宇宙航空研究開発機構研究開発資料 JAXA Research and Development Memorandum

キャビテーション噴流法による ロケットポンプ材料の壊食特性の比較

2011年２月

JAXA-RM-10-017

宇宙航空研究開発機構研究開発資料

JAXA Research and Development Memorandum

川崎　聡，菊田　研吾，吉田　義樹

宇宙航空研究開発機構

Japan Aerospace Exploration Agency

宇 宙

航 空

研 究

開 発

機 構

研 究

開 発

資 料

ɖȁȁ໹଼23ාˎ࠮ˎ඾਋ັȪReceivedˎ February 2011ȫ

ɖˍ ֳಐ࿶௣ηΛΏοϋུ໐ȁֳಐ࿶௣ࠏଔૺܿ੅ࡄݪٳอΓϋΗȽȪSpace Transportation Propulsion Research and Development Center, Space Transportation Mission Directorateȫ

ɖ2 Ժ IHIȪIHI Corporationȫ

΅λΫΞȜΏοϋ໨ၠ༹ͥ͢ͅυΉΛΠεϋίऺၳ͈ٟ૙අ଻͈๤ڛ

୼ॄȁ௛^ɖ1Ȃ݊നȁࡄࢁ^ɖ2Ȃ݌നȁ݅ਏ^ɖ1 ȁȁȁȁȁȁȁȁȁȁ

Comparison of Cavitation Erosion Properties of the Materials Used in Rocket Comparison of Cavitation Erosion Properties of the Materials Used in Rocket Comparison of Cavitation Erosion Properties of the Materials Used in Rocket Comparison of Cavitation Erosion Properties of the Materials Used in Rocket Comparison of Cavitation Erosion Properties of the Materials Used in Rocket

Turbopump by Cavitating Jet Method Turbopump by Cavitating Jet Method Turbopump by Cavitating Jet Method Turbopump by Cavitating Jet Method Turbopump by Cavitating Jet Method

Satoshi KAWASAKI^ɖ1, Kengo KIKUTA^ɖ2 and Yoshiki YOSHIDA^ɖ1 ABSTRACT

ABSTRACTABSTRACT ABSTRACT ABSTRACT

ȁTo compare the cavitation erosion properties, the typical materials used in the rocket engine turbopump were tested by cavitating water jet method. Generally, the solid materials of inducer or impeller have high erosion resistance, but the silver plating used in the inducer liner is much lower one. The addition agents can improve the erosion resistance of silver plating, which was about ten times higher than normal silver plating. Furthermore, we tried an experiment with cavitating liquid nitrogen jet. The specimen of pure aluminum was slightly damaged by cavitating liquid nitrogen jet after ten minutes test. It indicated possibility of cryogenic cavitation erosion test.

Keywords KeywordsKeywords Keywords

Keywords : Cavitation, Erosion, Rocket, Turbopump, Cavitating Jet, Cryogenic

ˍȅ੣࡞

ȁυΉΛΠ΀ϋΐϋဥΗȜδεϋίͅอ୆̳ͥ΅λΫΞ ȜΏοϋ͉Ȃஉٝ΅λΫΞȜΏοϋ͞΅λΫΞȜΏοϋ

΍Ȝΐ͈̈́̓ະհ೰࡛ય͈ါ֦̹͂̈́ͥ͛Ȃၠఘഎ௰࿂

̥͈ͣࡄݪ͉ତఉ̩ૺ̧̹͛ͣͦ̀^ˍȫȃ༷֚ȂυΉΛΠ ဥεϋί๊͉֚ॲުဥεϋί͂๤͓̀׋ഢশۼ̦ޭ౤ͅ

ౣ̞̹͛Ȃ΅λΫΞȜΏοϋٟ૙ͅ۾̳ͥࡄݪ͉ဒͤࡉ

൚̹̞ͣ̈́ȃ๊֚ॲުဥεϋί͈໦࿤͉́΅λΫΞȜΏ οϋٟ૙͈ࡄݪ͉ࡣ̩̥࣐̤ͣͩͦ̀ͤȂٟ૙අ଻͈Ο ȜΗαȜΑاٟ͞૙ထ௶༹༷͈೹մ̦̈́̓ૺ̞ͭ́ͥ^ˎȫ

