特集：超伝導体における磁束ピンニング◊✲ㄽᩥ‽㟼ⓗ☢ሙ࡟ࡼࡿ☢໬㐣⛬࡟࠾ࡅࡿ⁐⼥㉸ఏᑟࣂࣝࢡ☢▼ࡢᗘኚ໬࡜☢ሙ≉ᛶᒸ ᚭ㞝*1,†㸪ᶓᒣ ࿴ဢ*2㸪⸨௦ ༤அ*3㸪⬟Ⓩ ᏹ୐*3

Temperature Changes and Magnetic Properties of Melt-textured Superconducting Bulk
Magnets in the Magnetizing Processes using Quasi-static Magnetic Fields
Tetsuo OKA*1,†, Kazuya YOKOYAMA*2, Hiroyuki FUJISHIRO*3 and Koshichi NOTO*3
Synopsis: The temperature changes and magnetic-field trapping behaviors of melt-textured, single-domain Sm-Ba-Cu-O bulk
superconductors have been precisely investigated for magnetizing processes by means of quasi-static magnetic fields such as fieldcooling (FC) and zero field cooling (ZFC). The experiments were conducted in the temperature range of 40–80 K by
simultaneously measuring both the temperature and magnetic flux density. According to the balance of heat generation anddrainage, the temperature evolution profiles show distinctive behaviors of the invading and exhausting magnetic fluxes into andout of the HTS bulk magnet. The average temperature change during the FC process reached the maximum value of 4.63 K when
the sweep rate was 11.3 mT/s and the initial temperature was 45.6 K. In the ZFC process, both the temperature and magnetic flux
density kept increasing gradually even after the external magnetic field stopped growing at 5 T in the ascending field process. The
highest temperature rise due to the flux motion reached 4.6 K even when the sample was magnetized with at sweeping rate of
11.3 mT/s. As the behavior of temperature rise was different between the ascending and descending field processes, it issuggested that the magnetic fluxes in the processes invade and diffuse under different heating characteristics.
Keywords: magnetic field, bulk superconductor, field cooling, zero field cooling, refrigeratorἲ䛸␎䛩䠅䛾ᛶ⬟䛷䛒䜛䚹䛣䜜䜙䛾ᛶ⬟䜢ᚓ䜛䛯䜑䛻䛿䚸ບ☢㐣㻌 ࡣࡌࡵ࡟

⛬䛾ᙉຊ䛺☢ሙ䛻䜘䜛◚ቯ䛛䜙䝞䝹䜽☢▼䜢Ᏺ䜛䛯䜑䛻䚸ᶵᲔ⁐⼥ἲ䛷〇㐀䛥䜜䚸䛚䜒䛻 㻾㻱㻮㼍㻞㻯㼡㻟㻻㻣㻙㼥㻌 㻔㻾㻱 䛿 㼅㻘㻌 㻿㼙㻘㻌 㻳㼐ⓗ䛻⿵ᙉ䛩䜛ᢏ⾡䛜୙ྍḞ䛷䛒䜛䚹ྠ᫬䛻䚸☢ሙ䜢ྲྀ䜚ཤ䜛㝿䛷䛒䜚㻌 㻾㻱㻝㻞㻟 䛸␎グ䛥䜜䜛㻕䛸 㻾㻱㻞㻮㼍㻯㼡㻻㻡㻌 㻔㻾㻱㻞㻝㻝㻕䜢୺ᡂศ䛸䛻䛣䛾‽㟼ⓗ䛺☢ሙ䜢⏝䛔䛶䜒䚸☢᮰䛾㐠ື䛻䜘䜛Ⓨ⇕䛜↓䛩䜛㓟໬≀㧗ど䛷䛝䛺䛔䛣䛸䜒ሗ࿌䛥䜜䛶䛔䜛䠐䠈䠑䠅䚹㻌㉸ఏᑟ໬ྜ≀䛾⢒኱䛺⤖ᬗ䛿㉸ఏᑟ䝞䝹䜽☢▼䛸䜒࿧䜀䜜䚸እ㒊䛛䜙༳ຍ䛥䜜䛯☢ሙ䜢ᤕᤊ䛩䜛䛸䛔䜟䜖䜛㉸ఏᑟỌஂ☢▼䛸䛧䛶ᶵ⬟䛩䜛䛣䛸䛜▱䜙䜜䛶䛔䜛

䠍䠈䠎䠅

䚹䛣䛾

☢▼䛜Ⓨ⏕䛷䛝䜛☢ሙ䛿᭱኱ 㻝㻢㻌 㼀 䛒䜛䛔䛿 㻝㻣㻚㻞㻠㻌 㼀 䛸ሗ࿌䛥㼒㼕㼑㼘㼐㻌 㼙㼍㼓㼚㼑㼠㼕㼦㼍㼠㼕㼛㼚㻘㻌 㻼㻲㻹 ἲ䠅䛜䛒䜛䛜䚸☢᮰䛾⃭䛧䛔㐠ື䛻䜘䛳䛶኱䛝䛺Ⓨ⇕䛜ほ䛥䜜䚸䛣䛾䛣䛸䛜 㻲㻯 ἲ䛻ẚ䜉䛶ᤕᤊ䚸䛣䜜䜙䛾䝕䞊䝍䛿䝞䝹䜽☢▼䛜☢ሙ୰䛷䛭䛾㉸☢ሙᛶ⬟䛻ຎ䜛᭱኱䛾せᅉ䛻䛺䛳䛶䛔䜛䠒䠈䠓䠅䚹㻼㻲㻹 ἲ䛻䜘䜛Ⓨఏᑟ≧ែ䛻෭༷䛥䜜䛯ሙྜ䠄☢ሙ୰෭༷ἲ䚸㻲㼕㼑㼘㼐㻌㼏㼛㼛㼘㼕㼚㼓㻘㻌㻲㻯⇕䛿䝣䝷䝑䜽䝇䝆䝱䞁䝥䛻䜘䛳䛶㧗㏿䛻㣕䜃㎸䜐☢᮰䛻䜘䜛䛸ሗ

