Pub Date : 1999-01-01DOI: 10.1080/00202967.1999.11871236
S. Watson
{"title":"A Tale of Two Billion","authors":"S. Watson","doi":"10.1080/00202967.1999.11871236","DOIUrl":"https://doi.org/10.1080/00202967.1999.11871236","url":null,"abstract":"","PeriodicalId":23268,"journal":{"name":"Transactions of The Institute of Metal Finishing","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00202967.1999.11871236","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58741828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1999-01-01DOI: 10.1080/00202967.1999.11871271
Zelin Li, Jiale Cai, Shaomin Zhou
SUMMARYA new modelfor the anomalous codeposition of alloys is based on the kinetic characteristics of metal electrodeposition and the effect of hydrogen evolution accompanying the deposition. The less noble metal has intrinsically faster kinetics and so its deposition rate can be controlled mainly by diffusion mass transfer in a certain range of overpotentials; the convection induced by hydrogen evolution can speed up the relative deposition rate of this less noble metal when it is mainly diffusion-influenced. In contrast with previous models, such as the hydroxide suppression hypothesis, the monohydroxide-discharge-controlled mechanism, and the competitive adsorption effect, our model can explain naturally and completely anomalous codeposition, i.e. the preferential deposition of the less-noble metal, a problem in alloy electrodeposition that has persisted for a century.
{"title":"New insight into the anomalous codeposition of alloys","authors":"Zelin Li, Jiale Cai, Shaomin Zhou","doi":"10.1080/00202967.1999.11871271","DOIUrl":"https://doi.org/10.1080/00202967.1999.11871271","url":null,"abstract":"SUMMARYA new modelfor the anomalous codeposition of alloys is based on the kinetic characteristics of metal electrodeposition and the effect of hydrogen evolution accompanying the deposition. The less noble metal has intrinsically faster kinetics and so its deposition rate can be controlled mainly by diffusion mass transfer in a certain range of overpotentials; the convection induced by hydrogen evolution can speed up the relative deposition rate of this less noble metal when it is mainly diffusion-influenced. In contrast with previous models, such as the hydroxide suppression hypothesis, the monohydroxide-discharge-controlled mechanism, and the competitive adsorption effect, our model can explain naturally and completely anomalous codeposition, i.e. the preferential deposition of the less-noble metal, a problem in alloy electrodeposition that has persisted for a century.","PeriodicalId":23268,"journal":{"name":"Transactions of The Institute of Metal Finishing","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00202967.1999.11871271","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58742826","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1999-01-01DOI: 10.1080/00202967.1999.11871262
M. Mateescu, M. Preda, Stefan Ivascan
The quality of contact materials depends on their physical properties, such as density, hardness and conductivity, as well as on their contact characteristics (contact resistance, weldability and erosion). An instrumentation system is described here, which measures the most important attributes of contact materials simultaneously. The measurements are taken under simulated service conditions. The rated electrical current is passed through contacts of reference and test materials in a relay controlled by an electronic module; the contact resistance, weldability and are erosion are monitored. In this system two pairs of contact elements - one pair made of the test material, and the other made of reference material are compared. The relay is an actual electrical device wich would use the test material as its contact elements in normal operation. The test material is silver-cadmium alloy electrodeposited from an iodide bath; and the reference material is electrodeposited silver from a cyanide bath.
{"title":"Comparison of the switching behaviour of electrodeposited silver and silver-cadmium alloys contact materials","authors":"M. Mateescu, M. Preda, Stefan Ivascan","doi":"10.1080/00202967.1999.11871262","DOIUrl":"https://doi.org/10.1080/00202967.1999.11871262","url":null,"abstract":"The quality of contact materials depends on their physical properties, such as density, hardness and conductivity, as well as on their contact characteristics (contact resistance, weldability and erosion). An instrumentation system is described here, which measures the most important attributes of contact materials simultaneously. The measurements are taken under simulated service conditions. The rated electrical current is passed through contacts of reference and test materials in a relay controlled by an electronic module; the contact resistance, weldability and are erosion are monitored. In this system two pairs of contact elements - one pair made of the test material, and the other made of reference material are compared. The relay is an actual electrical device wich would use the test material as its contact elements in normal operation. The test material is silver-cadmium alloy electrodeposited from an iodide bath; and the reference material is electrodeposited silver from a cyanide bath.","PeriodicalId":23268,"journal":{"name":"Transactions of The Institute of Metal Finishing","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00202967.1999.11871262","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58742933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1999-01-01DOI: 10.1080/00202967.1999.11871283
S. Phadnis, A. Bose, M. Totlani
The electrochemical behaviour of zircaloy-2 in the annealed and quenched conditions was determined in 0.5 M H 2 SO 4 by the potentiodynamic polarization method. Passive films on zircaloy-2 obtained in air as well as in sulphuric acid under open circuit conditions, were characterised and their refractive index and thickness determined. It was seen that the beta quenched alloy showed a nobler potential (-270 mV against standard Calomel electrode) compared with the annealed alloy (-320 mV). It also showed a passive current density about one order less than the annealed material. Ellipsometry showed that the films formed on the quenched alloy were thinner than those on the annealed alloy. After exposure to 0.5 M H 2 SO 4 zircaloy developed films which were thicker with power refractive index than both the heat treated conditions. XPS analysis of the films has confirmed incorporation of sulphate into the film which probably leads to a defective and hence a thicker film in acid.
