Handbook of Machining with Grinding Wheels

The results of grinding are highly dependent on conditions of workpiece removal process. The material is removed by an unspecified number of abrasive grains of irregular shape and random distribution on the grinding wheel active surface. The interaction between the abrasive grain and the workpiece can be divided into three stages: (i) rubbing, (ii) ploughing and (iii) chip formation. Reciprocal contribution of each stage is dependent on the properties of the workpiece, the grinding parameters, the friction condition between the abrasive grain and the workpiece and the shape of the grains. In the article, the results of numerical and experimental process in the analysis of grinding of Ti-6Al-4V titanium alloy, using a conventional grinding wheel and a newly developed grinding wheel with aggregates of grains, were presented. The analysis of influence of the geometric parameters of the abrasive aggregates and the abrasive grains on the effectiveness of the workpiece removal process is presented. The effects of the geometrical parameters of grains and abrasive aggregates in direction of motion as well as in transversal direction on the size of ridges were determined. It has been observed that increase of the length of sideway material displacement results in the decrease of ridge formation. The results of a numerical analysis were confirmed by experimental research. The analysis of the impact of utilization of abrasive aggregates on the grinding forces, grinding-specific energy and surface roughness was performed. The impact of abrasive aggregates on the decrease of grinding forces and specific energy and the increase of quality of ground surface was observed.

Section: Introductionmentioning

confidence: 99%

Performance evaluation of the grinding wheel with aggregates of grains in grinding of Ti-6Al-4V titanium alloy

Kacalak

Lipiński

Bałasz

et al. 2017

“…d S1012A-AE-150 -12 processing of difficult-to-cut materials such as titanium (e.g. reduces friction between abrasive grain and material, removes significantly more heat (and does it more rapidly) than air cooling, prevents heat generation by lubricating the interface between the tool's cutting edge and the chip) [50] and decreases forces in the grinding zone (Fig. 15)).…”

Section: Acoustic Emission and Force Signalsmentioning

confidence: 99%

The estimation of machining results and efficiency of the abrasive electro-discharge grinding process of Ti6Al4V titanium alloy using the high-frequency acoustic emission and force signals

Sutowski

Święcik

2017

The paper presents the results obtained for abrasive electro-discharge grinding (AEDG) of Ti6Al4V titanium alloy with the use of super hard grinding wheels of cubic boron nitride with a metal bond. The experimental investigations were focused on process monitoring for sharp and worn grinding wheels. For the evaluation of the grinding process, the grinding force amplitude and a few descriptors of the high-frequency stress waves were investigated in both time and frequency domains. The results show that during the AEDG, specific elastic waves are generated. Since these waves have characteristic amplitudes, frequencies, and other different descriptors dependent on the current grinding wheel cutting ability and discharge parameters, they can be applied to estimate a statistically significant regression function. For each measurement signal, a few statistical features are calculated and used as input for data selection and classification procedures. Registration and classification of forces and acoustic emission signals can be used to analyse the abrasive electro-discharge grinding process and allow for the determination of the machining results and the lifespan of super hard grinding wheels.

“…This is another factor impeding the heat dissipation from the grinding zone in the described process, which contributes to generation of grinding defects (undesired tensile residual stresses of workpiece surface layer, microfractures, grinding burns, etc.) [1,2].…”

Section: Introductionmentioning

confidence: 99%

“…These conditions make internal cylindrical grinding extremely demanding for grinding wheels, especially in the context of their durability and operational time. The mechanical energy, introduced into the grinding process, resulted from the tool and the machined material's relative movement and is mostly transformed into heat [1,2]. This causes a high thermal load for the grinding zone resulting from friction and deformation phenomena accompanying chip formation and material removal.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

A multi-criteria methodology for effectiveness assessment of internal cylindrical grinding process with modified grinding wheels

Nadolny

Al-Obaidi

2016

One of the possible engineering solutions in developing grinding technology is modifying the structure of the grinding wheels. This solution is applicable and feasible for industrial conditions as it does not require interfering with the construction of the grinding machine. This article presents an important aspect of the development of new grinding wheels, which uses multiple criteria to evaluate their effectiveness in the grinding process. An analysis of previously used methods of grinding effectiveness evaluation was performed. A number of criteria for evaluating the most important expenditures and effects of these processes were highlighted. Next, a comparative evaluation of effectiveness of the six suggested grinding wheel modifications with sintered microcrystalline corundum grains and ceramic bond was performed. These grinding wheels were characterized by the following structural modifications: zone-diversified structure, modification of the bond microstructure, microdiscontinuities of the grinding wheel active surface, sandwich structure with a centrifugal system for provision of the coolant into the grinding zone as well as impregnated grinding wheel. Additionally, a grinding wheel whose structure was composed of a number of modifications was considered. The essential advantages and disadvantages of the structural types of small-sized grinding wheels for peripheral grinding were determined. The results of the analysis of the effectiveness of the suggested solutions showed that it is possible to adjust the grinding wheel construction to the expected results of the given grinding operation as well as the technological conditions. It is also possible to combine these modifications in order to obtain additional synergetic effect of their positive influence on the grinding process.