... study, the properties of TiC and Ni3Al are for TiC, cci= 7.4 xlO'6/K, Ei= 320GPa, m= 0.1... more ... study, the properties of TiC and Ni3Al are for TiC, cci= 7.4 xlO'6/K, Ei= 320GPa, m= 0.195 for Ni3Al a2= 11.9 xl0" 6/K, E2= 199GPa, H2= 0.295 When a= 2.5 um, b= 3.0 um, t= 0.5 um andT=-1275K, substituting the upon data into equation (16) and solving, we find q=460.5 MPa. ...
Erbium oxide (Er2O3) coatings were deposited using filtered vacuum arc deposition (FVAD) and thei... more Erbium oxide (Er2O3) coatings were deposited using filtered vacuum arc deposition (FVAD) and their structure and thermal stability were studied as a function of fabrication parameters. The coatings were deposited on silicon wafer and tantalum substrates with an arc current of 50 A and a deposition rate of 1.6 ± 0.4 nm/s. The arc was sustained on truncated cone Er cathodes. The influence of oxygen pressure (P= 0.40-0.93 Pa), bias voltage (Vb=-20,-40 or grounded) and substrate temperature (room temperature (RT) or 673K) on film properties was studied before and after post deposition annealing (1273K for 1 hour, at P~ 1.33 Pa). The coatings were characterized using X-ray diffraction (XRD), optical microscopy, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and Knoop Hardness. Optical microscope images indicated that the coatings had very low macroparticle concentration on their surface. The macroparticle diameters were less than 2.5 μm. The coatings were composed of only Er2O3 without any metallic phase under all deposition parameters tested. The coatings deposited on RT substrates were XRD amorphous and had a featureless cross-section microstructure. However, the coatings deposited on 673K heated substrates had a C-Er2O3 structure with (222) preferred orientation and weak columnar microstructure. The coating hardness varied with deposition pressure and substrate bias, and reached a maximum value of 10 GPa at P = 0.4 Pa and Vb =-40 V. The post-deposition annealing caused crystallization, and the coatings hardness dropped to 4 GPa with thermal treatment. However, after postdeposition annealing, no peeling or cracking appeared at the coating surface or the interface with the substrate.
Ternary zirconia-alumina coatings with different compositional ratios, ranging from pure zirconia... more Ternary zirconia-alumina coatings with different compositional ratios, ranging from pure zirconia to 50% alumina content, were deposited by reactive sputtering from two targets, Zr and Al, in argon-oxygen mixtures. The coating composition was controlled by the Zr/Al target power ratio provided by two pulsed-DC power supplies. The coatings were ~1 m thick and they were deposited on floating potential substrates at a temperature of 650±3K. XRD indicated that the pure zirconia coatings possessed a monoclinic structure with a grain size of 35-40 nm. Adding alumina to the zirconia coating stabilized the cubic zirconia phase and decreased the grain size to 10-15 nm. The alumina phase in the coatings remained amorphous. The hardness of the nanocomposite structure increased from 11.6±0.5 GPa to 16.1±0.5 GPa for an alumina content of 17%. At higher alumina concentrations, the zirconia phase became amorphous and the hardness decreased to 10-11 GPa. Structure stability of the zirconia-alumina coatings was studied by measuring the coating structure and hardness after annealing at temperatures up to 1173 K. Pure zirconia (m-ZrO2) coatings had low structure stability; the hardness reached a maximum value of 18±1 GPa after annealing at a temperature of 773-873K; however, at higher annealing temperatures the hardness decreased, reaching a minimum value of 12.3±0.6 GPa after annealing at 1173K. The hardness of the nanocomposite ZrO2/Al2O3 coating with various compositions increased with annealing temperature. The hardness of a coating with an alumina content of 17% reached a high value of 19.2±0.5 GPa after annealing at 1073-1173 K. Measurements of post annealing XRD analyses indicated that the stabilization of the coating structure with c-ZrO2/a-Al2O3 phases is the reason for the higher structure stability. From the analyses of phase stability and hardness before and after annealing, we conclude that adding alumina to the zirconia phase promotes the formation of nanocomposite c-ZrO2/a-Al2O3 coatings with a markedly higher stability than single-phase m-ZrO2. Highlights: 1. ZrO2/Al2O3 nanocomposite coatings were deposited by co-sputtering from Zr and Al targets. 2. Adding alumina to the zirconia coating stabilized the cubic zirconia phase. 3. ZrO2-17% Al2O3 coatings had a grain size of 10-15 nm and a hardness of 16.1±0.5 GPa. 4. ZrO2/Al2O3 coatings maintained a high hardness after annealing at 1173K with a high value of 19 GPa for alumina content of 17%. 5. The ZrO2/Al2O3 nanocomposite coatings were crack-free after annealing at 1173K.