,ˏȫ,ːȫȃࣽࢃȂυΉΛΠ͈ठঀဥاͬ࿒ঐ̳ાࣣȂಿশ ۼ׋ഢ̤̫ͥͅ΅λΫΞȜΏοϋٟ૙͈࿚ఴ͉ΗȜδε ϋί͈૞ှ଻͞ιϋΞ΢ϋΑ͈۷ത̥ͣਹါ̈́هఴ͂̈́

ͥȃ

ȁུࡄݪ͉́υΉΛΠဥεϋίͅঀဥ̯ͦͥయນഎ̈́ਅ ș͈ऺၳȪྫࢠऺȫͅచ̱̀΅λΫΞȜΏοϋ໨ၠ༹ͅ

ٟͥ͢૙দࡑ࣐̞ͬȂٟ૙අ଻ͬ಺͓̹ȃ̹͘ȂͼϋΟ

νȜ΍ρͼ΢͉ͼϋΟνȜ΍͈͂୪૘ͅచ̳ͥอغ͈ဲ

ଷ͞ͼϋΟνȜ΍అੱ͈ဲଷ͈̹͛ͅȂ߆ιΛ΅͈̈́̓

ੜ౾̦ঔ̯̞ͦ̀ͥȃ߆ιΛ΅͉ͼϋΟνȜ΍ͅဥ̞ͣ

ͦͥऺၳ͂๤ڛ̱̀਴̥̞̹ͣ͛Ȃεϋί໐຦͈ಎ͉́

΅λΫΞȜΏοϋٟ૙̦ૺ࣐̱օ̞͂ࣉ̢ͣͦͥȃ̷̭

́߆ιΛ΅ऺ͈ٟ૙අ଻ͬ಺͓ͥ͂͂͜ͅȂତਅ႒͈ι Λ΅ऺ͈ٟ૙අ଻ࠗ͜௶̱̀๤ڛ̱̹ȃ

ȁષܱদࡑ͉କͤ͢ͅ৘ঔ̱̹̦Ȃ৘ܥ͈ଔૺस͉סఘ କள͞סఘॸள͈̈́̓ޭ೩أၠఘ̜́ͥȃ̷̭́Ȃסఘ ಊளͬဥ̞̹΅λΫΞȜΏοϋ໨ၠ৘ࡑ௡౾ͬୋै̱Ȃ দࡑ༌ͅ΅λΫΞȜΏοϋ໨ၠͬ൚̀ͥ৘ࡑͬ৘ঔ̱̹ȃ

̷͈৘ࡑ༹༷̤͍͢৘ࡑࠫض̞̾̀͜ͅ༭̳࣬ͥȃ

ˎȅރদऺၳ

ȁນ1ͅރদऺၳ͈֚။ͬΫΛ΃ȜΑࣁ̯͂͂͜ͅা̳ȃ υΉΛΠဥεϋί́΅λΫΞȜΏοϋ͈גޣͬ਋̫ͥ໐

຦̱͉͂̀ȂͼϋΟνȜ΍͞ͼϋβρȂ̷͈ͦͣਔս͈

ΉȜΏϋΈ͞ρͼ΢̦ݷ̬ͣͦͥȃ̭͈ͦͣ໐຦ͅঀဥ

̯ͦͥయນഎ̈́ऺၳ̱͂̀ȂSUS304^ȂTi^ࣣ߄ȂNi^ܖ಼

ࣣ߄ȂFeܖ಼ࣣ߄Ȃಚ௮Alࣣ߄ͬރদऺၳ̱͂̀ဥ̞̹ȃ

̹͘Ȃ४ચऺၳ̱͂̀੗ͺσηȂ੗ൾȂ૯ᱻٟͥ͢ͅ૙

দࡑ࣐̹̽͜ȃιΛ΅ऺ̞͉̾̀ͅȂͼϋΟνȜ΍ρͼ

΢́ဥ̞ͣͦͥ೒ુ͈߆ιΛ΅ऺ͂͂͜ͅȂഞحसȪΓ τϋȂͺϋΙκϋ൝ȫͬح̢̹߆ιΛ΅ऺȂ߄ιΛ΅ऺȂ Ni^ιΛ΅ऺȂCrιΛ΅ऺͬރদऺၳ̱̹͂ȃιΛ΅ऺ͈

