TY - JOUR
T1 - Metallurgical microstructure of the spear blade manufactured from the end of the Muromachi period to the Edo period
AU - Sugioka, Nahoko
AU - Kitada, Masahiro
AU - Nishijima, Masahiko
N1 - Copyright:
Copyright 2013 Elsevier B.V., All rights reserved.
PY - 2013/5
Y1 - 2013/5
N2 - 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 a-Fe (ferrite) grains. Optical micrographs of near-edge areas contain pearlite and martensite grains, and core areas contain pearlite and a-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.
AB - 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 a-Fe (ferrite) grains. Optical micrographs of near-edge areas contain pearlite and martensite grains, and core areas contain pearlite and a-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.
KW - Hammering
KW - Martensite
KW - Microstructure
KW - Nonmetallic inclusion
KW - Spear
KW - Steel
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U2 - 10.2320/jinstmet.J2012069
DO - 10.2320/jinstmet.J2012069
M3 - Article
AN - SCOPUS:84880090889
VL - 77
SP - 185
EP - 191
JO - Nippon Kinzoku Gakkaishi/Journal of the Japan Institute of Metals
JF - Nippon Kinzoku Gakkaishi/Journal of the Japan Institute of Metals
SN - 0021-4876
IS - 5
ER -