䜜䛶䛚䜚

䠏䠈䠐䠅

䝞䝹䜽☢▼䜢ບ☢䛩䜛᪉ἲ䛸䛧䛶䛿䝟䝹䝇╔☢ἲ䠄㻼㼡㼘㼟㼑㼐㻌࿌䛥䜜䛶䛔䜛䛜䠔䠅䚸☢ሙ䛾᣺䜛⯙䛔䛿䝟䝹䝇☢ሙ䜢༳ຍ䛩䜛๓㻌 㻾㼑㼏㼑㼕㼢㼑㼐㻌㻻㼏㼠㼛㼎㼑㼞㻌㻝㻜㻘㻌㻞㻜㻜㻥㻌㻖㻝㻌 ᪂₲኱Ꮫ㻌 㻌䛈㻥㻡㻜㻙㻞㻝㻤㻝㻌 ᪂₲┴᪂₲ᕷす༊஬༑ᔒ䠎䛾⏫ 㻤㻜㻡㻜㻌㻺㼕㼕㼓㼍㼠㼍㻌㼁㼚㼕㼢㼑㼞㼟㼕㼠㼥㻘㻌㻤㻜㻡㻜㻌㻵㼗㼍㼞㼍㼟㼔㼕㻙㻺㼕㼚㼛㼏㼔㼛㻘㻌㻺㼕㼟㼔㼕㻙㼗㼡㻘㻌 㻌㻺㼕㼕㼓㼍㼠㼍㻌㻥㻡㻜㻙㻞㻝㻤㻝㻘㻌㻶㼍㼜㼍㼚㻌㻖㻞㻌
㊊฼ᕤᴗ኱Ꮫ㻌 㻌䛈㻟㻞㻢㻙㻤㻡㻡㻤㻌 ᰣᮌ┴㊊฼ᕷ኱๓⏫ 㻞㻢㻤㻙㻝㻌㻭㼟㼔㼕㼗㼍㼓㼍㻌㻵㼚㼟㼠㼕㼠㼡㼠㼑㻌㼛㼒㻌㼀㼑㼏㼔㼚㼛㼘㼛㼓㼥㻘㻌 㻌㻞㻢㻤㻙㻝㻌㻻㼙㼍㼑㻙㼏㼔㼛㻘㻌㻭㼟㼔㼕㼗㼍㼓㼍㻘㻌㼀㼛㼏㼔㼕㼓㼕㻌㻟㻞㻢㻙㻤㻡㻡㻤㻘㻌㻶㼍㼜㼍㼚㻌㻌 㻌 㻖㻟
㻌ᒾᡭ኱Ꮫ㻌
䛈㻜㻞㻜㻙㻤㻡㻡㻝㻌 㻌 ᒾᡭ┴┒ᒸᕷୖ⏣ 㻠㻙㻟㻙㻡㻌㻵㼣㼍㼠㼑㻌㼁㼚㼕㼢㼑㼞㼟㼕㼠㼥㻘㻌㻠㻙㻟㻙㻡㻌㼁㼑㼠㼍㻘㻌㻹㼛㼞㼕㼛㼗㼍㻘㻌㻵㼣㼍㼠㼑㻌㻜㻞㻜㻙㻤㻡㻡㻝㻘㻌㻶㼍㼜㼍㼚㻌䈂㻌㻱㻙㼙㼍㼕㼘㻦㻌㼛㼗㼍㼠㻬㼑㼚㼓㻚㼚㼕㼕㼓㼍㼠㼍㻙㼡㻚㼍㼏㻚㼖㼜㻌 㻌

低温工学

44 巻 12 号

2009 年䛾☢ሙศᕸ䜢ᙉ䛟཯ᫎ䛩䜛䛯䜑䚸⧞䜚㏉䛧╔☢䜢⾜䛖䛣䛸䛜᭷ຠ䛷䛒䜛䠕䠅䚹䜎䛯䚸䛭䛾㝿䛾
䜜䛶䛔䜛

䠍䠌䠅

ᗘ䜢✚ᴟⓗ䛻ไᚚ䛩䜛䛣䛸䜒ヨ䜏䜙䚹㻼㻲㻹 ἲ䛻㛵䛧䛶⌧ᅾሗ࿌䛥䜜䛶䛔䜛ᤕᤊ☢ሙᛶ⬟䛾᭱㧗್䛿⸨௦䜙䛻䜘䜛 㻡㻚㻞㻌 㼀 䛷䛒䜛䚹䛣䛣䛷䛿☢ሙ౵ධ䛻
䜘䜛Ⓨ⇕䜢ᕦጁ䛻ᢚไ䛩䜛ᕤኵ䛜䛺䛥䜜䛶䛚䜚䚸䝞䝹䜽☢▼䛻཯᚟䛧䛶༳ຍ䛩䜛๓䛾☢ሙศᕸ䜢 㻹 Ꮠᆺ䛸䛩䜛䛣䛸䛜㔜せ䛷䛒䜛䛸ሗ࿌䛧䛶䛔䜛䠍䠍䠅䚹㻌䝊䝻☢ሙ෭༷ἲ䠄㼆㼑㼞㼛㻌㼒㼕㼑㼘㼐㻌㼏㼛㼛㼘㼕㼚㼓㻘㻌㼆㻲㻯 ἲ䠅䛿 㻼㻲㻹 ἲ䜢‽㟼ⓗ䛺☢ሙ䛷⾜䛳䛯ሙྜ䛻┦ᙜ䛧䚸䛩䛷䛻㉸ఏᑟ≧ែ䛻䛒䜛
587

mm

mm

Stainlesssteel ring(a)mmAluminacrystalCold stage

Vacuum chamber
Copper rod

(a)

(b)

Fig. 1 Illustrations of the magnetic pole of the experimental setup containing a HTS bulk magnet (a), and the positionsof the thermocouples and a Hall sensor on the bulk magnet surface (b).
䊋䊦䉪⏛⍹䉕Ყセ⊛ૐ䈇⏛႐ᄌൻㅦᐲ䋨㪪㫎㪼㪼㫇㩷㫉㪸㫋㪼䋩䈪ബ⏛䈜㪞㪪㪩䋩䈱䋲䈧䈱㗔ၞ䈪᷹ቯ䈘䉏䈢䇯䊋䊦䉪⏛⍹䈮ශട䈘䉏䉎⏛

䉎ᣇᴺ䈪䈅䉎䇯㪧㪝㪤 ᴺ䉋䉍䉅䈲䉎䈎䈮ૐㅦ䈪ଚ౉䈜䉎⏛᧤䈮䉋႐ 䈱 ᄌ ൻ 䈲䈠 䈱 ⴫ 㕙 䈱 ਛ ᔃ ㄭ ற 䈮 ⾍ ઃ 䈚䈢䊖䊷䊦䉶䊮䉰䉎⹜ᢱ䈱⏛ൻ᜼േ䈫䈠䈱㓙䈱⊒ᾲ䉕⹏ଔ䈜䉎䈖䈫䈏䈪䈐䉎䇯䊋䋨㪝㪅㪮㪅㪙㪼㫃㫃㪃㩷㪙㪟㪫㪐㪉㪈䋩䈮䉋䉍᷹ቯ䈘䉏䈢䇯㩷䊦䉪᧚ᢱ䈱⏛႐᝝ᝒ䉕䊖䊷䊦⚛ሶ䈪᷹ቯ䈜䉎ᚻᴺ䈲ᄙ⚿᥏䈪 ᷹ቯᣇᴺ 䈜䈪䈮⏕┙䈘䉏䇮⥃⇇⁁ᘒ䊝䊂䊦䈮䉋䈒ᢛว䈜䉎䈖䈫䈏⍮䉌䉏㪝㪚 ᴺ䈱႐ว䇮䊋䊦䉪⏛⍹䈏៞タ䈘䉏䈢⏛ᭂ䈲⿥વዉ䉸䊧䊉䈩䈇䉎䈖䈫䈎䉌䋱䋲䋩䇮䊋䊦䉪⏛⍹⴫㕙䈱᝝ᝒ⏛႐᷹ቯ䈫᷷ᐲ᷹ቯ䉟䊄⏛⍹䈱䊗䉝ౝㇱ䈮ᝌ౉䈘䉏䇮䈠䈱Ᏹવዉ⁁ᘒ䈪䋵㩷 㪫 䈱⏛䉕㑐ㅪ䈨䈔䉎䈖䈫䈏䈪䈐䉎䇯ᧄ⎇ⓥ䈪䈲䇮Ḱ㕒⊛䈭⏛႐䈮䉋䉎႐䉕ශട䈘䉏䈢䉁䉁䇮㪫㪺 એਅ䈱ᚲቯ䈱᷷ᐲ䉁䈪಄ළ䈘䉏䈢䇯䈖ബ⏛ㆊ⒟䈪䈱⊒ᾲ䈫᷷ᐲ਄᣹䉕♽⛔⊛䈭᷹ቯ䊂䊷䉺䈫䈚䈩✚䈱䈱䈤䈠䉏䈡䉏䈱⏛႐ᄌൻㅦᐲ䈪⏛႐䉕䉷䊨䉁䈪ᷫ⴮䈚䈢䈱᜝䈜䉎䈖䈫䉕⋡⊛䈫䈜䉎䇯ബ⏛ᴺ䈫䈚䈩 㪝㪚 ᴺ䈫 㪱㪝㪚 ᴺ䉕ข䉍਄䈤䈮䇮䊗䉝䈱ᄖㇱ䈮ข䉍಴䈚䈩⏛ᭂ⴫㕙䈱⏛᧤ኒᐲ䉕䊖䊷䊦䈕䇮䈠䉏䉌䈱⏛ൻㆊ⒟䉕ㅢ䈛䈩䇮ዊဳ಄ಓᯏ䉕↪䈇䈢ᭂૐ᷷䉶䊮䉰䉕⿛ᩏ䈚䈩᷹ቯ䈚䈢䇯Ḱ㕒⊛䈭⏛႐䈱ශട䈮䈲⋥ធ಄䈪䈱䊋䊦䉪⏛⍹䈻䈱⏛႐䈱ଚ౉᜼േ䉕䇮᷷ᐲᄌൻ䈫᝝ᝒ⏛႐ළᑼ䈱⿥વዉ䉸䊧䊉䉟䊄⏛⍹䋨㪡㪘㪪㪫㪜㪚䇮㪡㪤㪫㪛㪄㪌㪫㪈㪇㪇䋩䈏↪䈇䈱ⷰὐ䈎䉌ታ㛎⊛䈮⹏ଔ䈜䉎䇯䉌䉏䈢䇯㩷㪱㪝㪚 ᴺ䈱႐ว䇮䈜䈪䈮⿥વዉ⁁ᘒ䈮䈅䈦䈩⌕⏛䈘䉏䈩䈇䈭 ታ㛎ᣇᴺ

