著者

釘屋 奈都子 永田 和宏 北田 正弘

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.78, no.4, pp.149-158, 2014 (Released:2014-04-01)

参考文献数

14

被引用文献数

1 4

---

The manufacturing technique of steel chains used for four Japanese armatures from the end of Muromachi to the Edo period has been investigated. The chains used in Kusazuri (tasset) and two types of Kote (guntlet) were composed of steel rings in round and oval shapes while those used in Kusarikatabira (chainmail) was only round. As for the former ones, round rings were connected by oval rings. The diameter of steel wire of rings was about 1 mm. The steel wire was produced from steel plate with the carbon content of 0.11 to 0.40 mass%. Steel was forge-and-welded twice to make in plate and was cut in a bar. The steel bar was drawn into standardized wires by die with the draft percentage of about 25% and annealed. Drawing of standardized wire followed by annealing was repeated several times to make a wire for armatures. The crystal grains in wires were elongated in axial direction and the aspect ratio of grain in oval rings was larger than that in round rings. A wire was rolled around a stick and cut by chisel to make rings.

著者

杉岡 奈穂子 北田 正弘 西嶋 雅彦

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.77, no.5, pp.185-191, 2013 (Released:2013-05-01)

参考文献数

15

被引用文献数

2

---

The metallurgical microstructure and mechanical properties of the spear blade manufactured in the Edo period have been investigated. The purpose of this work is to obtain metallographic data of the spear blade, and to clarify the manufacturing technique of the spear blade. The specimen examined was estimated to have been made from the end of the Muromachi period to the Edo period and has the signature of Shinano-no-Kami Minamoto Takamichi. The spear is 31 cm in length and 10.7 mm in maximum width. The metallurgical microstructure and nonmetallic inclusions of the spear blade are observed using an optical microscope. The carbon concentration is determined by chemical analysis. To evaluate the hardness, micro Vickers hardness (Hmv) is used. The microstructure is observed using an optical microscope and a scanning electron microscope (SEM). The concentration of nonmetallic inclusions is obtained by electron dispersive X-ray analysis (EDS).    A cross-sectional image of the spear after chemical etching shows a metal flow pattern formed by deformation, possibly created by hammering. The striped structure of layers of two types of steel containing different carbon contents stacked on top of each other was observed. The bright areas after etching corresponded to the edges and ridges of the spear, which were cooled rapidly, forming the martensite structure. The other dark areas consist of pearlite and α-Fe (ferrite) grains. Optical micrographs of near-edge areas contain pearlite and martensite grains, and core areas contain pearlite and α-Fe grains. The nonmetallic inclusions in the core steel consist of a few metal oxide particles and a glass matrix. There are Fe-Ti oxide grains in the glass matrix, and an unknown oxide particle adhering on the Fe-Ti oxide grain surface was also observed.

著者

北田正弘著

出版者

雄山閣

巻号頁・発行日

2017

著者

星 恵理子 北田 正弘

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.67, no.7, pp.336-341, 2003 (Released:2008-04-24)

参考文献数

12

被引用文献数

4

---

The effects of Cu-containing pigments on degradation of Japanese paper have been investigated. A hand-coloured wood-block print of the late Edo era is used as a naturally aged specimen. To clarify the degradation mechanism, sheets of modern Japanese paper painted with powdered malachite are aged in an environment of 353.15 K(80°C), 65%RH. Pigments are examined with XRD. Degradation of the paper is examined with a three-dimensional fluorescence spectrometer. Cu content in the specimen is measured by ICP-AES and EDS. The Cu concentrations of the cross-sections of naturally aged specimen decrease with increasing depth. In addition, the Cu concentrations at the same depth of the artificially aged paper increase with aging. These results show that the Cu species diffuse from the right to the wrong side of the paper. Although the green pigment of wood-block print contains Cu species and As species, only the Cu species has been detected in the fiber of the degraded part of the paper. The degree of degradation of the accelerated sample painted with malachite becomes higher than that of the unpainted sample. Therefore Cu is the main species that participates in the degradation of paper. The fluorescence intensity of the papers painted with malachite decreased with increasing aging time. This result shows that diffused Cu ions make impurity levels in the band gap of cellulose.