La nitruration d'alliages de titane Ti6Al4V a ete realisee dans un plasma rf d'azote, d&#... more La nitruration d'alliages de titane Ti6Al4V a ete realisee dans un plasma rf d'azote, d'hydrogene et d'argon avec une temperature de substrat de 500˚C. La microstructure et la composition des couches nitrurees obtenues ont ete etudiees par diffraction des RX, microscopie electronique a balayage et microscopie electronique en transmission. Les resultats obtenus sont discutes en relation avec la composition du gaz dans le plasma.
Erbium oxide (Er 2 O 3 ) coatings were deposited using filtered vacuum arc deposition (FVAD) and ... more Erbium oxide (Er 2 O 3 ) coatings were deposited using filtered vacuum arc deposition (FVAD) and their structure and thermal stability were studied as a function of fabrication parameters. The coatings were deposited on silicon wafer and tantalum substrates with an arc current of 50 A and a deposition rate of 1.6 ± 0.4 nm/s. The arc was sustained on truncated cone Er cathodes. The influence of oxygen pressure ( P = 0.40-0.93 Pa), bias voltage ( V b = -20, -40 or grounded) and substrate temperature (room temperature (RT) or 673K) on film properties was studied before and after post deposition annealing (1273K for 1 hour, at P ~ 1.33 Pa). The coatings were characterized using X-ray diffraction (XRD), optical microscopy, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and Knoop Hardness. Optical microscope images indicated that the coatings had very low macroparticle concentration on their surface. The macroparticle diameters were less than 2.5 I¼m. The coat...
A full-scale 300 m3/day industrial waste treatment system was put into operation in a petrochemic... more A full-scale 300 m3/day industrial waste treatment system was put into operation in a petrochemical manufacturing plant in Israel for the purpose of detoxifying its complex organic waste stream. The GPI treatment plant design incorporates an innovative waste management approach to accommodate the limited space allocated for the facility. It employs influent equalization and waste minimization techniques, in support of an advanced biophysical treatment process to accomplish a substantial reduction in the facility footprint while producing a high quality effluent. Initial performance data indicate a highly efficient organic waste reduction. COD and BOD removal surpassed 95% and 98%, respectively, over the initial two months of operation, meeting the stringent effluent discharge criteria. The system also provides effective sludge dewatering, producing 40-50% solids sludge, thereby minimizing sludge disposal costs.
Abstract Coating architectures with a microstructure controlled on nanoscale enables the attainme... more Abstract Coating architectures with a microstructure controlled on nanoscale enables the attainment of enhanced mechanical, tribological and other properties. In the present study, we fabricated nanolaminate ZrN/TiN systems with various modulation periods, L, ranging from 1 to 100 nm using pulsed DC magnetron sputtering. It was observed that a modulation period of L = 10 nm is a threshold value for the transition from a periodic to a solid solution structure. We demonstrate that the coatings with L
Ti-6Al-4V alloy has been nitrided in plasmas of N2 -H2 -Ar. The structure has been characterized ... more Ti-6Al-4V alloy has been nitrided in plasmas of N2 -H2 -Ar. The structure has been characterized by X-ray diffraction (XRD) for the determination of the products formed. The information was supported by elemental analysis with Auger Electron Spectroscopy (AES).Three phases were identified as follows: δ-TiN, ε-Ti2N and α'-Ti (solid solution of nitrogen in titanium). The gas-feed composition affects the nitriding process as found from phase orientation and relative concentration of the products.
... study, the properties of TiC and Ni3Al are for TiC, cci= 7.4 xlO'6/K, Ei= 320GPa, m= 0.1... more ... study, the properties of TiC and Ni3Al are for TiC, cci= 7.4 xlO'6/K, Ei= 320GPa, m= 0.195 for Ni3Al a2= 11.9 xl0" 6/K, E2= 199GPa, H2= 0.295 When a= 2.5 um, b= 3.0 um, t= 0.5 um andT=-1275K, substituting the upon data into equation (16) and solving, we find q=460.5 MPa. ...