用动电位极化法测定了锆-2在0.5 M h2so4中退火和淬火条件下的电化学行为。在开路条件下，在空气和硫酸中制备了锆-2钝化膜，对其进行了表征，并测定了其折射率和厚度。与退火合金(-320 mV)相比，淬火合金表现出更高的电位(对标准甘汞电极为-270 mV)。它的无源电流密度也比退火后的材料小一个数量级。椭偏测量结果表明，淬火合金表面形成的薄膜比退火合金表面薄。暴露于0.5 M h2so4后，锆合金形成的薄膜比两种热处理条件下的薄膜更厚，其功率折射率也更高。薄膜的XPS分析证实了硫酸盐在薄膜中的掺入，这可能导致了缺陷，因此在酸中形成了较厚的薄膜。
{"title":"An ellipsometric, XPS and electrochemical study of the passivity of zircaloy-2","authors":"S. Phadnis, A. Bose, M. Totlani","doi":"10.1080/00202967.1999.11871283","DOIUrl":"https://doi.org/10.1080/00202967.1999.11871283","url":null,"abstract":"The electrochemical behaviour of zircaloy-2 in the annealed and quenched conditions was determined in 0.5 M H 2 SO 4 by the potentiodynamic polarization method. Passive films on zircaloy-2 obtained in air as well as in sulphuric acid under open circuit conditions, were characterised and their refractive index and thickness determined. It was seen that the beta quenched alloy showed a nobler potential (-270 mV against standard Calomel electrode) compared with the annealed alloy (-320 mV). It also showed a passive current density about one order less than the annealed material. Ellipsometry showed that the films formed on the quenched alloy were thinner than those on the annealed alloy. After exposure to 0.5 M H 2 SO 4 zircaloy developed films which were thicker with power refractive index than both the heat treated conditions. XPS analysis of the films has confirmed incorporation of sulphate into the film which probably leads to a defective and hence a thicker film in acid.","PeriodicalId":23268,"journal":{"name":"Transactions of The Institute of Metal Finishing","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00202967.1999.11871283","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58743085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1999-01-01DOI: 10.1080/00202967.1999.11871286
D. Gabe
The technique of Coulometry is based on the fundamental concepts incorporated in Faraday's Laws and is therefore a referee method for coating thickness determinations. The design of coulometric dissolution methods for thickness testing is reviewed. In the competitive field of modern instrumental techniques coulometry offers advantages of averaging thickness over an area typically of ∼1 cm 2 and the ability to measure components in a layered or duplex coating.
库仑法技术基于法拉第定律中的基本概念，因此是测定涂层厚度的一种裁判方法。综述了库仑溶出度测厚方法的设计。在现代仪器技术竞争激烈的领域中，库仑法具有在典型的~ 1 cm 2的面积上平均厚度的优势，并且能够测量层状或双相涂层中的成分。
{"title":"Coulometric Techniques for Surface Coatings","authors":"D. Gabe","doi":"10.1080/00202967.1999.11871286","DOIUrl":"https://doi.org/10.1080/00202967.1999.11871286","url":null,"abstract":"The technique of Coulometry is based on the fundamental concepts incorporated in Faraday's Laws and is therefore a referee method for coating thickness determinations. The design of coulometric dissolution methods for thickness testing is reviewed. In the competitive field of modern instrumental techniques coulometry offers advantages of averaging thickness over an area typically of ∼1 cm 2 and the ability to measure components in a layered or duplex coating.","PeriodicalId":23268,"journal":{"name":"Transactions of The Institute of Metal Finishing","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00202967.1999.11871286","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58743193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1999-01-01DOI: 10.1080/00202967.1999.11871253
J. Balaraju, S. Seshadri
SUMMARYThe present work pertains to the study of electroless Ni-P and Ni-P-Si3N4 composite coatings. The deposits are obtained from a proprietary high phosphorus electroless nickel plating bath, comprising nickel sulphate, sodium hypophosphite, complexing agents and stabilizers. The maximum weight percent of Si3N4 incorporated in the electroless deposit is obtained at a concentration of 10 g/l in the bath. The electroless Ni-P deposits having 0%, 2.01%, 5.81% and 8.10% of Si3N4, respectively, obtained from baths containing 0, 2, 5 and 10 g/l of Si3N4, are characterized by optical microscopy, XRD and TEM. Hardness is found to increase with the incorporation of Si3N4 at all heat treatment temperatures studied. Also hardness increases with an increase in weight percent of Si3N4 incorporated in the deposit. The analyses of the composite coatings by XRD and TEM reveal that the inclusion of Si3N4 particles does not change the amorphous nature of the Ni-P matrix.