著者

北田 正弘

出版者

東京芸術大学

雑誌

基盤研究(B)

巻号頁・発行日

2006

---

日本刀はわが国が世界に誇る鉄鋼の文化財である。その美術的な価値はもちろんのこと、手作りに近い技術水準の時代に、非常に高品質の鋼を生産し、異なる鋼種を使い分け、加工・熱処理技術も高い水準に達していたとみられる。大量生産には適する技術ではなかったが、その技術には現代でも学ぶべきものがあると考えられ、先端科学的な研究が必要である。しかし、日本刀に関する現代の材料科学水準での研究は全く行われておらず、その評価内容は伝承と鑑賞面だけのものであった。そこで、日本刀の材料科学的評価に着手し、鋼の微細構造、非金属介在物の微細構造、機械的性質、化学的性質などを総合的に検討してきたが、その結果の中に工業的に得られる平均結晶粒径(25~30μm)より小さいものが見出された。これが日本刀における標準的なものなのか、あるいは見出された刀だけのものなのかを判断するには、ある程度の数の日本刀を調べなければならない。そこで、鎌倉時代から江戸時代末期までに造られた日本刀の微細組織を調べ、日本刀における微細結晶粒の状況と、これらの結果から導かれる微細結晶粒の生成機構について追及した。その結果、鎌倉時代から室町時代末までに製作された日本刀には、平均結晶粒径が10~20μmのものが多く観察され、最も小さいものでは数μmの結晶粒径をもつ日本刀が観察された。しかし、江戸時代の刀では結晶粒径の小さいものは少なく、時代によって変遷のあることが明らかになった。最も結晶粒径の小さい日本刀は室町中期頃に製造されたものである。ただし、統計的に時代の変遷あるいは特徴を把握するだけの数の試料は分析していないので、上述の時代依存性は実験の範囲内に限った傾向である。微細結晶粒は刃に使われている鋼および刃と芯金の境界領域で観察される。刃の非金属介在物を観察すると、結晶粒径の小さいものほど非金属介在物が小さい傾向を示す。これは、鋼の鍛錬の回数が多いことを示し、鍛錬加工と結晶粒度に深い関係があることを示す。また、非金属介在物の微細構造を観察すると、芯金の非金属介在物が融解して複雑な構造を示すのにたいし、刃金の非金属介在物は比較的単純な構造を示し、かつ、破壊された形状を示すものが多い。これは、刃の部分の加熱温度が低いことを示唆するものと考えられる。実際の加熱方法は不明であるが、比較的低い温度で熱間の鍛錬が行われ、導入された転位等の欠陥による再結晶が生じても、低温のため結晶粒成長が少なく、小さな結晶寸法を保っているものと考えられる。また、鍛錬の回数が多いため、蓄積されるひずみエネルギーが大きく、再結晶における結晶核の生成数が多く、結晶粒の微細化を促しているものと推定される。また、刃金と芯金の境界に微細な結晶粒が存在するものもある。刃金の炭素濃度は平均で約0.6mass%の中炭素鋼であり、芯金の炭素濃度は0.1mass%以下の低炭素鋼である。刃金と芯金は鍛接されるが、加工熱処理の段階で炭素の拡散が生じ、これと同時に加工によるひずみが導入される。これが再結晶の核形成頻度を増大させているものと考えられる。定量的データーを得る段階には達していないが、これらの結果は、微細結晶粒を鋼に付与する方法として有効な成果と考えられる。

著者

高林 弘実 北田 正弘 辻本 勝浩

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.69, no.7, pp.538-543, 2005 (Released:2005-10-12)

参考文献数

17

被引用文献数

3 3

---

The discoloration and chemical composition changes of red-lead used for wood-block print made in the late Edo period have been investigated. Both the chromaticity and lightness of red-lead decrease with discoloration, and its hue exhibits very little change. This is due to the reflectance decrease of red-lead in a long-wavelength range beyond the absorption edge of 580 nm. Red-lead is a mixture of Pb3O4 and β-PbO and has a grain size of 0.05-0.2 μm. The X-ray diffraction intensity of β-PbO considerably decreases with discoloration in comparison with that from Pb3O4. This result shows that β-PbO is more reactive than Pb3O4 in the mixture. The results of XPS measurement suggest that both lead chloride and lead carbonate exist in the surface layer of red-lead.

著者

北田 正弘 桐野 文良

出版者

公益社団法人 日本表面科学会

雑誌

表面科学 (ISSN:03885321)

巻号頁・発行日

vol.26, no.4, pp.226-230, 2005-04-10 (Released:2007-12-21)

参考文献数

7

被引用文献数

1

---

Traditional coloring techniques used in Japanese metal crafts, such as niiro and iroage, are explained. In niiro for copper-gold alloys, a Cu2O layer in which gold particles are dispersed is formed on the alloy surface. This gold alloy is colored through absorption and reflection of light by gold particles in the layer. Besides coloring, this layer functions to prevent corrosion. In iroage for gold-silver alloys, silver dissolves selectively by heating after a chemical is applied on the metal surface. As a gold-rich layer is formed on the gold-silver alloy surface, the gold color is produced.