༦ऺ͉஠̀SUS304̜́ͤȂιΛ΅࢚̯͉200Ђḿ̜

ͥȃ

ȁރদऺၳ͈ࣁ̯ࠗ௶͉υΛ·;Ϳσࣁ̯দࡑܥͤ͢ͅ

࣐̞Ȃນˍ͉ͅΫΛ΃ȜΑࣁ̯۟ͅॳ̱̹౵ͬা̱̞̀

ͥȃ̹̺̱Ȃ̞̩̥͈̾ऺၳ̞͉̾̀ͅυΛ·;Ϳσࣁ

̯ࠗ௶̀ͅୃږͅΟȜΗ̦৾ං̧̥̹̹́̈́̽͛Ȃளऺ

ιȜ΃͈́ࠗ௶ࠫض͞ڎਅ঩ၳȂ໲ࡃ൝̥ͣଔ೰̱̹౵

ͬ४ࣉ౵̱͂̀া̳ȃ

ˏȅদࡑ༹༷

ȁٟ૙দࡑ͉ȂLichtarowicz̽̀͢ͅࣉմ̯ͦȂASTM G134 ^5ȫܰڒͅ೰̹͛ͣͦ΅λΫΞȜΏοϋ໨ၠ༷ͥ͢ͅ

༹ͅ੔̲̀৘ঔ̱̹Ȫঌ์ΦΒσͬဥ̞̤̀ͤȂΦΒσ ࠂ͉ASTM͂൳̜̦֚́ͥȂΦΒσࢹ௮̦։̈́ͥȫȃ଎1

૆̯̹ͦକͬίρϋΐλȜεϋί̀ͅحգ̱ȂΦΒσͅ

̽̀͢΅λΫΞȜΏοϋΐͿΛΠͬอ୆̵̯̀দࡑ༌ͅ

ΐͿΛΠͬ൚ٟ̀̀૙ͬ୆̵̲̯ͥȃ

ȁঀဥၠఘ͉କ̜́ͤȂঀဥΦΒσࠂ͉Ћ0.40ȂΦΒσ

੄࢛͂দࡑ༌͈ݻၗȪΑΗϋΡ΂έݻၗȫ͉15mm^̱͂

̹ȃգႁૄ࠯͉ષၠգႁPuɁ17.7MPaAȂئၠգႁPdɁ

0.56MPaA̱͂Ȃষ৆͈೰݅ͤ͢ͅݥ̹͛΅λΫΞȜΏ

οϋତ͉Ј= 0.032̜́ͥȃ σ = −

−

p p

p p

d v

u d

ȁPvȇ཈გ૊ܨգ

ȁུࡄݪ̧͉̺̫́ͥఉਅ͈ऺၳ̞̾̀ͅΟȜΗͬਓਬ

̳༷ͥૻ́ૺ̹̹͛͛Ȃٟ૙௸ഽ̦डఱ௸ഽܢͅో̱̹

͂฻౯̱̹౲ٴ́Ȃ̷͈দࡑ༌ٟͥ͢ͅ૙দࡑ͉ਞၭ̱

̹ȃ

ȁٟ૙ͥ͢ͅৗၾࡘઁၾ͉ഩঊഛฉͬဥ̞̀1mg^͈ୈഽ

́ࠗ௶̱̹ȃఘୟࡘઁၾ͉ৗၾࡘઁၾͬদࡑऺၳ͈ྟഽ

́ੰ̱̀ݥ̹͛ȃນ࿂ࠁે͉τȜΎ་պࠗͤࠗ͢ͅ௶̱

̹ȃ̹͘Ȃ̞̩̥͈ٟ̾૙দࡑ̤̞̀ࣞͅ௸ഽΫΟ΂΃

ιρͥ͢ͅज़ג࣐̞ͬȂ΅λΫΞȜΏοϋ໨ၠ͈ݷ൲ͬ

۷ख़̱̹ȃ

ȁסఘಊளͥ͢ͅ΅λΫΞȜΏοϋ໨ၠদࡑ͈મळ̾ͅ

̞͉̀Ȃ4.3ࣜͅা̳ȃ

ːȅদࡑࠫض͂ࣉख़

4.2ȁ΅λΫΞȜΏοϋ໨ၠ͈ݷ൲

ȁ଎2ࣞͅ௸ഽΫΟ΂΃ιρ́ज़ג̱̹΅λΫΞȜΏο ϋ໨ၠ͈ݷ൲ͬা̳ȃ΅λΫΞȜΏοϋ໨ၠ͈ݷ൲͉ர ५̦ͣࣞ௸ഽৢ૯̽̀͢ͅમळͬྶ̥̱̞̦ͣ̀ͥͅ^˒ȫȂ

