Materials Transactions Jim最新文献_第2页

Galvanic corrosion of dental amalgams in contact with titanium in terms of released ions : Biomaterials and bioengineering 牙汞合金与钛接触的电偶腐蚀释出离子:生物材料和生物工程

Materials Transactions Jim Pub Date : 2002-12-01 DOI: 10.2320/MATERTRANS.43.3146

Y. Takada, Shi-Duk Lim, K. Asami, K. Kim, O. Okuno

{"title":"Galvanic corrosion of dental amalgams in contact with titanium in terms of released ions : Biomaterials and bioengineering","authors":"Y. Takada, Shi-Duk Lim, K. Asami, K. Kim, O. Okuno","doi":"10.2320/MATERTRANS.43.3146","DOIUrl":"https://doi.org/10.2320/MATERTRANS.43.3146","url":null,"abstract":"Galvanic corrosion between dental amalgams and titanium was examined in terms of released ions. The ions released from the dental amalgams in contact with titanium at surface area ratios of titanium/amalgam in a range of 1/10-10/1 were quantitatively analyzed after being immersed in 0.9mass% sodium chloride solution at 310K for 6.05 x 10 5 s. The potentials and the anodic polarization curves were also measured under the same conditions. Furthermore, the amalgam surfaces after immersion were analyzed using WDS. Each potential of the conventional amalgams was always lower than that of titanium, though each potential of the high-copper amalgam was reversed in the early stage of immersion and was also lower. When the surface area ratio did not increase to over 1/1, each total amount of ions released from the amalgams in contact with titanium was a little larger or smaller than that released from amalgams not in contact with titanium. However, tin and copper ions released from the conventional amalgams and the high-copper amalgam, respectively, increased greatly when the ratio grew to 10/1. Each amount of released ions with titanium, except mercury ions, was approximated by the equation W with = a x (W without ) b , where the coefficients a and b are constant and W with and W without mean each amount of the released ions with and without titanium, respectively. The coefficient b probably relied on the surface area ratio and immersion time. When the ratio grew to 10/1, the amount of released ions with titanium, except mercury ions, could be shown by the equation W with = a x (W without ) at a = 4.202-9.982. Since the contact with titanium seemed to drastically make the amount of mercury ions decrease, the mercury ions did not fit this equation. These results indicated a risk of galvanic corrosion between dental amalgams and titanium with a large surface area ratio.","PeriodicalId":18264,"journal":{"name":"Materials Transactions Jim","volume":"11 1","pages":"3146-3154"},"PeriodicalIF":0.0,"publicationDate":"2002-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82591632","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Evaluation of the hydroxyapatite film coating on titanium cathode by QCM : Biomaterials and bioengineering 羟基磷灰石膜涂层在钛阴极上的QCM评价:生物材料与生物工程

Materials Transactions Jim Pub Date : 2002-12-01 DOI: 10.2320/MATERTRANS.43.3010

M. Okido, K. Nishikawa, K. Kuroda, R. Ichino, Zhongwei Zhao, O. Takai

{"title":"Evaluation of the hydroxyapatite film coating on titanium cathode by QCM : Biomaterials and bioengineering","authors":"M. Okido, K. Nishikawa, K. Kuroda, R. Ichino, Zhongwei Zhao, O. Takai","doi":"10.2320/MATERTRANS.43.3010","DOIUrl":"https://doi.org/10.2320/MATERTRANS.43.3010","url":null,"abstract":"A titanium substrate was coated with a hydroxyapatite (HA) film under a cathodic potential in aqueous solutions containing calcium and phosphate ions and hydrogen peroxide at pH 5.5 and a temperature of 309.5 K. The deposition process was monitored using the current density change, and the mass change was measured using the electrochemical quartz crystal microbalance (QCM) technique at cathodic potentials, and compared with deposition on a gold substrate. The deposits were analyzed using X-ray diffraction and scanning electron microscopy. HA films were obtained at different cathodic potentials, and the film morphology changed with the potential. With electrolysis at -557 mV, HA was deposited and accumulated after 800 s, when the mass gain increased significantly, as determined using QCM. After 800 s, the cathodic current increased and then decreased with HA growth. The HA film was porous, with pores several hundred nanometers in size, and formed a network of aggregates with walls about 50 nm thick. The filling factor was about 59 vol%, as evaluated from the mass gain using QCM and microscopic observation.","PeriodicalId":18264,"journal":{"name":"Materials Transactions Jim","volume":"5 1","pages":"3010-3014"},"PeriodicalIF":0.0,"publicationDate":"2002-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82552981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 22