... study, the properties of TiC and Ni3Al are for TiC, cci= 7.4 xlO'6/K, Ei= 320GPa, m= 0.1... more ... study, the properties of TiC and Ni3Al are for TiC, cci= 7.4 xlO'6/K, Ei= 320GPa, m= 0.195 for Ni3Al a2= 11.9 xl0" 6/K, E2= 199GPa, H2= 0.295 When a= 2.5 um, b= 3.0 um, t= 0.5 um andT=-1275K, substituting the upon data into equation (16) and solving, we find q=460.5 MPa. ...
Erbium oxide (Er2O3) coatings were deposited using filtered vacuum arc deposition (FVAD) and thei... more Erbium oxide (Er2O3) coatings were deposited using filtered vacuum arc deposition (FVAD) and their structure and thermal stability were studied as a function of fabrication parameters. The coatings were deposited on silicon wafer and tantalum substrates with an arc current of 50 A and a deposition rate of 1.6 ± 0.4 nm/s. The arc was sustained on truncated cone Er cathodes. The influence of oxygen pressure (P= 0.40-0.93 Pa), bias voltage (Vb=-20,-40 or grounded) and substrate temperature (room temperature (RT) or 673K) on film properties was studied before and after post deposition annealing (1273K for 1 hour, at P~ 1.33 Pa). The coatings were characterized using X-ray diffraction (XRD), optical microscopy, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and Knoop Hardness. Optical microscope images indicated that the coatings had very low macroparticle concentration on their surface. The macroparticle diameters were less than 2.5 μm. The coatings were composed of only Er2O3 without any metallic phase under all deposition parameters tested. The coatings deposited on RT substrates were XRD amorphous and had a featureless cross-section microstructure. However, the coatings deposited on 673K heated substrates had a C-Er2O3 structure with (222) preferred orientation and weak columnar microstructure. The coating hardness varied with deposition pressure and substrate bias, and reached a maximum value of 10 GPa at P = 0.4 Pa and Vb =-40 V. The post-deposition annealing caused crystallization, and the coatings hardness dropped to 4 GPa with thermal treatment. However, after postdeposition annealing, no peeling or cracking appeared at the coating surface or the interface with the substrate.
Ternary zirconia-alumina coatings with different compositional ratios, ranging from pure zirconia... more Ternary zirconia-alumina coatings with different compositional ratios, ranging from pure zirconia to 50% alumina content, were deposited by reactive sputtering from two targets, Zr and Al, in argon-oxygen mixtures. The coating composition was controlled by the Zr/Al target power ratio provided by two pulsed-DC power supplies. The coatings were ~1 m thick and they were deposited on floating potential substrates at a temperature of 650±3K. XRD indicated that the pure zirconia coatings possessed a monoclinic structure with a grain size of 35-40 nm. Adding alumina to the zirconia coating stabilized the cubic zirconia phase and decreased the grain size to 10-15 nm. The alumina phase in the coatings remained amorphous. The hardness of the nanocomposite structure increased from 11.6±0.5 GPa to 16.1±0.5 GPa for an alumina content of 17%. At higher alumina concentrations, the zirconia phase became amorphous and the hardness decreased to 10-11 GPa. Structure stability of the zirconia-alumina coatings was studied by measuring the coating structure and hardness after annealing at temperatures up to 1173 K. Pure zirconia (m-ZrO2) coatings had low structure stability; the hardness reached a maximum value of 18±1 GPa after annealing at a temperature of 773-873K; however, at higher annealing temperatures the hardness decreased, reaching a minimum value of 12.3±0.6 GPa after annealing at 1173K. The hardness of the nanocomposite ZrO2/Al2O3 coating with various compositions increased with annealing temperature. The hardness of a coating with an alumina content of 17% reached a high value of 19.2±0.5 GPa after annealing at 1073-1173 K. Measurements of post annealing XRD analyses indicated that the stabilization of the coating structure with c-ZrO2/a-Al2O3 phases is the reason for the higher structure stability. From the analyses of phase stability and hardness before and after annealing, we conclude that adding alumina to the zirconia phase promotes the formation of nanocomposite c-ZrO2/a-Al2O3 coatings with a markedly higher stability than single-phase m-ZrO2. Highlights: 1. ZrO2/Al2O3 nanocomposite coatings were deposited by co-sputtering from Zr and Al targets. 2. Adding alumina to the zirconia coating stabilized the cubic zirconia phase. 3. ZrO2-17% Al2O3 coatings had a grain size of 10-15 nm and a hardness of 16.1±0.5 GPa. 4. ZrO2/Al2O3 coatings maintained a high hardness after annealing at 1173K with a high value of 19 GPa for alumina content of 17%. 5. The ZrO2/Al2O3 nanocomposite coatings were crack-free after annealing at 1173K.