ུদࡑ̷̤̞͈̀͜ͅݷ൲ͬ஛ྶͅږ෇̧̳̭̦ͥ͂́

̹ȃΦΒσ̥ͣ౯௽എ̈́ܨ༺׌̦༶੄̯ͦȪ଎2ӱȫȂܨ

༺׌̦দࡑ༌ͅ઩ඏ̱Ȫ଎2ӲȫȂςϋΈે͈־΅λΫΞ ȜΏοϋ̦দࡑ༌ນ࿂ષͅ୆̲̀ڐఱ̱Ȫ଎2ӳȫȂςϋ Έે͈־΅λΫΞȜΏοϋ̦༲ٟ̱Ȫ଎2^{ӴȫȂ̷͈߃ཌྷ}

ٟ́૙̦ૺ࣐̱̞̀ͥȃ౯௽എͅอ୆̳ͥܨ༺׌͈อ୆

ਔ෨ତ͉4^ȡ5kHź̜ͤȂர५͈ͣࡄݪ́ࠗ௶̱̹ܨ༺

׌༶੄ਔܢ^˒ȫ͂΂ȜΘ͉֚౿̱̞̀ͥȪΦΒσࠁે͉։

̈́ͥȫȃ

4.2ȁڎރদऺၳ͈ٟ૙ેޙٟ͂૙අ଻

ȁ଎3̤͍͢଎4͉ͅȂྫࢠऺ̤͍͢ιΛ΅ऺ͈ٟ૙দࡑ

ࢃ͈দࡑ༌ນ࿂ેఠ͈ৢ૯̷̸ͬͦͦা̳ȃ਱໦ٟͅ૙

̦ૺ࣐̱̞̞̀̈́·υθιΛ΅ͬੰ̞͉̀Ȃ଎2ͅা̱

̹΅λΫΞȜΏοϋ໨ၠ͈ݷ൲ͅచ؊̱̀ςϋΈેٟͅ

Table 1 Test specimens Material Vickers

Hardness Remarks

Solid

SUS304 200 Stainless steel

Ti-6Al-4V 340 Titanium alloy

Ni Alloy 718 443 Ni-base superalloy

A286 350 Fe-base superalloy

A356 75 Cast Aluminum Alloy

A1050BD-H14 41 ^ˏȫ Pure Aluminum

C1100BD-H 92 ^ˏȫ Pure Copper

C3604 107 Free-cutting brass

Plating (Base material : SUS304) Silver(Ag) plating 60

Silver(Ag) plating

with addition agents 132 Addition agents : Selenium, Antimony

Gold(Au) plating Ƚ

Nickel(Ni) plating 190 Chromium (Cr)