Grain boundary character and superplasticity of fine-grained ultra-high carbon steel : Superplasticity and its applications 细晶超高碳钢的晶界特性与超塑性:超塑性及其应用

Materials Transactions Jim Pub Date : 2002-10-01 DOI: 10.2320/MATERTRANS.43.2455

T. Furuhara, E. Sato, T. Mizoguchi, Shuji Furimoto, T. Maki

{"title":"Grain boundary character and superplasticity of fine-grained ultra-high carbon steel : Superplasticity and its applications","authors":"T. Furuhara, E. Sato, T. Mizoguchi, Shuji Furimoto, T. Maki","doi":"10.2320/MATERTRANS.43.2455","DOIUrl":"https://doi.org/10.2320/MATERTRANS.43.2455","url":null,"abstract":"The characteristics and superplasticity of the (a + θ) microduplex structures formed by various thermomechanical processings were studied in an ultra-high carbon steel (Fe-1.4Cr-1.0C). After heavy warm rolling of pearlite, an (a + θ) microduplex structure with equi-axed a grains of 0.4 pm in diameter and spheroidized θ particles of 0.2 μm in diameter is obtained. The a matrix exhibits a recovered structure in which most of a grain boundaries are low-angle boundaries, resulting in rather smaller elongation at 973 K. Heavy cold rolling and annealing of pearlite produces an (a + θ) microduplex structure which consists of the coarse-grain region (d α ∼ 0.4 μm) with high-angle a boundaries and the fine-grain region (d α ∼ 0.2 μm) with low-angle a boundaries. Superplasticity in this specimen is slightly better than the warm-rolled specimen. When pearlite was austenitized in the (y + θ) region, quenched and tempered at the temperature below A 1 , an (a + θ) microduplex structure in which a and θ grain sizes are nearly the same as in the warm-rolled specimen and most of a boundaries are of high-angle one is formed. Such ultra-fine a grains are formed through the recovery of the fine (a' lath martensite + θ) mixture during tempering. This microduplex structure exhibits superior superplasticity. Heavy warm rolling prior to the quenching and tempering improves total elongation further because the distribution of prior y grain size is more uniform. When cold-rolled pearlite was austenitized and air-cooled, an (a + θ) microduplex structure with high-angle a boundary is formed. However, since the a grain size was relatively large (ca. 2 μm), its superplastic performance is poor. Finally, more simplification of processing for superplasticity was attempted. Further improvement of superplasticity was achieved by omitting the tempering in the quenching and tempering treatment.","PeriodicalId":18264,"journal":{"name":"Materials Transactions Jim","volume":"16 1","pages":"2455-2462"},"PeriodicalIF":0.0,"publicationDate":"2002-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74470570","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 12

Martensitic Transformations : Microstructures and Uniaxial Stress, Magnetic Field and Hydrostatic Pressure Effects 马氏体相变:微观结构和单轴应力、磁场和静水压力效应

Materials Transactions Jim Pub Date : 2002-08-01 DOI: 10.2320/MATERTRANS.43.2050

K. Shimizu

引用次数: 4

Role of electrode potential difference between lead-free solder and copper base metal in wetting : Lead-free electronics packaging 无铅焊料和铜基体金属在润湿过程中电极电位差的作用:无铅电子封装