䈇䊋䊦䉪⏛⍹䈮ኻ䈚䇮Ḱ㕒⊛䈭⏛႐䉕ฦ䇱䈱⏛႐ᄌൻㅦᐲ䈪 ⿥વዉࡃ࡞ࠢ⏛⍹ߣߘߩታ㛎ⵝ⟎  ශട䈚䈩䈇䈒䇯ᦨᄢ 㪌㩷㪫 䈱⏛႐䈮଻䈦䈢䈱䈤䇮ห৻䈱⏛႐ᄌൻ㪝㫀㪾㪅㩷㪈 䈮ታ㛎ⵝ⟎䉕␜䈜䇯ṁⲢᴺ䈮䉋䉍ห๺㋶ᬺ䈮䉋䈦䈩૞ㅦᐲ䈪䉷䊨⏛႐䉁䈪ᷫ⏛䈜䉎䊒䊨䊐䉜䉟䊦䈮ᓥ䈉䇯㪝㪚 ᴺ䈭䉌䈶ᚑ䈘䉏䈢⏛᳇⊛䈮න৻䈭 㪪㫄 ♽䊋䊦䉪⏛⍹䈏䇮એਅ䈮␜䈜 㪝㪚䈮 㪱㪝㪚 ᴺ䈠䉏䈡䉏䈱႐ว䇮ബ⏛㐿ᆎ䈱᷷ᐲ䈲䉮䊷䊦䊄䊓䉾䊄䋵䋩ᴺ䈫 㪱㪝㪚 ᴺ䈮䉋䉎ബ⏛ታ㛎䈮↪䈇䉌䉏䈢 䇯⌀ⓨኈེ䈱ౝㇱ䉕 㪊㪏㩷 䌋䇮㪋㪇㩷 䌋䇮㪌㪇㩷 䌋䇮㪍㪇㩷 㪢 䈱䈇䈝䉏䈎䈮⸳ቯ䈚䈢䇯䈖䈖䈪䈲䈮ⵝႯ䈘䉏䈢䈖䈱䊋䊦䉪䈱ኸᴺ䈲⋥ᓘ 㪋㪌㩷 㫄㫄䇮ෘ䈘 㪈㪌㩷 㫄㫄 䈪䈖䉏䉌䉕಄ළ᷷ᐲ䈫ቯ⟵䈜䉎䇯৻ᣇ䇮䈖䉏䉌䈱಄ළ᷷ᐲ䈮ኻ䈚䇮䈅䉎䇯⹜ᢱ䈲䉴䊁䊮䊧䉴䋨㪪㪬㪪㪊㪇㪋䋩䈱䊥䊮䉫䈮ၒ䉄ㄟ䉖䈪⵬ᒝ䈚䇮䊋䊦䉪⏛⍹䈱⴫㕙䈮⸳⟎䈘䉏䈢䋵ᧄ䈱ᾲ㔚ኻ䈱ᐔဋ᷷ᐲ䈲䈠ᾲવዉ䈮ఝ䉏䉎䉝䊦䊚䊅න⚿᥏䈱䊑䊨䉾䉪䉕੺䈚䈩㌃䈱䉮䊷䊦䉏䈡䉏 㪋㪌㩷㪢䇮㩷 㪋㪏㩷㪢䇮㪌㪎㩷㪢䇮㪍㪏㩷㪢㩷 䈪䈅䉎䇯䉁䈢䇮⏛႐ᄌൻㅦᐲ

䊄䉴䊁䊷䉳䈮ข䉍ઃ䈔䉌䉏䈢䇯䈖䉏䉌䈲 㪞㪤 ಄ಓᯏ䈱䉮䊷䊦䊄䈲 㪉㪅㪌㪊㩷㫄㪫㪆㫊䇮㩷 㪌㪅㪇㪍㩷㫄㪫㪆㫊䇮㩷 㪈㪈㪅㪊㩷㫄㪫㪆㫊 䈱ਛ䈎䉌ㆬ䈳䉏䈢䇯㩷䊓䉾䊄䈮ធ⛯䈘䉏䈩ឃᾲ䈘䉏䉎䈏䇮䈠䈱಄ಓㇱ䋨䉮䊷䊦䊄䊓䉾䊄䈫๭䈹䋩䈮䈲೙ᓮ↪䈱᷷ᐲ⸘䈫䊍䊷䉺䈏ข䉍ઃ䈔䉌䉏䈩䈇䉎䇯䊍䊷䉺䈲⹜ᢱ䉕⏛႐ශട೨䈱ೋᦼ᷷ᐲ䈮⺞ᢛ䈜䉎䈏䇮ബ⏛ਛ䈲⹜ᢱ䈱᷷ᐲ਄᣹䈮䉋䉍䈠䈱಴ജ䈲ᱛ䉁䉍䇮ബ⏛ᓟ䈲ೋᦼ᷷ᐲ䈮ะ䈔䈩᷷⺞䈘䉏䉎䇯಄ಓᯏ䈲䉝䉟䉲䊮♖ᯏ⵾ 㪞㪩㪈㪇㪊 䈪䈅

Table 1 Temperature changes at the center of the surface during FC
magnetized bulk magnet

䊋䊦䉪⏛⍹䈱⴫㕙䈮䈲䋵ᧄ䈱㌃㪄䉮䊮䉴䉺䊮䉺䊮ᾲ㔚ኻ䋨㪫㪈㪄

6ZHHS UDWH
P7V,QLWLDO
WHPSHUDWXUH
.