plating 260

Fig.1^ȁErosion test apparatus by cavitating water jet

㪝㫀㫃㫋㪼㫉

㪝

㪤㫆㫋㫆㫉

㪤

Ðìõîçåò  ðõíð

㪧 㪘

㪘㪺㪺㫌㫄㫌㫃㪸㫋㫆㫉

㪫㪼㫊㫋㩷㪺㪿㪸㫄㪹㪼㫉

㪚

Test piece Direction of jet flow

Motor Plunger pump

Tank

Test chamber

Accumulator

Standoff distance

Test apparatus Test chamber

૙̦ૺ̞ͭ́ͥအঊ̦໦̥ͥȃ̭͈ٟͦͣ૙͈ζ·ΰ

အ௖͉ྫࢠऺ̤͍͢ιΛ΅ऺ͂͜൳̲̜́ͥȃࣁ̞ऺၳ

ȪNi Alloy 718^ȂTi-6Al-4VȂΣΛΉσιΛ΅̈́̓ȫ͉ٟ́

૙̦ૺ࣐̱̹ςϋΈે͈໐໦ٟ͂૙̦ૺ̞̞ͭ́̈́ಎ؇

໐ ̦ ྶ ږ ͅ ໦ ̥ ͦ ̀ ̞ ͥ ̦ Ȃ ๤ ڛ എ ਴ ͣ ̥ ̞ ऺ ၳ ȪA1050BD-H14ȂA356Ȃ߆ιΛ΅ऺ̈́̓ȫ͉́ಎ؇໐͘

ٟ́૙̦ૺ̞ͭ́ͥȃ

ȁ଎5ͅȂNi Alloy 718͂A356̤͍͢߆ιΛ΅ऺ͈ນ࿂

ࠁેͬা̳ȃNi Alloy 718͉ಎ૤ͅచ̱͕͖̀చઠഎ́

޳ٟ֚ͅ૙̱̞̦̀ͥȂA356͉́๱చઠ́ະ޳ٟ֚ͅ૙

̱̞̀ͥȃ߆ιΛ΅ऺ͉́ಎ؇໐ͅܖ੔࿂ͤ͢େͤષ̦

ͥ໐໦̦ࡉ̦ͣͦͥȂΣΛΉσιΛ΅͞ഞحसͬح̢̹

߆ιΛ΅͈̠̈́͢ࣁ̞ιΛ΅ऺ͉́Ni Alloy 718^͂൳̲

̠̈́͢ນ࿂ࠁેͬা̱Ȃಎ؇໐ນ࿂͈ޭ౤̈́་ࠁ͞େͤ

ષ̦͉ͤږ෇̯̥̹ͦ̈́̽ȃ

ȁ΅λΫΞȜΏοϋ໨ၠͥ͢ͅڎރদऺၳ͈ζ·ΰٟ

૙ેޙ͈֑̞͉ࣁ̯ͥ͢ͅגޣ̦঑෻എ̜́ͤȂྫࢠऺ

Ԙ ԙ

Ԛ ԛ

Fig.2ȁBehavior of cavitating jet onto the test specimen

͂ιΛ΅ऺͥ͢ͅגޣ͉઀̯̞͂ࣉ̢ͣͦͥȃιΛ΅ऺ

