Effect of glass-crystalline and amorphous binder application to abrasive tools made of microcrystalline alumina grains type SG

Int J Adv Manuf Technol

2014

This article presents the results from a traverse internal cylindrical grinding process conducted using grinding wheels with sol-gel alumina abrasive grains and varying volumes of glass-ceramic vitrified bond. The aim was to determine how changing the bond volume within the range of V b =11.5-14.5 % influenced the wear phenomenon of the microcrystalline sintered corundum abrasive grains and the ceramic bond bridges with glass-crystalline structure. The paper presents grinding wheels with conic chamfer and the most important wear phenomena of the grinding wheel components occurring in the area of contact between the tool and the workpiece material. The work includes the methodology of the experimental tests on the traverse internal cylindrical grinding of bearing rings made from steel 100Cr6 (62±2 HRC). A wide range of test results were analyzed, including machined surface roughness parameters (Ra, Rz, Sm, Δa), grinding power, grinding wheel volumetric wear V s , material removal V w , G-ratio, root-mean-square roundness deviation from mean circle (Δ, rms), grinding wheel edge wear, grinding wheel microtopography parameters (Sa, St, Sdr, Sds), and SEM images of the wear marks on the grinding wheel active surface. The dominant wear phenomena of the grinding wheels with conic chamfer and the influence of the bond volume share on its intensity were experimentally determined. The results show that the decrease in bond volume from V b =14.5 to 11.5 % increases the grinding wheel life by twofold. This was due to a decrease in abrasive wear and plastic flow phenomena and to a greater fracture wear (mostly fatigue and thermal-fatigue). These events led to a periodic shedding of the oxide layer and the plastically deformed grain layer and also revealed the crystals' sharp edges, located below the plastically deformed surface layer.

Section: Glass-crystalline Bondmentioning

confidence: 99%

Wear phenomena of grinding wheels with sol–gel alumina abrasive grains and glass–ceramic vitrified bond during internal cylindrical traverse grinding of 100Cr6 steel

Int J Adv Manuf Technol

2014

“…The modifications made so far mainly concern increasing the openness of the abrasive tool structure, among others by using special fillers and spherical corundum grains [19]. New types of crystalline ceramic binders have also been developed, which enable the regulation of intensity and rate of the wear and self-sharpening of tools [5][6][7]. There are also developed grinding wheels with micro-and macrodis-continuities of their active surfaces [9] as well as various impregnating agents preventing chip adhesion and bonding of tool surfaces [13,16,17].…”

Section: Introductionmentioning

confidence: 99%

Construction and technical modification of grinding wheels for internal cylindrical grinding using scamper method of creative innovation design

Plichta

Journal of Mechanical and Energy Engineering

Gierszewska³

2018

Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 (CC BY 4.0) International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. Abstract: This article describes a case study of an application of the method of creating innovations called SCAMPER for the development of new abrasive tools designed for machining of hard-to-cut materials. The SCAMPER method is used for innovative transformations of existing products, aimed at a modernization of their design, a construction and an extension of functions. This method was used in the procedure of modifying abrasive tools and it permitted a generation of a set of innovative solutions in this field. The methodology made it also possible to logically organize individual creative activities supported by the previously accumulated theoretical and experimental knowledge.

“…Glass-crystalline bonds have polymicrocrystalline structure and contain a so-called glassy residual, i.e., the residual glass phase. It is obtained from glass, which, as a result of phase transformations that take place during controlled heat processing, is changed into small-grained polycrystalline material with the required properties [38,39]. The application of glasscrystalline bonds with a different microstructure and level of crystallinity allows for, among other things, a limitation in the propagation of cracks in the bond, as well as controlling the process of bond bridges wear during grinding wheel operation [40].…”

Section: Introductionmentioning

confidence: 99%

Effect of vitrified bond microstructure and volume fraction in the grinding wheel on traverse internal cylindrical grinding of Inconel® alloy 600

Int J Adv Manuf Technol

Herman

2015

The following article examines the influence of glass-crystalline bond in grinding wheels with grains made from microcrystalline aluminum oxide, and specifically its effect upon the values of selected operational indicators in the process of traverse internal cylindrical grinding of surfaces made from Inconel® alloy 600. The experimental test results obtained showed that changes in the bond phase composition, including its microstructure and volume share in the grinding wheel, has significant influence upon the workpiece surface roughness, grinding power, and other basic phenomena within the grinding zone. It was proven that the heat and physicalmechanical properties of the bonds have considerable influence on the mechanism of the grinding wheel components (abrasive grains and bond bridges) wear mechanisms. The phenomena occurring in the area of contact between the grinding wheel active surface and the workpiece surface requires on, among other things, the temperature at which the bond softens, initial bond hardness, the critical coefficient of grain strain intensity K Ic , the crystalline phases generated, and the volumetric share of the amorphous and crystalline phases in the bridges binding the abrasive grains.