Materials Transactions Jim Pub Date : 2002-08-01 DOI: 10.2320/MATERTRANS.43.1784

T. Takemoto, Tatsuya Funaki

{"title":"Role of electrode potential difference between lead-free solder and copper base metal in wetting : Lead-free electronics packaging","authors":"T. Takemoto, Tatsuya Funaki","doi":"10.2320/MATERTRANS.43.1784","DOIUrl":"https://doi.org/10.2320/MATERTRANS.43.1784","url":null,"abstract":"The role of the electrochemical reaction between solder and copper base metal in soldering flux was investigated in relation to wetting. The research includes the contact polarization between solder and base metal in soldering flux of RA type. The difference of electrode potential between solder and base metal in soldering flux plays an important role in removing the oxide film by contact polarization. It is concluded that the electrode potential of Sn-based lead-free solders should be significantly lower than copper to obtain good wettability, because the accelerated anodic dissolution of tin by contacting with the copper base metal enhances the wettability by the removal of tin oxide which is one of the stable oxide on base metal and solder. Sn-Pb has the adequate electrode potential to be effectively dissolved when contacted by copper. On the other hand, the electrode potential of Sn-3.5Ag is very close to copper: the condition gives extremely small contact current. The addition of less noble elements that can lower the electrode potential is effective to enhance the wettability of Sn-3.5Ag. Sn-Zn solder has extremely low electrode potential than a copper base metal; the situation excessively accelerates the preferential anodic dissolution of zinc resulting in the no dissolution of tin. The addition of lead to Sn-3.5Ag solder lowered the electrode potential, which increased the potential difference between solder and copper base metal, as a result the contact current between them was increased. The improved wettability is confirmed by adding lead to Sn-3.5Ag; all lead added solders showed a larger spread area, i.e., a smaller contact angle than Sn-3.5Ag after the spreading test. This work proposed the role of electrochemistry in wetting based on the potential difference between base metal and solder including the degree of contact corrosion current between them.","PeriodicalId":18264,"journal":{"name":"Materials Transactions Jim","volume":"74 1","pages":"1784-1790"},"PeriodicalIF":0.0,"publicationDate":"2002-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85895977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 36

Determination of atomic sites of Nb dissolved in metastable Fe23B6 phase : Bulk amorphous, nano-crystalline and nano-quasicrystalline alloys IV 铌在亚稳Fe23B6相中原子位置的测定:大块非晶、纳米晶和纳米准晶合金IV

Materials Transactions Jim Pub Date : 2002-08-01 DOI: 10.2320/MATERTRANS.43.1918

Takahiro Nakamura, H. Koshiba, M. Imafuku, A. Inoue, E. Matsubara

引用次数: 15

Effect of annealing atmosphere on void formation in copper interconnects : Special issue on materials-related issues for Cu interconnects used in ultra high speed large scaled integrated Si devices 退火气氛对铜互连中空洞形成的影响:超高速大型集成硅器件用铜互连材料相关问题特刊

Materials Transactions Jim Pub Date : 2002-07-01 DOI: 10.2320/MATERTRANS.43.1624

S. Konishi, M. Moriyama, M. Murakami

引用次数: 14

Recovery of hydrogen induced defects and thermal desorption of residual hydrogen in LaNi5 : Special issue on grain boundaries, interfaces, defects and localized quantum structures in ceramics LaNi5中氢致缺陷的恢复和残余氢的热解吸:陶瓷中的晶界、界面、缺陷和局域量子结构专刊

Materials Transactions Jim Pub Date : 2002-07-01 DOI: 10.2320/MATERTRANS.43.1494

K. Sakaki, H. Araki, Y. Shirai

引用次数: 20

Theoretical formation energy of oxygen-vacancies in oxides : Special issue on grain boundaries, interfaces, defects and localized quantum structures in ceramics 氧化物中氧空位的理论形成能:陶瓷的晶界、界面、缺陷和局域量子结构专刊

Materials Transactions Jim Pub Date : 2002-07-01 DOI: 10.2320/MATERTRANS.43.1426

I. Tanaka, F. Oba, K. Tatsumi, M. Kunisu, M. Nakano, H. Adachi

引用次数: 99

Copper wires for high speed logic LSI prepared by low pressure long throw sputtering method : Special issue on materials-related issues for Cu interconnects used in ultra high speed large scaled integrated Si devices 低压长溅射法制备高速逻辑LSI用铜线:超高速大规模集成硅器件用铜互连材料相关问题专刊

Materials Transactions Jim Pub Date : 2002-07-01 DOI: 10.2320/MATERTRANS.43.1599

T. Saito, T. Hashimoto, N. Ohashi, T. Fujiwara, H. Yamaguchi

引用次数: 3