͈ાࣣȂٟ૙૬̯̦ιΛ΅࢚̯೾ഽ́͘ૺ͚͂༦ऺ͈ג ޣͤ͢ͅྫࢠऺ͉͂։ٟ̈́ͥ૙ેޙͬা̳خෝ଻͜ࣉ̢

̦ͣͦͥȂུࡄݪ́ږ෇̱̹डఱٟ૙૬̯100^ȡ150µm

೾ഽȪιΛ΅࢚̯͉200Ђmȫ͉́͘Ȃඅͅ༦ऺ͈גޣ

̦੄࡛̳̠ͥ̈́͢අಭ͉ࡉ̥̹ͣͦ̈́̽ȃ

ȁ଎6ͅڎރদऺၳ͈ఘୟࡘઁၾ͈་اͬা̳ȃ̴̞ͦ

͈ރদऺၳ͜দࡑٳইࢃ͉ٟ૙̦͕͂ͭ̓ૺ̞̈́͘Ȫٟ

૙௸ഽ̦઀̯̞ȫஆ໖ܢ̦ږ෇̯ͦȂ̷͈ࢃȂఘୟࡘઁ

ၾ͉ೄ஌എͅ௩ح̱ٟ̀૙௸ഽ̦डఱ͂̈́ͥडఱ௸ഽܢ

ͅঢ̞̽̀ͥȃఘୟࡘઁၾ͈་اΩΗȜϋ͉ྫࢠऺ͂ι Λ΅ऺ͂͜൳အ̜́ͤȂιΛ΅ऺඅခ͈ΩΗȜϋ͉ࡉͣ

̥̹ͦ̈́̽ȃ̤̈́Ȃ·υθιΛ΅ऺ͉8শۼ͈ٟ૙দࡑ

ࢃ͜ৗၾ་ا͉ࡉ̴ͣͦȂถ̞୥̦̞̞̾̀ͥ೾ഽ̜́

̹̽Ȫ଎4४ચȫȃ

ȁ଎7ͅڎރদऺၳ͈ΫΛ΃ȜΑࣁ̯ٟ͂૙೷ࢯ͈۾߸

ͬၰచତΈρέ́া̳ȃ̭̭́Ȃٟ૙೷ࢯ͉डఱ௸ഽܢ

͈́ఘୟࡘઁၾ͈߹̧Ȫ଎6͈ఘୟࡘઁၾ͈߹̧͈डఱ

౵ȫ͈ݙତ̱͂̀ݥ̹͛ȃ४ચऺၳ̜́ͥ੗ͺσηȂ੗

ൾȂ૯ᱻ͉ٟ૙̦ૺ̺ͭેఠ͈́ࠗ௶͈͙̜̹́ͥ͛Ȃ

̭̭͉́ఘୟࡘઁၾͬ௙দࡑশۼ́ੰ̱̹౵ٟͬ૙೷ࢯ

̱͂̀ե̹̽ȃ̤̈́Ȃ଎ಎ͈֚തङ஌͉Ni Alloy 718͂ ߆ιΛ΅ऺ͈ത̺ͬࠫͭ๤ڛဥ͈༞੩஌̜́ͥȃ ȁٟ૙೷ࢯ͉ऺၳ͈ࣁ̯͂ၻ̞௖۾ͬা̳̭̦͂༭̯࣬

̞̦ͦ̀ͥ^ˏȫȂུদࡑ̤̞̀͜ͅྫࢠऺ̤͍͢ιΛ΅ऺ

͂͜໵̵̀ၻ̞௖۾ͬা̱̞̀ͥȃΑΞϋτΑ͉حࢥࣁ

ا͈גޣͤ͢ͅࣁ̯ͅచ̱̀ఛٟ૙଻̦࿹̞ͦ̀ͥ͂༭

̯̞̦࣬ͦ̀ͥ^ˎȫȂུদࡑ̤̞̀͜ͅSUS304͉́൳အ

͈ࠫض̦ං̹ͣͦȃͼϋΟνȜ΍͞ͼϋβρ͈ளऺ̱͂

̀ဥ̞ͣͦͥNi Alloy 718ȂTi-6Al-4VȂA286͉ऺၳ̷͈

Fig.3ȁEroded surfaces of test specimens (solid materials)