著者

田中 眞奈子 北田 正弘

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.74, no.4, pp.250-257, 2010 (Released:2010-04-01)

参考文献数

16

被引用文献数

7 5

---

The composition and microstructure of nonmetallic inclusions of a Japanese matchlock gun, called Hinawa-ju in Japanese, fabricated in the Edo period have been investigated. The purpose of this work is to study the composition and microstructure of nonmetallic inclusions of the barrel and to obtain modern materials-science data of the raw materials of the Japanese matchlock gun. Test pieces are cut from the center and the male screw of the barrel. Nonmetallic inclusions of the barrel are observed using an optical microscope and scanning electron microscope (SEM). The small-area concentration of a nonmetallic inclusion is obtained by electron dispersive X-ray analysis (EDS). The electron backscattering pattern (EBSP) is analyzed using an ultrahigh-resolution scanning electron microscope. Fe, Si, Al, Ca, K, Mg, P, Na and Ti are detected from nonmetallic inclusions of the center of the barrel. As Ti is detected from many parts of the nonmetallic inclusions, iron sand is inferred to have been used as the raw iron material of the barrel. Nonmetallic inclusions of the center of the barrel are classified into two groups. One is a plural phase and is consisted of FeO (wustite), Fe-Si-O grains, multi-element grains and glass-rich matrix oxide. The other type is a single phase of aluminum silicate glass. Fe, Si, Al, Ti, Ca, Mg, K, Na, P, Mn and S are detected from nonmetallic inclusions of the male screw of the barrel. As Ti is detected from many parts of the nonmetallic inclusions, iron sand is again thought to have been used as the raw iron material of the male screw. Nonmetallic inclusions of the male screw are of the plural phase and consist of Fe-Ti-O grains, aluminum silicate oxide and aluminum silicate glass matrix.

著者

田中 眞奈子 北田 正弘

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.76, no.8, pp.489-495, 2012 (Released:2012-08-01)

参考文献数

15

被引用文献数

2 1

---

The microstructure and mechanical properties of the steel barrel of a Japanese matchlock gun fabricated by the gunsmith Kunitomo Tokudayuu in the Edo Genroku period have been investigated. The purpose of this work is to obtain modern materials-science data for a Japanese matchlock gun fabricated by a noted Kunitomo gunsmith and to study the manufacturing technique of the steel barrel. Specimens are cut from the center, the muzzle, and the screw of the barrel. The carbon concentration is determined by chemical analysis. The microstructure and nonmetallic inclusions of the specimens are observed with an optical microscope and a scanning electron microscope (SEM). To evaluate the hardness, Vickers hardness (Hv) is used. The inner structure of the screw is observed by X-ray radiography. The carbon concentration is 0.007 mass% in the center of the barrel and 0.07-0.3 mass% in the muzzle. The distribution of nonmetallic inclusions in the center of the barrel indicates that the barrel was fabricated by joining two long edges of a steel sheet, a technique that is called Udonbari (seamed steel pipe in Japanese). The muzzle was reinforced with steel having a higher carbon content than that of the center of the barrel by rolling the steel over the Udonbari barrel. The female screw of the barrel was made of clad steel. Both male and female screws of the barrel were made by a cutting technique.

著者

貴田 啓子 北田 正弘

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.74, no.3, pp.158-164, 2010 (Released:2010-03-01)

参考文献数

8

被引用文献数

11 7

---

The deterioration mechanism of ferric ferrocyanide (Fe4[Fe(CN)6]3·xH2O) which is called Prussian blue, used as a blue pigment in Ukiyo-e printed in late Edo period, has been investigated. The two Ukiyo-e of the same design differ in their degree of deterioration; one print has good color, but the other is seriously discolored. The conditions of their blue areas are compared. The composition of the Ukiyo-e color pigments are analyzed by EDS (Energy Dispersive X-ray Spectroscopy). FT-IR (Fourier Transform infrared Spectrometer) is used to identify the functional group in the chemical compound. Areas of good blue color in the Ukiyo-e contain Fe, which is the main element in ferric ferrocyanide. In the FT-IR spectra, the absorption peak of around 2090 cm-1 corresponding to the CN triplet combination of ferric ferrocyanide (Fe4[Fe(CN)6]3·xH2O) is recognized. The Fe concentration in the faded blue area in the discolored sample is reduced to one-third that in the nondiscolored sample at the same position. The peak corresponding to the CN group has disappeared. A non discolored sample is subjected to accelerated ageing under the condition of high temperature and high humidity (353 K, 65%rh). The peak intensity of reflectivity in the aged sample decreases gradually with ageing.