7LPH V

7HPSHUDWXUHFKDQJH .

㪫㪌 䈪␜䈜䋩䈏䊋䊦䉪⏛⍹⴫㕙䈱 㪝㫀㪾㪅㪈䋨䌢䋩䈮␜䈜૏⟎䈮⾍ઃ䈘









䉏 䈢 䇯 䈠 䉏 䉌 䈱 ᷷ ᐲ 䈲 ⚿ ᥏ ᚑ 㐳 䉕 ␜ 䈜 〔 䋨 㪞㫉㫆㫎㫋㪿㩷 㫊㪼㪺㫋㫆㫉㩷









㪹㫆㫌㫅㪻㪸㫉㫐㪃㩷㪞㪪㪙 䈫⇛䈜䋩䈫䈠䈱㑆䈱㗔ၞ䋨㪞㫉㫆㫎㫋㪿㩷㫊㪼㪺㫋㫆㫉㩷㫉㪼㪾㫀㫆㫅㪃㩷









䉍䇮㪈㩷㫂㪮 䈱౉ജ䈪 㪎㪎㩷㪢 䈮䈍䈇䈩 㪈㪌㩷㪮 䈱಄ಓ಴ജ䉕䉅䈧䇯㩷

588

TEION KOGAKU（J. Cryo. Soc. Jpn.）Vol. 44 No. 12（2009）




(a)

   (b)    Fig. 2 Magnetic field distribution measured on the magnetic pole surface activated by the FC process (a), and across-section of the magnetic distribution as compared to those of ZFC (b).
䛧䛯䚹㻲㻯 ἲ䛻䜘䜜䜀䚸ᤕᤊ☢ሙศᕸ䛿෇㗹≧䛷䚸ෆ㒊䛻ㄏᑟᐇ㦂⤖ᯝ࡜⪃ᐹ䛥䜜䜛㟁ὶ䛜෇ᙧ䛻ὶ䜜䜛ᵝᏊ䜢♧䛩䚹୍᪉䚸㼆㻲㻯 ἲ䛷䛿୰ኸ ‽㟼ⓗ࡞☢ሙࢆ⏝࠸ࡓບ☢࡛ࡢ☢ሙᤕᤊᛶ⬟㒊ศ䛜ᖹᆠ䛺ྎᙧ䛻䛺䜚䚸䝞䝹䜽☢▼䜈䛾☢ሙ䛾౵ධ䛜༑ศ䠢䡅䡃㻚㻌㻞㻔㼍㻕䛻䚸ᮏᐇ㦂䛷‽㟼ⓗ☢ሙ䛾༳ຍ䛻䜘䛳䛶ບ☢䛧䛯䝞䛷䛺䛔䛣䛸䜢ఛ䜟䛫䜛䚹㻌䝹䜽☢▼䛾☢ሙศᕸ䛾୍౛䜢♧䛩䚹䜾䝷䝣䛿⇕㟁ᑐ 㼀㻝 䛾఩⨨ ☢ሙ୰෭༷㸦)&㸧ἲ࡛ࡢ䛷䠑䠌㻌 㻷 䛛䜙䚸☢ሙኚ໬㏿ᗘ䠑䠊䠌䠒㻌 䡉㼀㻛㼟 䛷䠑㻌 㼀 䜎䛷 㻲㻯 ἲ䛻㻲㼕㼓㻚㻌㻟 䛻䚸㻲㻯 ἲ䛷䛾☢ሙኚ໬㏿ᗘ䜢䠍䠍䠊䠏㻌 䡉㼀㻛㼟 䛸䛧䚸෭༷䜘䛳䛶ບ☢䛧䛯ᚋ䛾ᤕᤊ☢ሙศᕸ䜢䚸┿✵ᐜჾእ㒊䛛䜙䛯⤖ᯝ䛷䛒䜛䚹

ᐃ䛧ᐃ఩⨨䛿ᐜჾእ㠃䛛䜙䠌䠊䠑㻌 䡉䡉䚸䝞䝹䜽☢▼⾲㠃䛛䜙䠏䠊䠑㻌 䡉䡉䛾㊥㞳䛻䛒䜛䚹᭱኱䠎䠊䠓䠌㻌 㼀 䛾☢ሙ䜢Ⓨ⏕ᗘ࡜☢ሙࡢኚ໬

ᗘ䠏䠔㻌 㻷 䛛䜙䛾䝞䝹䜽☢▼⾲㠃䛷䛾ᗘኚ໬䜢䚸㻲㼕㼓㻚㻌 㻝㻔㼎㻕䛻♧䛩఩⨨ 㼀㻝㻙㼀㻡 䛷 ᐃ䛧䛯⤖ᯝ䜢♧䛩䚹ᅗ䛻䛿䝞䝹䜽☢▼䛾⾲㠃୰ኸ௜㏆䛷ᐃ䛧䛯☢ሙኚ໬䜢ྠ᫬䛻♧䛩䚹ィ䛥䜜䛯䛧䛶䛔䜛䛜䚸䝞䝹䜽☢▼䛻≉᭷䛾ྠᚰ෇≧䛾☢ሙศᕸ䜢࿊䛩䚹ᗘ䛿⇕㟁ᑐ䛤䛸䛻ⱝᖸ䛾ศᕸ䛜䛒䜚䛭䛾㍑ṇ䛿᏶඲䛷䛿䛺ᅗ୰䛻◚⥺䛷♧䛩 㻳㻿㻮 ୖ䛾☢ሙศᕸ䛿ⱝᖸእഃ䛻ᙇ䜚ฟ䛧䚸䛔䛜䚸☢ሙ䛾ῶ⾶䛻࿧ᛂ䛧䛶 ᗘ䛿୍ᩧ䛻ୖ᪼䛧䚸䛭䛾㝿䛾☢

䛣䛾㒊ศ䛷䛾⮫⏺㟁ὶᐦᗘ 㻶㼏 䛜௚䛾㒊ศ䜘䜚ඃ䜜䜛䛣䛸䜢⾲䛧᮰䛾ὶฟ䛻క䛳䛶኱䛝䛺Ⓨ⇕䛜㉳䛣䛳䛶䛔䜛䛣䛸䜢♧䛩䚹䛶䛔䜛䚹㻌ୖ᪼䛜ῶ☢㐣⛬䛾ᙜึ䛛䜙ጞ䜎䜛䛾䛿䚸ῶ☢㛤ጞ䛸ྠ᫬䛻䝞䝹㻲㼕㼓㻚㻌 㻞㻔㼎㻕䛻䚸㻲㻯 ἲ䛸 㼆㻲㻯 ἲ䛻䜘䜛ບ☢ᚋ䛾☢ሙศᕸ䜢♧䛩䚹ᗘ䜽䛾➃㠃䛛䜙☢᮰䛜ὶฟ䛧䛰䛩䛣䛸䜢⾲䛧䛶䛔䜛䚹䜎䛯䚸☢ሙኚ䛭䜜䛮䜜䛾☢ሙኚ໬㏿ᗘ䜢䠑䠊䠌䠒㻌 䡉㼀㻛㼟 䛸䠍䠍䠊䠏㻌 䡉㼀㻛㼟 䛸䛧䚸໬䛾㏿ᗘ䛜୍ᐃ䛷䛒䜛䛻䜒㛵䜟䜙䛪䚸☢ሙศᕸ䛾᭱኱Ⅼ䜢㏻䜛᩿㠃䠄ᅗ୰䛾ᐇ⥺䠅䛾☢ሙศᕸ䜢⾲グᐃ䛷䛺䛔䛾䛿䚸ヨᩱ୰ኸ㒊௜㏆䛷䛾☢ሙኚ໬䛜➃㠃䛾䛭䜜䛻

Fig. 3 Temperature changes measured on the bulk magnet㻌
sample surface (thermocouple T1) during the FC process.