{"title":"Preparation and Characterization of Electroless Ni-P and Ni-P-Si3N4 Composite Coatings","authors":"J. Balaraju, S. Seshadri","doi":"10.1080/00202967.1999.11871253","DOIUrl":"https://doi.org/10.1080/00202967.1999.11871253","url":null,"abstract":"SUMMARYThe present work pertains to the study of electroless Ni-P and Ni-P-Si3N4 composite coatings. The deposits are obtained from a proprietary high phosphorus electroless nickel plating bath, comprising nickel sulphate, sodium hypophosphite, complexing agents and stabilizers. The maximum weight percent of Si3N4 incorporated in the electroless deposit is obtained at a concentration of 10 g/l in the bath. The electroless Ni-P deposits having 0%, 2.01%, 5.81% and 8.10% of Si3N4, respectively, obtained from baths containing 0, 2, 5 and 10 g/l of Si3N4, are characterized by optical microscopy, XRD and TEM. Hardness is found to increase with the incorporation of Si3N4 at all heat treatment temperatures studied. Also hardness increases with an increase in weight percent of Si3N4 incorporated in the deposit. The analyses of the composite coatings by XRD and TEM reveal that the inclusion of Si3N4 particles does not change the amorphous nature of the Ni-P matrix.","PeriodicalId":23268,"journal":{"name":"Transactions of The Institute of Metal Finishing","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00202967.1999.11871253","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58742136","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1999-01-01DOI: 10.1080/00202967.1999.11871255
V. A. Zabludovsky, V. S. Gribok
A new electrolytic technology for obtaining Ni-Cu multi-layers by program-controlled pulse current is suggested The mechanical and electrical properties of the coatings were explored and experimental data were compared with theoretical.
{"title":"Physical properties of Ni-Cu microlayer films obtained by pulse electrolysis","authors":"V. A. Zabludovsky, V. S. Gribok","doi":"10.1080/00202967.1999.11871255","DOIUrl":"https://doi.org/10.1080/00202967.1999.11871255","url":null,"abstract":"A new electrolytic technology for obtaining Ni-Cu multi-layers by program-controlled pulse current is suggested The mechanical and electrical properties of the coatings were explored and experimental data were compared with theoretical.","PeriodicalId":23268,"journal":{"name":"Transactions of The Institute of Metal Finishing","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"1999-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00202967.1999.11871255","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58742391","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1998-01-01DOI: 10.1080/00202967.1998.11871201
S. Jayakrishnan, K. Dhayanand, R. Krishnan, R. Sekar, S. Sriveeraraghavan
SummaryElectroplating is a surface treatment method widely adopted for corrosion prevention. For obtaining decorative finishes with corrosion resistance on steel surfaces, it is a normal practice to employ decorative nickel—chromium plating consisting of thick nickel layers followed by flash chromium. For functional applications necessitating hardness and wear resistance, thick chromium plating is carried out either directly on steel or over a nickel undercoat. Heavy coatings of nickel and chromium for industrial applications call for thickness uniformity over complicated shaped basis metal surfaces.In the present investigation, a comparative evaluation of nickel and chromium plating is undertaken. Distributions of metal on plain as well as bent cathodes are determined. For a bent cathode with a specified geometry, the improvement in metal distribution brought about by changing the anode configuration is studied and reported.
