with sulfur for all the examined materials.

scholarly journals New Abrasive Materials and Their Influence on the Surface Quality of Bearing Steel After Grinding

10.14311/1598 ◽  
2012 ◽  
Vol 52 (4) ◽  
Author(s):  
Ondrej Jusko
Keyword(s):  
Surface Quality ◽  
Bearing Steel ◽  
Grinding Wheel ◽  
Grinding Process ◽  
Grinding Wheels ◽  
Abrasive Material ◽  
Abrasive Grains ◽  
Measurement Results ◽  
New Type

This paper focuses on the influence of various types of abrasive grains on cutting properties during the grinding process for bearing steel. In this experiment, not only conventional super-hard abrasive materials but also a new type of abrasive material were employed in grinding wheels. The measurement results were compared, and an evaluation was made of the cutting properties of the new abrasive material. The options were then evaluated for their practical applicability. The measurement results indicated that a grinding wheel with Abral and SG grains is the most suitable for grinding hardened bearing steel in order to achieve the best roughness and geometrical accuracy.

Potential for improving efficiency of the internal cylindrical grinding process by modification of the grinding wheel structure—Part I: Grinding wheels made of conventional abrasive grains

2016 ◽  
Vol 231 (4) ◽  
pp. 621-632 ◽  
Author(s):  
Krzysztof Nadolny ◽  
Witold Habrat
Keyword(s):  
Sol Gel ◽  
Active Surface ◽  
Positive Influence ◽  
Grinding Wheel ◽  
Grinding Process ◽  
Grinding Wheels ◽  
Abrasive Grains ◽  
Wide Range ◽  
Internal Cylindrical Grinding ◽  
Different Diameters

This article offers an overview of 14 grinding wheel construction modifications used in the peripheral grinding of flat-shaped internal and external cylindrical surfaces, when grinding wheels made of conventional abrasive grains are used (Al2O3, sol-gel alumina, SiC, etc.). The text contains characteristics of grinding wheels with mixed grains, glass-crystalline bond, a centrifugal provision of the coolant into the grinding zone, aggregate grains, zones of different diameters, radial rough grinding zone, extended finish grinding segments, active surface macro- and micro-discontinuities, as well as multiporous, impregnated (self-lubricating), sandwich, sectional and segment grinding wheels. Each of the presented structural modifications was described by giving construction scheme, used abrasive grains, range of applications, advantages as well as disadvantages. Modifications of the grinding wheel construction allow for effective improvement of both the conditions and the results of the grinding process. A wide range of the known modifications allows for their proper selection depending on the required criteria of effective evaluation and taking into account the specific characteristics of conventional abrasive grains. As a result, it is possible to obtain positive influence on a number of technological factors of the grinding process. The described modifications of the grinding wheel structure can be also an inspiration and the basis for creating new solutions in this field.

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