Fig. 4 Time evolutions of the temperatures at the center ofthe surface during the FC magnetizing process.㻌

低温工学

44 巻 12 号

2009 年ᐃ䛥䜜䛯ῶ☢㏿ᗘ䛜୍

589

(a)

(b)

Fig. 5 Time evolutions of the average temperatures and the magnetic fields on the bulk surface by the FC process with sweep rates (a)11.3 mT/s and (b) 2.53 mT/s.㩷ㆃ䉏䉎䈖䈫䉕ᗧ๧䈚䈩䈇䉎䇯⹦⚦䈭ⷰኤ䈮䉋䉏䈳䇮ೋᦼ䈮䈠䈱᷷㪝㫀㪾㪅㩷 㪋 䈮䇮䊋䊦䉪⏛⍹䈱ਛᔃ䈮⸳⟎䈚䈢ᾲ㔚ኻ 㪫㪈 䈪᷹ቯ䈚ᐲ਄᣹䈏㊰䈇䈱䈲䇮⏛᧤䈱ㆇേ䈮䉋䉎⏛႐ᄌൻ䈏䈠䈱ᷫ⴮ೋ䈢᷷ᐲᄌൻ䉕䇮㪊 ᳓Ḱ䈱⏛႐ᄌൻㅦᐲ䈮㑐䈚䈩␜䈜䇯䈖䉏䉌䈱ᦼ䈮䈲䊋䊦䉪⏛⍹ో૕䈮෸䈳䈝䇮䈠䈱๟ㄝㇱ䈱䉂䈱ᄌൻ䈪䈅䊂䊷䉺䉕 㪫㪸㪹㫃㪼㩷 㪈 䈮␜䈜䇯䈖䈱䈫䈐಄ළ᷷ᐲ䈲 㪌㪇㩷 㪢䇮䊋䊦䉪᷷䉎䈖䈫䉕ᥧ␜䈚䈩䈇䉎䇯᷷ᐲ਄᣹䈏ᵴ⊒ൻ䈜䉎Ბ㓏䈮⥋䉎䈫䇮⹜ᐲ 㪫㪈 䈱ೋᦼ᷷ᐲ䈲 㪌㪎㪄㪌㪏㩷 㪢 䈪䈅䉎䇯᷷ᐲ਄᣹䈲⏛႐ᄌൻㅦᢱో૕䈪⏛᧤䈏ㆇേ䈚䈩䈇䉎䈖䈫䉕␜䈜䇯⊒ᾲ䈲䊋䊦䉪⏛⍹䈱ᐲ䈏ㅦ䈇䈾䈬ᄢ䈐䈒᣿⏕䈭䊏䊷䉪䉕␜䈜䇯䈠䈱᷷ᐲ䈲ᦨᄢ䈪䋵䋮๟ㄝㇱ䈎䉌ᆎ䉁䉍䇮ᄖㇱ⏛႐䈱ᷫዋ䈫䈫䉅䈮⹜ᢱో૕䈮᜛ᄢ䈜䋴㪎㩷 㪢 䈮䈭䉍䇮䈠䈱 㪉 ୚䇮㪋 ୚䈱ᤨ㑆䉕䈎䈔䈩䉉䈦䈒䉍ബ⏛䈚䈢႐䉎䈎䉌䈪䈅䉎䇯⏛႐䈏䉷䊨䈮೔㆐䈚䈢ᤨὐ䈪⊒ᾲ䈲ᱛ䉁䈦䈩᷷ว䈱䋳䋮䋵䋸㩷 䌋䇮䋲䋮䋴䋸㩷 㪢 䉕ᄢ䈐䈒਄࿁䈦䈢䇯ᝄ᏷䈱ห䈛⏛႐䈱ᐲ䈲䊏䊷䉪䉕␜䈜䈏䇮୘䇱䈱ᾲ㔚ኻ䈮䈧䈇䈩䈠䈱䊏䊷䉪૏⟎䈏ශട䈪䈅䈦䈩䉅䇮ᤨ㑆ᒰ䈢䉍䈱ᛩ౉㔚ജ䈲ශട䈘䉏䉎ᤨ㑆䈮ห䈛䈪䈅䉎䈖䈫䈲䇮ᄖㇱ⏛႐䈏஗ᱛ䈚䈢ᤨὐ䈪ዪᚲ⊛䈭⏛᧤䈱䉋䈦䈩ᄌ䉒䉎䈖䈫䈎䉌䇮ශടᤨ㑆䈱㆑䈇䈎䉌䇮৻ቯ䈱಄ළ⢻ജ䈫ㆇേ䈏䈖䉏䈮๭ᔕ䈚䈩ᱛ䉁䉍䇮䊏䊮ᱛ䉄៊ᄬ䈏䉷䊨䈫䈭䈦䈩⊒ᾲ䈱䊋䊤䊮䉴䈮䉋䈦䈩᷷ᐲ਄᣹䈏⇣䈭䉎䈖䈫䈲ℂ⸃䈘䉏䉎䇯㩷䈏หᤨ䈮஗ᱛ䈚䈢䈢䉄䈪䈅䉎䇯㩷㪝㫀㪾㪅㩷 㪌 䈮䋴᳓Ḱ䈱಄ළ᷷ᐲ䈎䉌ⴕ䈦䈢 㪝㪚 ᴺ䈪䈱䇮㪌 ᧄ䈱ᾲ㔚ኻ䈱ᐔဋ᷷ᐲ䈫䇮⴫㕙ਛᄩઃㄭ䈪䈱⏛᧤ኒᐲ䈱ᤨ㑆ᄌൻ䉕␜䈜䇯㪝㫀㪾㪅㩷 㪌㩿㪸㪀䈮␜䈜⏛႐ᄌൻㅦᐲ䈲䋱䋱䋮䋳㩷 䌭㪫㪆㫊䇮䋨㪹䋩䈪䈲䋲䋮䋵䋳㩷 䌭㪫㪆㫊 䈪䈅䉎䇯⏛႐䈱ᷫ⴮ㆊ⒟䈪䈱⊒ᾲ䈲䈇䈝䉏䈱᷷ᐲ䈪䉅ห᭽䈮⿠䈖䉍䇮㩿㪸㪀䈫㩿㪹㪀䈇䈝䉏䉅ᄖㇱ⏛႐䈏䉷䊨䈫䈭䉎ᤨὐ䈪᷷ᐲ䈲䊏䊷䉪䉕␜䈜䇯᝝ᝒ⏛႐䈲ೋᦼ᷷ᐲ䈮ᒝ䈒ଐሽ䈚䇮ૐ᷷䈾䈬ബ⏛ᓟ䈱᝝ᝒ⏛႐䈲ᄢ䈐䈇䇯㩷㪝㫀㪾㪅㩷 㪍 䈮䈍䈔䉎᷷ᐲ䈱ᦨᄢ୯䈫䇮ᦨ⚳⊛䈭᝝ᝒ⏛႐䈱୯䉕䇮䈠䈱ೋᦼ᷷ᐲ䈫⏛႐ᄌൻㅦᐲ䈮ኻ䈚䈩␜䈜䇯᷷ᐲᄌൻ䈲ೋᦼ
Table 2 Temperature changes (K) in the ZFC magnetizing process
6ZHHS UDWH
P7V



Fig. 6 The maximum values of the temperature changes
and the trapped magnetic flux densities during the FC
magnetizing process as a function of the sweep rates.

