The Experts below are selected from a list of 1335 Experts worldwide ranked by ideXlab platform
Chedly Braham - One of the best experts on this subject based on the ideXlab platform.
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effects of abrasive type cooling mode and peripheral grinding wheel speed on the aisi d2 steel ground surface integrity
International Journal of Machine Tools & Manufacture, 2009Co-Authors: Brahim Ben Fathallah, Nabil Ben Fredj, Habib Sidhom, Chedly Braham, Yoshio IchidaAbstract:Abstract In this work the AISI D2 steel ground surface integrity was evaluated at different grinding conditions. Two sets of experiments were conducted. The first and the second sets are referred to as conventional grinding tests (CGTs) and high-speed grinding tests (HSGTs), respectively. For the CGTs two different types of abrasives (aluminium oxide and sol–gel alumina) and two cooling modes (oil-based grinding fluid and cryogenic cooling) were tested at a peripheral wheel speed vs=22 m/s. For the HSGTs, an electroplated cBN grinding wheel was used at a peripheral wheel speed ranging from 60 to 260 m/s. Experimental results show that the grindability and the surface integrity of the AISI D2 steel could be substantially improved by using the sol–gel grinding wheel and cooling by liquid nitrogen comparatively with conditions using aluminium oxide and cooling with oil-based grinding fluid. These conditions reduce the grinding force components, lower the level of tensile residual stresses and expand the range of Stock Removals Rate for which compressive residual stresses can be obtained. In this case the Stock Removal Rate could be increased 7 times and still having compressive residual stresses. These experimental results were further explored and it was possible to establish linear relationships between the specific energy and the amplitudes of the surface residual stresses when grinding under the CGTs conditions. This relationship is very useful for process control and optimization. Results of the HSGTs show that the highest levels of the compressive surface residual stresses were obtained at a peripheral wheel speed vs=120 m/s (σ∥=−520 MPa, σ⊥=−770 MPa). These values are much higher than those measured at the ground surface geneRated using the sol–gel grinding wheel and cooling by liquid nitrogen (σ∥=−295 MPa, σ⊥=−250 MPa). Further, the CGTs and HSGTs results were used to establish the burn-free and burn conditions in relation with the specific grinding energy. It was shown that condition using the sol–gel grinding wheel and cooling with liquid nitrogen and condition using cBN grinding wheel at peripheral wheel speed up to 180 m/s geneRate specific grinding energy that are significantly lower than the burning threshold energy.
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ground surface improvement of the austenitic stainless steel aisi 304 using cryogenic cooling
Surface & Coatings Technology, 2006Co-Authors: Nabil Ben Fredj, Habib Sidhom, Chedly BrahamAbstract:Grinding fluid selection is becoming increasingly constrained by environmental considerations, thus requiring the substitution of the conventionally used oil-based coolants. The work presented in this paper aims at evaluating the ground surface quality improvements of the austenitic stainless steel AISI 304 resulting from the application of cryogenic cooling. The evaluation is based on criteria related to grindability, surface integrity and corrosion resistance characterisation. Grinding experiments at an almost constant Stock Removal Rate were conducted under three different environments: dry, soluble oil and cryogenic cooling. The grindability results have shown that while the cryogenic cooling geneRates the lowest grinding temperature, no significant differences over the specific grinding force components were observed. As for the ground surface integrity, however, substantial improvements were realized. Indeed, by using the cryogenic cooling, a reduction of more than 40% of the surface roughness could be realized, a higher level of work hardening occurred, a lower level of tensile residual stress was measured and better resistances to stress corrosion cracking and pitting corrosion were noticed. These improvements in grindability and in surface integrity are particularly favoured by grinding conditions using high work speed and low depth of cut values. It is also shown that these improvements are essentially due to the reduction of the grinding temperature, which lowers the tensile residual stress and to the cryo-temperature, which favours the material Removal by shearing and limits the ground surface damage.
Nabil Ben Fredj - One of the best experts on this subject based on the ideXlab platform.