La nitruration d'alliages de titane Ti6Al4V a ete realisee dans un plasma rf d'azote, d&#... more La nitruration d'alliages de titane Ti6Al4V a ete realisee dans un plasma rf d'azote, d'hydrogene et d'argon avec une temperature de substrat de 500˚C. La microstructure et la composition des couches nitrurees obtenues ont ete etudiees par diffraction des RX, microscopie electronique a balayage et microscopie electronique en transmission. Les resultats obtenus sont discutes en relation avec la composition du gaz dans le plasma.
Erbium oxide (Er 2 O 3 ) coatings were deposited using filtered vacuum arc deposition (FVAD) and ... more Erbium oxide (Er 2 O 3 ) coatings were deposited using filtered vacuum arc deposition (FVAD) and their structure and thermal stability were studied as a function of fabrication parameters. The coatings were deposited on silicon wafer and tantalum substrates with an arc current of 50 A and a deposition rate of 1.6 ± 0.4 nm/s. The arc was sustained on truncated cone Er cathodes. The influence of oxygen pressure ( P = 0.40-0.93 Pa), bias voltage ( V b = -20, -40 or grounded) and substrate temperature (room temperature (RT) or 673K) on film properties was studied before and after post deposition annealing (1273K for 1 hour, at P ~ 1.33 Pa). The coatings were characterized using X-ray diffraction (XRD), optical microscopy, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and Knoop Hardness. Optical microscope images indicated that the coatings had very low macroparticle concentration on their surface. The macroparticle diameters were less than 2.5 I¼m. The coat...
A full-scale 300 m3/day industrial waste treatment system was put into operation in a petrochemic... more A full-scale 300 m3/day industrial waste treatment system was put into operation in a petrochemical manufacturing plant in Israel for the purpose of detoxifying its complex organic waste stream. The GPI treatment plant design incorporates an innovative waste management approach to accommodate the limited space allocated for the facility. It employs influent equalization and waste minimization techniques, in support of an advanced biophysical treatment process to accomplish a substantial reduction in the facility footprint while producing a high quality effluent. Initial performance data indicate a highly efficient organic waste reduction. COD and BOD removal surpassed 95% and 98%, respectively, over the initial two months of operation, meeting the stringent effluent discharge criteria. The system also provides effective sludge dewatering, producing 40-50% solids sludge, thereby minimizing sludge disposal costs.
Abstract Coating architectures with a microstructure controlled on nanoscale enables the attainme... more Abstract Coating architectures with a microstructure controlled on nanoscale enables the attainment of enhanced mechanical, tribological and other properties. In the present study, we fabricated nanolaminate ZrN/TiN systems with various modulation periods, L, ranging from 1 to 100 nm using pulsed DC magnetron sputtering. It was observed that a modulation period of L = 10 nm is a threshold value for the transition from a periodic to a solid solution structure. We demonstrate that the coatings with L
Ti-6Al-4V alloy has been nitrided in plasmas of N2 -H2 -Ar. The structure has been characterized ... more Ti-6Al-4V alloy has been nitrided in plasmas of N2 -H2 -Ar. The structure has been characterized by X-ray diffraction (XRD) for the determination of the products formed. The information was supported by elemental analysis with Auger Electron Spectroscopy (AES).Three phases were identified as follows: δ-TiN, ε-Ti2N and α'-Ti (solid solution of nitrogen in titanium). The gas-feed composition affects the nitriding process as found from phase orientation and relative concentration of the products.
... study, the properties of TiC and Ni3Al are for TiC, cci= 7.4 xlO'6/K, Ei= 320GPa, m= 0.1... more ... study, the properties of TiC and Ni3Al are for TiC, cci= 7.4 xlO'6/K, Ei= 320GPa, m= 0.195 for Ni3Al a2= 11.9 xl0" 6/K, E2= 199GPa, H2= 0.295 When a= 2.5 um, b= 3.0 um, t= 0.5 um andT=-1275K, substituting the upon data into equation (16) and solving, we find q=460.5 MPa. ...
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