590



,QLWLDO
WHPSHUDWXUH .

7HPSHUDWXUHFKDQJH .

7UDSSHGILHOG
7




























TEION KOGAKU（J. Cryo. Soc. Jpn.）Vol. 44 No. 12（2009）⏛႐䈪ബ⏛䈚䈢႐ว䈱⴫㕙᷷ᐲ䈫⏛᧤ኒᐲ䈱ᤨ㑆ᄌൻ䉕␜䈜䇯䉫䊤䊐䈱ᮮゲ䈲䌫䌳䈪⴫⸥䈚䈩䈅䉎䇯䉮䊷䊦䊄䊓䉾䊄䈱಄ළ᷷ᐲ䈲䋵䋰㩷 㪢 䈪䇮䈖䈱䈫䈐ബ⏛೨䈱䋵ᧄ䈱ᾲ㔚ኻ䈱ᐔဋ᷷ᐲ䈲䋶䋰䋮䋵䋷㩷㪢 䈪䈅䈦䈢䇯⏛႐ᄌൻㅦᐲ䈲䋱䋱䋮䋳㩷 䌭㪫㪆㫊 䈪䈅䉎䇯⏛႐ශട䈱㐿ᆎ䈫䈫䉅䈮䊋䊦䉪⏛⍹䈱⴫㕙᷷ᐲ䈲ᕆỗ䈮਄᣹䈚䇮⏛᧤䈱ଚ౉䈮䉋䉎⊒ᾲ䈱ലᨐ䉕␜䈜䇯ᄖㇱ⏛႐䈏ᱛ䉁䉎䈫᷷ᐲ਄᣹䈲䊏䊷䉪䉕๒䈜䉎䇯䈇䈦䈢䉖ᱛ䉁䈦䈢᷷ᐲ਄᣹䈲䊏䊷䉪ᓟ䈮ᰴ╙䈮਄᣹䈚䇮หᤨ䈮⏛᧤ኒᐲ䈲䉪䊥䊷䊒⃻⽎䉕␜䈚䈩䉉䈦䈒䉍䈫Ⴧട䈜䉎䇯䋵㪫 䈱ᄖㇱ⏛႐䈮ᦑ䈘䉏䉎䈏䇮ਛᄩઃㄭ䈲⚂䋲㩷 㪫 䈪䈅䉎䈢䉄䇮⹜ᢱౝㇱ䈻䈱⏛᧤ଚ౉䈲⛮⛯⊛䈮⿠䈖䉍⛯䈔䉎䇯䋳㩷 䌫䌳䉕ㆊ䈑䉎䈫䇮⊒ᾲ䈫಄ළ䈱䊋䊤䊮䉴䈮䉋䉍᷷ᐲ䈲䈚䈣䈇䈮ਅ㒠䈮ォ䈛䉎䈏䇮䋱䋸㩷 䌫䌳䈪ᄖㇱ⏛႐䈏ᷫዋ䈮ォ䈛䉎䈫䇮⏛᧤ኒᐲ䈲ᕆỗ䈮ᷫዋ䈜䉎䈫䈫䉅䈮䇮⹜ᢱ᷷ᐲ䈲ౣ䈶ᕆ਄᣹䈜䉎䇯ᄖㇱ⏛႐䈏䉷䊨䈮䉅䈬䉎䈫䈐䈮᷷ᐲ䈲䊏䊷䉪䈫䈭䉍䇮䈠䈱ᓟ䈲ೋᦼ᷷ᐲ䈮಄ළ䈘䉏䉎䇯ᦨ⚳⊛䈭᝝ᝒ⏛႐䈲䊋䊦䉪⏛⍹ਛᄩઃㄭ䈪䋱䋮䋲䋱㩷
Fig. 7

Time evolution of the average temperature and themagnetic flux density measured on the bulk surface using a Hallsensor during the ZFC process.㩷㪫 䈪䈅䈦䈢䇯㩷
䈖䉏䉌䈱ᝄ䉎⥰䈇䈱⹦⚦䉕⏛႐ᄌൻㅦᐲ䈏䋱䋱䋮䋳㩷 䌭㪫㪆㫊 䈱႐ว䈮䈧䈇䈩㩷 㪝㫀㪾㪅㩷 䋸䈮␜䈜䇯㪝㫀㪾㪅㩷 㪏㩿㪸㪀䈮␜䈜䉋䈉䈮䇮䋵䋰䋰㩷 䌳䉁䈪䈱ᄖㇱ⏛႐䈱Ⴧട䈮઻䈦䈩᷷ᐲ䈫⴫㕙䈱⏛᧤ኒᐲ䈲䈫䉅䈮᷷ᐲ䈮ᄢ䈐䈒ଐሽ䈚䇮ૐ᷷䈾䈬ૐ䈇⹜ᢱ䈱Ყᾲ䈫ᒝ䈇䊏䊮ᱛ䉄Ⴧട䈚䇮䋵㩷 㪫 䈮㆐䈚䈩䉅䇮᷷ᐲ䈫หᤨ䈮✭䉇䈎䈮਄᣹䈜䉎䇯䋵䋰䋰㩷ജ䈱䈢䉄ᄢ䈐䈭᷷ᐲ਄᣹䉕␜䈜䇯㪝㫀㪾㪅㩷 㪉 䈮␜䈜䉋䈉䈮䇮ኈེᄖ䌳䈪㍈䈇䊏䊷䉪䉕␜䈜䈱䈲䇮⏛႐ଚ౉䈏஗ᱛ䈚䈢⍍㑆䈮䇮વᾲㇱ䈪᷹ቯ䈜䉏䈳᝝ᝒ⏛႐䈮ᄢ䈐䈭㆑䈇䈲⷗䉌䉏䈭䈎䈦䈢䇯䈚䈎ㇱ᧚䉇䊋䊦䉪⏛⍹䈭䈬಄ළ䈘䉏䈢䈜䈼䈩䈱ㇱಽ䈮ᾲ䈏વ៝䈚䈚 㪝㫀㪾㪅㩷 㪌 䈫 㪝㫀㪾㪅㩷 㪍 䈎䉌䇮⹜ᢱ⴫㕙䈪ⷰኤ䈜䉏䈳䇮䋶䋰㩷 㪢 એ਄䈱䈩䈇䈒䈢䉄䈪䈅䉎䈫⠨䈋䉌䉏䉎䇯䈖䈱䈖䈫䈎䉌䇮ଚ౉䈜䉎⏛᧤䈮䉋㗔ၞ䈪⊒ᾲ䈏᝝ᝒ⏛႐䈱ᕈ⢻䈮⋥ធᓇ㗀䈚䈩䈒䉎䉋䈉䈮䈭䉎䇯㩷䉎⊒ᾲ䈲ਇဋ⾰䈅䉎䈇䈲ዪᚲ⊛䈮⿠䈖䈦䈩䈇䉎䈫ផኤ䈘䉏䉎䇯㪫㪸㪹㫃㪼㩷 㪉 䈮␜䈜䉋䈉䈮䇮᷹ቯ䈚䈢 㪌 ὐ䈱ᐔဋ᷷ᐲ䈮㑐䈚䈩 㪝㪚㪝㫀㪾㪅㩷 㪏㩿䌢㪀䈮␜䈜⏛႐ᷫ⴮䈱ㆊ⒟䈪䈲䇮వ䈱 㪝㪚 ᴺ䈫ห᭽䈮⏛ᴺ䈮䈍䈔䉎ᦨᄢ䈱᷷ᐲ਄᣹䈲䇮䈭䉎䈼䈒ૐ᷷䉁䈪಄ළ䈚䇮䈎䈧᧤䈱ᵹ಴䈮䉋䉎⊒ᾲ䈏ᕆỗ䈭᷷ᐲ਄᣹䉕䈍䈖䈜䇯ห᭽䈮 㪝㫀㪾㪅㩷 㪐⏛႐ᄌൻㅦᐲ䈏ᄢ䈐䈇႐ว䈮ᓧ䉌䉏䈢䋴䋮䋶䋳㩷 㪢 䈪䈅䉎䇯৻ᣇ䇮䈮⏛႐ᄌൻㅦᐲ䈏䉋䉍✭䉇䈎䈭䋵䋮䋰䋶㩷 䌭㪫㪆㫊 䈱႐ว䉕␜䈜䇯వ䋲䋮䋵䋳㩷 䌭㪫㪆㫊 䈱Ყセ⊛✭䉇䈎䈭ബ⏛䉕ⴕ䈦䈩䉅䇮䋵䋰㩷 㪢 䈎䉌䈱䈱႐ว䉋䉍⏛႐ଚ౉䈏✭䉇䈎䈭䈢䉄䇮䋵㩷 㪫 䈮㆐䈚䈢㓙䈱᷷ᐲബ⏛䈪䋲䋮䋵㩷 㪢 䈱᷷ᐲ਄᣹䈏䈅䉎䈖䈫䈲⹺⼂䈚䈩䈍䈒ᔅⷐ䈏䈅䉎䇯䊏䊷䉪䈲Ṗ䉌䈎䈫䈭䉎䇯䈖䈱ᓟ䈮⏛႐䈱䉪䊥䊷䊒⃻⽎䈮䉋䉎ଚ౉ ࠯ࡠ⏛႐಄ළ㧔<(%㧕ᴺߢߩ᷷ᐲߣ⏛႐ߩᄌൻ