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effects of abrasive type cooling mode and peripheral grinding wheel speed on the aisi d2 steel ground surface integrity
International Journal of Machine Tools & Manufacture, 2009Co-Authors: Brahim Ben Fathallah, Nabil Ben Fredj, Habib Sidhom, Chedly Braham, Yoshio IchidaAbstract:Abstract In this work the AISI D2 steel ground surface integrity was evaluated at different grinding conditions. Two sets of experiments were conducted. The first and the second sets are referred to as conventional grinding tests (CGTs) and high-speed grinding tests (HSGTs), respectively. For the CGTs two different types of abrasives (aluminium oxide and sol–gel alumina) and two cooling modes (oil-based grinding fluid and cryogenic cooling) were tested at a peripheral wheel speed vs=22 m/s. For the HSGTs, an electroplated cBN grinding wheel was used at a peripheral wheel speed ranging from 60 to 260 m/s. Experimental results show that the grindability and the surface integrity of the AISI D2 steel could be substantially improved by using the sol–gel grinding wheel and cooling by liquid nitrogen comparatively with conditions using aluminium oxide and cooling with oil-based grinding fluid. These conditions reduce the grinding force components, lower the level of tensile residual stresses and expand the range of Stock Removals Rate for which compressive residual stresses can be obtained. In this case the Stock Removal Rate could be increased 7 times and still having compressive residual stresses. These experimental results were further explored and it was possible to establish linear relationships between the specific energy and the amplitudes of the surface residual stresses when grinding under the CGTs conditions. This relationship is very useful for process control and optimization. Results of the HSGTs show that the highest levels of the compressive surface residual stresses were obtained at a peripheral wheel speed vs=120 m/s (σ∥=−520 MPa, σ⊥=−770 MPa). These values are much higher than those measured at the ground surface geneRated using the sol–gel grinding wheel and cooling by liquid nitrogen (σ∥=−295 MPa, σ⊥=−250 MPa). Further, the CGTs and HSGTs results were used to establish the burn-free and burn conditions in relation with the specific grinding energy. It was shown that condition using the sol–gel grinding wheel and cooling with liquid nitrogen and condition using cBN grinding wheel at peripheral wheel speed up to 180 m/s geneRate specific grinding energy that are significantly lower than the burning threshold energy.
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ground surface improvement of the austenitic stainless steel aisi 304 using cryogenic cooling
Surface & Coatings Technology, 2006Co-Authors: Nabil Ben Fredj, Habib Sidhom, Chedly BrahamAbstract:Grinding fluid selection is becoming increasingly constrained by environmental considerations, thus requiring the substitution of the conventionally used oil-based coolants. The work presented in this paper aims at evaluating the ground surface quality improvements of the austenitic stainless steel AISI 304 resulting from the application of cryogenic cooling. The evaluation is based on criteria related to grindability, surface integrity and corrosion resistance characterisation. Grinding experiments at an almost constant Stock Removal Rate were conducted under three different environments: dry, soluble oil and cryogenic cooling. The grindability results have shown that while the cryogenic cooling geneRates the lowest grinding temperature, no significant differences over the specific grinding force components were observed. As for the ground surface integrity, however, substantial improvements were realized. Indeed, by using the cryogenic cooling, a reduction of more than 40% of the surface roughness could be realized, a higher level of work hardening occurred, a lower level of tensile residual stress was measured and better resistances to stress corrosion cracking and pitting corrosion were noticed. These improvements in grindability and in surface integrity are particularly favoured by grinding conditions using high work speed and low depth of cut values. It is also shown that these improvements are essentially due to the reduction of the grinding temperature, which lowers the tensile residual stress and to the cryo-temperature, which favours the material Removal by shearing and limits the ground surface damage.
Habib Sidhom - One of the best experts on this subject based on the ideXlab platform.
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effects of abrasive type cooling mode and peripheral grinding wheel speed on the aisi d2 steel ground surface integrity
International Journal of Machine Tools & Manufacture, 2009Co-Authors: Brahim Ben Fathallah, Nabil Ben Fredj, Habib Sidhom, Chedly Braham, Yoshio IchidaAbstract:Abstract In this work the AISI D2 steel ground surface integrity was evaluated at different grinding conditions. Two sets of experiments were conducted. The first and the second sets are referred to as conventional grinding tests (CGTs) and high-speed grinding tests (HSGTs), respectively. For the CGTs two different types of abrasives (aluminium oxide and sol–gel alumina) and two cooling modes (oil-based grinding fluid and cryogenic cooling) were tested at a peripheral wheel speed vs=22 m/s. For the HSGTs, an electroplated cBN grinding wheel was used at a peripheral wheel speed ranging from 60 to 260 m/s. Experimental results show that the grindability and the surface integrity of the AISI D2 steel could be substantially improved by using the sol–gel grinding wheel and cooling by liquid nitrogen comparatively with conditions using aluminium oxide and cooling with oil-based grinding fluid. These conditions reduce the grinding force components, lower the level of tensile residual stresses and expand the range of Stock Removals Rate for which compressive residual stresses can be obtained. In this case the Stock Removal Rate could be increased 7 times and still having compressive residual stresses. These experimental results were further explored and it was possible to establish linear relationships between the specific energy and the amplitudes of the surface residual stresses when grinding under the CGTs conditions. This relationship is very useful for process control and optimization. Results of the HSGTs show that the highest levels of the compressive surface residual stresses were obtained at a peripheral wheel speed vs=120 m/s (σ∥=−520 MPa, σ⊥=−770 MPa). These values are much higher than those measured at the ground surface geneRated using the sol–gel grinding wheel and cooling by liquid nitrogen (σ∥=−295 MPa, σ⊥=−250 MPa). Further, the CGTs and HSGTs results were used to establish the burn-free and burn conditions in relation with the specific grinding energy. It was shown that condition using the sol–gel grinding wheel and cooling with liquid nitrogen and condition using cBN grinding wheel at peripheral wheel speed up to 180 m/s geneRate specific grinding energy that are significantly lower than the burning threshold energy.