著者

北田 正弘 桐野 文良 山本 和弘

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.71, no.1, pp.85-89, 2007 (Released:2007-01-01)

参考文献数

22

---

The surface structure of a metallic mirror fabricated in the late Edo period has been investigated. A Sn layer of 100 nm thickness on the mirror surface is observed by cross-sectional Transmission electron microscopy (TEM). Hg is detected in the Sn layer by EDX analysis. This means that the surface Sn layer of the mirror was fabricated using an Hg-amalgam technique. By AES measurement, an Sn-Cu alloy at the interface between the Sn layer and the Cu base metal is detected. The Sn surface has been oxidized. The oxide layer consists of SnO2, SnO•SnO2, SnO and Sn in order of increasing distance from the surface.

著者

田中 眞奈子 北田 正弘

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.73, no.10, pp.778-785, 2009 (Released:2009-10-01)

参考文献数

10

被引用文献数

5 6

---

The metallurgical microstructure and mechanical properties of the steel barrel of a Japanese matchlock gun fabricated in the Edo period have been investigated. The purpose of this work is to obtain modern materials-science data of the Japanese matchlock gun and to study the manufacturing technique of the steel barrel. Test pieces are cut from the center, the muzzle and the screw of the barrel. The carbon concentration is determined by chemical analysis. The metallurgical microstructure and nonmetallic inclusions of the barrel are observed using an optical microscope and a scanning electron microscope (SEM). Test pieces for measuring the mechanical properties are cut from the gun. To evaluate the hardness, Vickers hardness (Hv) is used. The stress-strain curve, tensile strength and elongation of the gun are obtained.    The carbon concentration is 0.01∼0.1mass% for the center of the barrel, 0.04∼0.1 mass% for the muzzle of the barrel, 0.05∼0.5 mass% for the front sight (Saki-meate in Japanese) and 0.13∼0.3 mass% for the male screw. The distribution of nonmetallic inclusions in the center and in the muzzle of the barrel suggest that the barrel was fabricated by a manufacturing technique called Udonbari (in Japanese). The metallurgical microstructure of the specimen taken from the muzzle of the barrel in the vertical direction suggests that the barrel and a front sight were joined mechanically. Both male and female screws were made by a cutting technique. The tensile strength and elongation are 316∼366 MPa and 25.0∼31.4%, respectively.

著者

杉岡 奈穂子 北田 正弘 西嶋 雅彦

出版者

公益社団法人 日本金属学会

雑誌

日本金屬學會誌 (ISSN:00214876)

巻号頁・発行日

vol.77, no.5, pp.185-191, 2013-05-01

参考文献数

15

被引用文献数

2

---

&nbsp;&nbsp;The metallurgical microstructure and mechanical properties of the spear blade manufactured in the Edo period have been investigated. The purpose of this work is to obtain metallographic data of the spear blade, and to clarify the manufacturing technique of the spear blade. The specimen examined was estimated to have been made from the end of the Muromachi period to the Edo period and has the signature of <i>Shinano-no-Kami Minamoto Takamichi</i>. The spear is 31 cm in length and 10.7 mm in maximum width. The metallurgical microstructure and nonmetallic inclusions of the spear blade are observed using an optical microscope. The carbon concentration is determined by chemical analysis. To evaluate the hardness, micro Vickers hardness (<i>H</i>_mv) is used. The microstructure is observed using an optical microscope and a scanning electron microscope (SEM). The concentration of nonmetallic inclusions is obtained by electron dispersive X-ray analysis (EDS).<br> &nbsp;&nbsp; A cross-sectional image of the spear after chemical etching shows a metal flow pattern formed by deformation, possibly created by hammering. The striped structure of layers of two types of steel containing different carbon contents stacked on top of each other was observed. The bright areas after etching corresponded to the edges and ridges of the spear, which were cooled rapidly, forming the martensite structure. The other dark areas consist of pearlite and &alpha;-Fe (ferrite) grains. Optical micrographs of near-edge areas contain pearlite and martensite grains, and core areas contain pearlite and &alpha;-Fe grains. The nonmetallic inclusions in the core steel consist of a few metal oxide particles and a glass matrix. There are Fe-Ti oxide grains in the glass matrix, and an unknown oxide particle adhering on the Fe-Ti oxide grain surface was also observed.<br>