䈪᷷ᐲ䈲਄᣹䈜䉎䇯㪝㪝㫀㪾㪅㩷㪐㩿㪹㪀䈮␜䈜ᷫ⏛ㆊ⒟䈪䈲䇮⏛᧤䈱ᵹ಴㪝㫀㪾㪅㩷 㪎 䈮䇮ห䈛⹜ᢱ䈮ኻ䈚䈩 㪱㪝㪚 ᴺ䈮䉋䈦䈩䋵㩷 㪫 䈱Ḱ㕒⊛䈮䉋䉎⊒ᾲ䈫಄ಓᯏ䈻䈱ឃᾲ䈲䊋䊤䊮䉴䈚䇮✭䉇䈎䈭᷷ᐲૐਅ

(a)

(b)

Fig. 8 Time evolutions of the average temperature and magnetic flux density during the ZFC 5 T process with a sweep rate of
11.3 mT/s in the (a) ascending and (b) descending field stages.㩷

低温工学

44 巻 12 号

2009 年

591

(a)Fig. 9(b)Time evolutions of the average temperature and magnetic flux density during the ZFC 5 T process with a sweep rate of

5.06 mT/s in the (a) ascending and (b) descending field stages.

䈏⛯䈒䇯㩷䈖䉏䉌䋶䋰㩷 㪢 ㄭற䈱ೋᦼ᷷ᐲ䈎䉌᷹ቯ䈚䈢᷷ᐲᄌൻ䉕 㪝㫀㪾㪅㩷㪈㪇 䈮䇮䈠䈱䊂䊷䉺䉕 㪫㪸㪹㫃㪼㩷 䋳䈮␜䈜䇯⏛᧤䉪䊥䊷䊒Ბ㓏䈱ㆊ⒟䉕฽䉁䈝䇮ᄖㇱ⏛႐䈏ᄌൻ䈜䉎㑆䈣䈔䈱᷷ᐲᄌൻ䉕䇮ห᭽䈮㩷䋵䋰㩷 㪢 ㄭற䈪ታ㛎䈚䈢᷷ᐲᄌൻ䈱䊂䊷䉺䈫䈫䉅䈮␜䈜䇯Ⴧ⏛ㆊ⒟䈪䈲䇮⏛႐ᄌൻㅦᐲ䈮䈎䈎䉒䉌䈝䈮䋴㩷 㪢 ⒟ᐲ䈱᷷ᐲ਄᣹䈏䈅䉎䇯䈇䈝䉏䉅⏛႐䈏䋵㩷 㪫 䈪஗ᱛ䈚䈢㓙䈱᝝ᝒ⏛႐䈲䈾䈿䋱䋮䋶㩷㪫 ⒟ᐲ䈪䈅䉎䈖䈫䈎䉌䇮㪝㪚 䈪䈱ᷫ⏛ㆊ⒟䈱䉋䈉䈭⹜ᢱో૕䈪䈱⏛᧤ㆇേ䈲⿠䈖䉌䈝䇮ᒝ䈒ㆤ⭁䈘䉏䈩䇮⏛႐ಽᏓ䈅䉁䉍ᄌ䉒䉌䈭䈇䈫⠨䈋䉌䉏䉎䇯䈖䈱䈖䈫䈎䉌䇮ᛩ౉䈘䉏䈢㔚ജ㊂䈮ᄢ䈐䈭Ꮕ䈲䈭䈒䇮᷷ᐲ਄᣹䈫䈚䈩䈲ห⒟ᐲ䈫䈭䉎䈫⠨䈋䉌䉏䉎䇯㩷䈖䉏䈮ኻ䈚䇮ᷫ⏛ㆊ⒟䈪䈲⊒ᾲ䈫಄ළ䈱䊋䊤䊮䉴䈮䉋䈦䈩᷷ᐲᄌൻ䈲਄᣹䈫ਅ㒠䈮ಽ䈎䉏䇮ㆃ䈇ᷫ⏛䈪䈲ឃᾲ䈏ᡰ㈩⊛䈪䈅䉎䇯䈖䉏䉌䈱⚿ᨐ䈎䉌䇮⏛᧤䈱ଚ౉䈫ᵹ಴䈱ㆊ⒟䈪䈲䈠䈱ᝄ䉎⥰䈇䈮ᄢ䈐䈭㆑䈇䈏䈅䉎䈖䈫䈏䉒䈎䉎䇯ଚ౉೨䈫ᵹ಴೨䈪䈲䋴㩷 㪢䈱᷷ᐲᏅ䈏䈅䉎䈢䉄䇮෩ኒ䈮䈲᧚ᢱ䈱Ყᾲ䈱㆑䈇䉕⠨ᘦ䈜䉎

Fig. 10 The sweep-rate dependence of the temperaturechanges during the ZFC magnetizing process.