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ground surface improvement of the austenitic stainless steel aisi 304 using cryogenic cooling
Surface & Coatings Technology, 2006Co-Authors: Nabil Ben Fredj, Habib Sidhom, Chedly BrahamAbstract:Grinding fluid selection is becoming increasingly constrained by environmental considerations, thus requiring the substitution of the conventionally used oil-based coolants. The work presented in this paper aims at evaluating the ground surface quality improvements of the austenitic stainless steel AISI 304 resulting from the application of cryogenic cooling. The evaluation is based on criteria related to grindability, surface integrity and corrosion resistance characterisation. Grinding experiments at an almost constant Stock Removal Rate were conducted under three different environments: dry, soluble oil and cryogenic cooling. The grindability results have shown that while the cryogenic cooling geneRates the lowest grinding temperature, no significant differences over the specific grinding force components were observed. As for the ground surface integrity, however, substantial improvements were realized. Indeed, by using the cryogenic cooling, a reduction of more than 40% of the surface roughness could be realized, a higher level of work hardening occurred, a lower level of tensile residual stress was measured and better resistances to stress corrosion cracking and pitting corrosion were noticed. These improvements in grindability and in surface integrity are particularly favoured by grinding conditions using high work speed and low depth of cut values. It is also shown that these improvements are essentially due to the reduction of the grinding temperature, which lowers the tensile residual stress and to the cryo-temperature, which favours the material Removal by shearing and limits the ground surface damage.
Masana Kato - One of the best experts on this subject based on the ideXlab platform.
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Determination of waviness decrease Rate by measuring the frequency characteristics of the grinding force in centerless grinding
Journal of Materials Processing Technology, 2005Co-Authors: Yongbo Wu, Masana KatoAbstract:Abstract In centerless grinding, it is difficult to optimize the grinding conditions for minimizing the workpiece roundness error because of the high number of process parameters such as center height angle, blade angle, and Stock Removal Rate. We had previously proposed a function for evaluating grinding conditions, i.e., the waviness decrease Rate, in order to automatically select the optimum process parameters. In order to build a closed-loop control system for the process parameters, however, it is necessary to find a practical way to determine the waviness decrease Rate. In this paper, the relationship between the waviness decrease Rate and the dynamic components of the grinding force was investigated analytically. It was found that the frequency characteristics of the waviness decrease Rate show a similar tendency to those of the grinding force. A grinding force measurement system was built and experiments for measuring the frequency characteristics of the grinding force were carried out. As a result, it was confirmed that the waviness decrease Rate can be determined by measuring the frequency characteristics of the grinding force.
Yoshio Ichida - One of the best experts on this subject based on the ideXlab platform.
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effects of abrasive type cooling mode and peripheral grinding wheel speed on the aisi d2 steel ground surface integrity
International Journal of Machine Tools & Manufacture, 2009Co-Authors: Brahim Ben Fathallah, Nabil Ben Fredj, Habib Sidhom, Chedly Braham, Yoshio IchidaAbstract:Abstract In this work the AISI D2 steel ground surface integrity was evaluated at different grinding conditions. Two sets of experiments were conducted. The first and the second sets are referred to as conventional grinding tests (CGTs) and high-speed grinding tests (HSGTs), respectively. For the CGTs two different types of abrasives (aluminium oxide and sol–gel alumina) and two cooling modes (oil-based grinding fluid and cryogenic cooling) were tested at a peripheral wheel speed vs=22 m/s. For the HSGTs, an electroplated cBN grinding wheel was used at a peripheral wheel speed ranging from 60 to 260 m/s. Experimental results show that the grindability and the surface integrity of the AISI D2 steel could be substantially improved by using the sol–gel grinding wheel and cooling by liquid nitrogen comparatively with conditions using aluminium oxide and cooling with oil-based grinding fluid. These conditions reduce the grinding force components, lower the level of tensile residual stresses and expand the range of Stock Removals Rate for which compressive residual stresses can be obtained. In this case the Stock Removal Rate could be increased 7 times and still having compressive residual stresses. These experimental results were further explored and it was possible to establish linear relationships between the specific energy and the amplitudes of the surface residual stresses when grinding under the CGTs conditions. This relationship is very useful for process control and optimization. Results of the HSGTs show that the highest levels of the compressive surface residual stresses were obtained at a peripheral wheel speed vs=120 m/s (σ∥=−520 MPa, σ⊥=−770 MPa). These values are much higher than those measured at the ground surface geneRated using the sol–gel grinding wheel and cooling by liquid nitrogen (σ∥=−295 MPa, σ⊥=−250 MPa). Further, the CGTs and HSGTs results were used to establish the burn-free and burn conditions in relation with the specific grinding energy. It was shown that condition using the sol–gel grinding wheel and cooling with liquid nitrogen and condition using cBN grinding wheel at peripheral wheel speed up to 180 m/s geneRate specific grinding energy that are significantly lower than the burning threshold energy.