{"title":"Metal distribution in electroplating of nickel and chromium","authors":"S. Jayakrishnan, K. Dhayanand, R. Krishnan, R. Sekar, S. Sriveeraraghavan","doi":"10.1080/00202967.1998.11871201","DOIUrl":"https://doi.org/10.1080/00202967.1998.11871201","url":null,"abstract":"SummaryElectroplating is a surface treatment method widely adopted for corrosion prevention. For obtaining decorative finishes with corrosion resistance on steel surfaces, it is a normal practice to employ decorative nickel—chromium plating consisting of thick nickel layers followed by flash chromium. For functional applications necessitating hardness and wear resistance, thick chromium plating is carried out either directly on steel or over a nickel undercoat. Heavy coatings of nickel and chromium for industrial applications call for thickness uniformity over complicated shaped basis metal surfaces.In the present investigation, a comparative evaluation of nickel and chromium plating is undertaken. Distributions of metal on plain as well as bent cathodes are determined. For a bent cathode with a specified geometry, the improvement in metal distribution brought about by changing the anode configuration is studied and reported.","PeriodicalId":23268,"journal":{"name":"Transactions of The Institute of Metal Finishing","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"1998-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00202967.1998.11871201","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58741158","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1998-01-01DOI: 10.1080/00202967.1998.11871223
G. Critchlow, K. Bedwell, C. Cottam
TEA CO 2 -laser ablation has been studied to establish its effectiveness for the cleaning of hot dipped galvanised (HDG) mild steel. This laser-based process was demonstrated to be more effective than double-degreasing for the removal of organic contamination from a previously oily surface. In addition, the TEA CO 2 -laser was shown to modify both the near surface chemistry and the topography; the precise modifications being dependent upon the degree of treatment used. In bond durability trials, the changes introduced to the laser-treated HDG surface were shown to provide equivalent or better joints compared with degreased adherends. In the same durability trials, a commercially-available phosphate-based, wet chemical treatment was shown to provide bond durability significantly inferior to the TEA CO 2 -laser. In contrast, a chromate-based process gave markedly superior bond durability. Possible explanations for the bond test results have been given.
{"title":"The Effectiveness of TEA CO2-laser Ablation for the Treatment of Hot Dipped Galvanized Mild Steel Prior to Adhesive Bonding","authors":"G. Critchlow, K. Bedwell, C. Cottam","doi":"10.1080/00202967.1998.11871223","DOIUrl":"https://doi.org/10.1080/00202967.1998.11871223","url":null,"abstract":"TEA CO 2 -laser ablation has been studied to establish its effectiveness for the cleaning of hot dipped galvanised (HDG) mild steel. This laser-based process was demonstrated to be more effective than double-degreasing for the removal of organic contamination from a previously oily surface. In addition, the TEA CO 2 -laser was shown to modify both the near surface chemistry and the topography; the precise modifications being dependent upon the degree of treatment used. In bond durability trials, the changes introduced to the laser-treated HDG surface were shown to provide equivalent or better joints compared with degreased adherends. In the same durability trials, a commercially-available phosphate-based, wet chemical treatment was shown to provide bond durability significantly inferior to the TEA CO 2 -laser. In contrast, a chromate-based process gave markedly superior bond durability. Possible explanations for the bond test results have been given.","PeriodicalId":23268,"journal":{"name":"Transactions of The Institute of Metal Finishing","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"1998-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00202967.1998.11871223","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58741293","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1998-01-01DOI: 10.1080/00202967.1998.11871184
O. Takai, T. Honjo
SummaryMicrowave plasma-enhanced CVD has been studied for the high rate coatings of silicon oxide using methyltrimethoxysilane, an organosilicon compound, and oxygen as gas sources. The transparent hard films could be deposited onto substrates at the high rate of about 1 μm/min. The composition of the films prepared at pressures below 100 Pa was similar to silicon dioxide. Analyses of the films were carried out by using XRD, FT-IR, XPS and AES.
{"title":"Microwave Plasma-Enhanced CVD for High Rate Coatings of Silicon Oxide","authors":"O. Takai, T. Honjo","doi":"10.1080/00202967.1998.11871184","DOIUrl":"https://doi.org/10.1080/00202967.1998.11871184","url":null,"abstract":"SummaryMicrowave plasma-enhanced CVD has been studied for the high rate coatings of silicon oxide using methyltrimethoxysilane, an organosilicon compound, and oxygen as gas sources. The transparent hard films could be deposited onto substrates at the high rate of about 1 μm/min. The composition of the films prepared at pressures below 100 Pa was similar to silicon dioxide. Analyses of the films were carried out by using XRD, FT-IR, XPS and AES.","PeriodicalId":23268,"journal":{"name":"Transactions of The Institute of Metal Finishing","volume":null,"pages":null},"PeriodicalIF":1.9,"publicationDate":"1998-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/00202967.1998.11871184","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"58740316","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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