著者

桐野 文良 北田 正弘

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.79, no.2, pp.57-63, 2015

被引用文献数

3

---

&nbsp;&nbsp;The microstructures of a corrosion layer formed on the surface of two Japanese oldest coins, <i>Wadoukaichin</i> (surface color: dark brown and green) were studied. Compositions of these coins are that main element is Cu and Sn and traces are Pb, Fe and As. X-ray diffraction patterns show that copper di-hydroxide (Cu(OH)₂ 2H₂O), Cu_1.81S and Cu₂O are detected on the surface corrosion layer of dark brown sample, and Cu₂(CO₃)(OH)₂ (malachite), Cu₃(CO₃)₂(OH)₂ (azurite) and Cu₂O are detected on the surface corrosion layer of green sample. Optical microscope images show that the surface corrosion layer of dark brown sample is porous, and blue and green grains on the brown layer are existed on that of green sample. From spectrographs of these grains, the peak wavelength of green grains is matched to that of malachite, but this of blue grains is shifted to long wavelength side of about 40 nm at azurite on an influence of trace contaminations. The corrosion layer has two layers, surface layer is plate-like texture, and under layer is aggregation microstructure from TEM observation. The crystal structure of these two layers is matched to azurite from the electron beam diffraction patterns.<br>

著者

北田 正弘 高妻 洋成 肥塚 隆保 建石 徹

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.79, no.2, pp.71-75, 2015

被引用文献数

6

---

&nbsp;&nbsp;The mural of the <i>Takamatsuzuka</i> tumulus in Asuka, Nara prefecture, was painted in the 7-8th centuries. Red, green, blue, yellow, and black pigments are used in the mural. The microstructure of one of them, the red pigment, was described in the previous paper. In this study, the black pigment observed within the red pigment area has been investigated. An optical microscope, a scanning electron microscope, and a transmission electron microscope are utilized to examine the microstructure. Among the black particles, two different Fe compounds are observed. One is magnetite (Fe₃O₄) comprising small amounts of Ti, Al, and Mg, and the other is ilmenite (FeTiO₃) containing a small amount of Mg. In addition to the above compounds, an oxide particle containing Zr is also observed.<br>

著者

北田 正弘 高妻 洋成 建石 徹

出版者

公益社団法人 日本金属学会

雑誌

日本金属学会誌 (ISSN:00214876)

巻号頁・発行日

vol.79, no.8, pp.404-412, 2015 (Released:2015-08-01)

参考文献数

15

被引用文献数

2 4

---

The Takamatsuzuka tumulus was constructed in the 7th to 8th centuries at Asuka in Nara prefecture. The mural and wall surfaces are soiled and deteriorated by rainwater, mold, and other causes. The mural is painted on the stone wall that is coated with stucco. The stone walls are jointed with masonry joint stucco. The purpose of this investigation is to clarify the composition, crystal structure, and other material factors of the surface contaminant layer on the joint stucco. An X-ray computer tomography, an X-ray diffractometer, a scanning electron microscope, and a transmission electron microscope are utilized to examine the microstructure. The contaminant layer thickness is 0.2-0.3 mm. Kaolinite, muscovite, montmorillonite, hematite and a few silicates are detected from the contaminant layer. The compounds detected are constituents of soil-like clay, and most of them contain Fe. By transmission electron microscopy observation, the contaminant layer is found to consist of fine mineral grains, as mentioned above, most of which are acicular. The acicular grain size is approximately 0.2-1 μm in length and 0.015-0.2 μm in width. The grains are in a row parallel to the layer surface. The hematite grains are circular with diameters of 15-250 nm. In addition, iron titanate is observed. The yellowish brown color of the stucco surface is mainly due to iron ions contained in the above-mentioned compounds. It is thought that the grains deposited on the stucco surface from colloidal-like water containing the above-mentioned fine grains.

著者

田中 眞奈子 北田 正弘

出版者

日本金属学会

雑誌

日本金屬學會誌 (ISSN:00214876)

巻号頁・発行日

vol.76, no.8, pp.489-495, 2012-08-01

参考文献数

15

著者

北田 正弘 飯野 一朗 宮田 亮平 堀口 光彦 新山 栄

出版者

東京芸術大学

雑誌

東京芸術大学美術学部紀要 (ISSN:05638151)

巻号頁・発行日

vol.41, pp.5-17, 2004-07

被引用文献数

2