ᔅⷐ䈲䈅䉎䈏䇮಄ಓᯏ䈮䉋䉎ឃᾲ䈱ㅦᐲ䈲䈾䈿ห䈛䈫⠨䈋䉌䉏䉎䈎䉌䇮⏛᧤䈏ଚ౉䈜䉎㓙䈱⊒ᾲ䈲ᄢ䈐䈒䇮ᵹ಴ᤨ䈲ዊ䈘䈇䈫⸒⊛䈭⏛႐䈱ශട䈮䈍䈔䉎⏛᧤䈱ᝄ䉎⥰䈇䈱ో⽩䉕᣿䉌䈎䈮䈚䈩䈋䉎䇯㪞㪪㪙 䈫 㪞㪪㪩 䈮䈍䈔䉎 㪡㪺 䈱⋧㆑䈏䈖䈱ὐ䈮ᓇ㗀䈜䉎䈫ផኤ䈇䈒䇯䈖䉏䉌䈱䊂䊷䉺⫾Ⓧ䈮䉋䈦䈩䇮䉋䉍◲ଢ䈭⌕⏛ᴺ䈫䈚䈩䈱䈪䈐䉎䈖䈫䈎䉌䇮䋵䈎ᚲ䈱ᾲ㔚ኻ䈮䉋䉎᷷ᐲ⸘᷹⚿ᨐ䈮䈲䇮䉋䉍⹦㪧㪝㪤 䈮⍮⷗䉕↢䈎䈚䇮䉋䉍ᒝജ䈭⏛႐᝝ᝒ䉕⋡ᜰ䈜䈖䈫䈏䈪䈐⚦䈭ಽᨆ䈏ᔅⷐ䈪䈅䉎䇯੹ᓟ䈲⏛᧤䈱ଚ౉䈫ᵹ಴䈪⊒ᾲ䈱ᝄ䉎䉎䈫⠨䈋䉎䇯⥰䈇䈏⇣䈭䉎ὐ䉕ਛᔃ䈮䈠䈱⃻⽎䉕⹏ଔ䈚䈩䈇䈒䈖䈫䈪䇮Ḱ㕒⚿⺰

Table 3 Temperature changes (K) in ZFC magnetizing process
6ZHHS UDWH
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 ṁⲢᴺ䈮䉋䉎ᄢဳ䈱 㪪㫄 ♽䊋䊦䉪⏛⍹䉕಄ಓᯏ䉕↪䈇䈩ᭂૐ,QLWLDO
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+GRZQ䈠䈱᷷ᐲᄌൻ䈫⏛႐᝝ᝒ䈱Ꮒⷞ⊛䈭ᝄ䉎⥰䈇䉕䇮♽⛔⊛䈭ታ

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㛎䈮䉋䉍⹏ଔ䈚䈢䇯ೋᦼ᷷ᐲ䋴䋵䋮䋶㩷 㪢 䈎䉌䋱䋱䋮䋳㩷 䌭㪫㪆㫊 䈱⏛႐



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ᄌൻㅦᐲ䈪䇮䋵㩷 㪫 䈱 㪝㪚 ᴺ䈮䉋䈦䈩ബ⏛䈚䈢႐ว䇮ᦨᄢ䋴䋮䋶㪊㩷



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'LUHFWLRQ᷷䈮಄ළ䈚䇮䈖䉏䈮 㪝㪚 ᴺ䈭䉌䈶䈮 㪱㪝㪚 ᴺ䈮䉋䉎ബ⏛䉕ⴕ䈇䇮㪢 䈱᷷ᐲ਄᣹䈏䈅䈦䈢䈏䇮৻ᣇ䇮䋲䋮䋵䋶㩷 䌭㪫㪆㫊 䈱ૐㅦ䈪䈱ബ⏛䈪䉅䋴䋷䋮䋶㩷 㪢 䈪䋲䋮䋲䋳㩷 㪢 䈱᷷ᐲ਄᣹䈏䈅䉍䇮Ḱ㕒⊛⏛႐䈮䉋䉎
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䛻ᚑ஦䚹ᖹᡂ 㻝㻤 ᖺ䜘䜚᪂₲኱ᏛᕤᏛ㒊㝃ᒓᕤ

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field of YBCO single-domain samples using pulse magnetizationfrom 77 K to 20 K”, 8th European Conference on Applied
Superconductivity, J. Phys.: Conf. Ser. 97 (2008) 012047
9)⬟ Ⓩ ᏹ ୐᫛࿴ 㻝㻞 ᖺ 㻝㻜 ᭶ 㻞㻢 ᪥⏕䚹᫛࿴ 㻟㻡 ᖺᐩᒣ኱U. Mizutani, T. Oka, Y. Ito, Y. Yanagi, M. Yoshikawa and H. Ikuta,Ꮫᩥ⌮Ꮫ㒊༞ᴗ䚹᫛࿴ 㻟㻣 ᖺᮾ໭኱Ꮫ኱Ꮫ㝔⌮Ꮫ◊✲⛉ಟ஢䚹ྠᖺ

“Low temperature pulsed field magnetization of trapped fieldᮾ໭኱Ꮫ㔠ᒓᮦᩱ◊✲ᡤຓᡭ䚹᫛࿴ 㻠㻤 ᖺྠຓᩍᤵ䚹᫛࿴ 㻡㻢 ᖺ᪥

magnets and their applications”, TEION KOGAKU 34 (1999) 654-

⡿ඹྠ◊✲ὴ㐵◊✲ဨ䚹ᖹᡂඖᖺᒾᡭ኱ᏛᕤᏛ㒊ᩍᤵ䚹ᖹᡂ 㻝㻝 ᖺ

661 (in Japanese)Ỉ㇂Ᏹ୍㑻ࠊᒸ ᚭ㞝ࠊఀ⸨ెᏕࠊᰗ 㝧௓ࠊྜྷᕝ㞞❶ࠊ⏕⏣༤ᚿ㸸㺀ᤕᤊ☢ሙ࣐ࢢࢿࢵࢺࡢప
పࣃࣝࢫ╔☢࡜ࡑࡢᛂ⏝㺁ࠊ

ᕤᏛ 34㸦1999㸧654-661

ᒾᡭ┴ᆅᇦ⤖㞟ᆺඹྠ◊✲஦ᴗ䛾◊✲⤫ᣓ䚹ᖹᡂ 㻝㻞 ᖺ䜘䜚పᏛ఍㛗䚹ᖹᡂ 㻝㻡 ᖺᒾᡭ኱Ꮫྡ㄃ᩍᤵ䚸⌧ᅾ䛻⮳䜛䚹ᑓ㛛䛿㉸ఏᑟᮦᩱ㛤Ⓨ䛺䛹䚹ཷ㈹䛿ᖹᡂ 㻟 ᖺᗘ኱ᒣグᛕㄽᩥ㈹䛺䛹䚹⌮Ꮫ༤ኈ䚹㻌10) M. Sander, U. Sutter, R. Koch and M. Klaser: “Pulsed
magnetization of HTS bulk parts at T<77K”, Supercond. Sci.
Technol. 13 (2000) 841-845

低温工学

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2009 年ᕤ

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