㪪㪬㪪㪊㪇㪋㩷㩿㪊㪉㪿㪀 㪫㫀㪄㪍㪘㫃㪄㪋㪭㩷㩿㪊㪉㪿㪀 㪥㫀㩷㪘㫃㫃㫆㫐㩷㪎㪈㪏㩷㩿㪌㪍㪿㪀 㪘㪉㪏㪍㩷㩿㪊㪍㪿㪀

㪘㪊㪌㪍㩷㩿㪈㪿㪀 㪘㪈㪇㪌㪇㪙㪛㪄㪟㪈㪋㩷㩿㪇㪅㪌㪿㪀 㪚㪈㪈㪇㪇㪙㪛㪄㪟㩷㩿㪉㪿㪀 㪚㪊㪍㪇㪋㩷㩿㪊㪿㪀

㪪㫀㫃㫍㪼㫉㩷㫇㫃㪸㫋㫀㫅㪾㩷㩿㪈㪿㪀 㪪㫀㫃㫍㪼㫉㩷㫇㫃㪸㫋㫀㫅㪾㩷㫎㫀㫋㪿 㪸㪻㪻㫀㫋㫀㫆㫅㩷㪸㪾㪼㫅㫋㫊㩷㩿㪐㪿㪀

㪞㫆㫃㪻㩷㫇㫃㪸㫋㫀㫅㪾㩷㩿㪈㪿㪀

㪥㫀㪺㫂㪼㫃㩷㫇㫃㪸㫋㫀㫅㪾㩷㩿㪏㪿㪀 㪚㪿㫉㫆㫄㫀㫌㫄㩷㫇㫃㪸㫋㫀㫅㪾㩷㩿㪏㪿㪀

͈̦͜ࣁ̞̹͛Ȃ̴̞ٟͦ͜૙೷ࢯ͉ఱ̧̞ȃ̹̺̱Ȃ A286͉ࣁ̯ͅచ̳ͥఛٟ૙଻͉ఈ͈ऺၳ͂๤͓̀͞͞Ⴆ

̞̽̀ͥȃ

ȁ߆ιΛ΅ऺ͉Ȃ४ચऺၳ̜́ͥ੗ͺσηͬੰུ̫͊ࡄ ݪ́ဥ̞̹ރদऺၳ͈ಎٟ́૙೷ࢯ̦ड͜઀̯̞ȃͼϋ ΟνȜ΍ρͼ΢͈߆ιΛ΅ঔࢥ࿒എ̥ͣȂ߆ιΛ΅͉ͼ ϋΟνȜ΍ऺၳͤ͢਴̥̩̳ͣͥຈါ̦̜ͤȂٟ૙೷ࢯ

̦઀̯̩̭͉̜̈́ͥ͂ͥ೾ഽ๰̫̞ͣͦ̈́ȃਲ̽̀߫ͤ

༐̱׋ဥͥ͢ͅಿশۼ׋ഢͬ࿒ঐ̳ાࣣȂ߆ιΛ΅͈΅

λΫΞȜΏοϋٟ૙̞̾̀ͅ਱໦ಕփ̳ͥຈါ̦̜ͥȃ

̱̥̱Ȃഞحसͬح̢̹߆ιΛ΅͉೒ુ͈߆ιΛ΅ͤ͢

10෼ٟ૙೷ࢯ̦ఱ̧̩ȂΣΛΉσιΛ΅ͅ߃̞ٟ૙೷ࢯ

ͬা̱Ȃࣁ̯ͅచ̳ͥఛٟ૙଻͜࿹̞ͦ̀ͥȃഞحसͬ

ح̢̹߆ιΛ΅̤͍͢ΣΛΉσιΛ΅͂͜೒ુ͈߆ιΛ

΅͂๤͓ٟ̀૙໐͈ல̯̦ळ̥̩Ȃٟ૙ι΃ΣΒθ֑ͅ

̞̦̜ͥ͂ଔ೰̯ͦͥȃ߆ιΛ΅ঔࢥ͈࿒എ͞ૄ࠯ͬྖ

௷̳̭̦ͥ͂ஜ೹̦͂̈́ͥȂ߆ιΛ΅͈ఛٟ૙଻࢜ષ͈

̹͛ͅഞحसͬح̢̹߆ιΛ΅͈ഐဥ͉ܢఞ̧́ͥȃ

4.3ȁסఘಊளͥ͢ͅ΅λΫΞȜΏοϋ໨ၠ৘ࡑ ȁ଎8ͅסఘಊளͥ͢ͅ΅λΫΞȜΏοϋ໨ၠ৘ࡑ௡౾

͈ٽၞ଎ͬা̳ȃܖུഎ̈́௡౾ࢹ଼͉କ͈দࡑ௡౾͂൳

̲̜̦́ͥȂٸ໐̥͈ͣව෎̧̺̫ͬ́ͥཡ̪̹͛ͅۯ Ⴙ͈౯෎చॐ࣐̞ͬ̽̀ͥȃ૯ߗ౯෎΄ρΑယܕͅକদ ࡑ͈ાࣣ͂൳̲ΞΑΠΙλϋΨȜȪ΄ρΑ໐͉ੰݲȫͬ

වͦȂယܕ஠ఘͅסఘಊளͬවͦ̀৘ࡑ࣐̹ͬ̽ȃ΄ρ Αယܕ͉ͅ౯෎ऺͬے̧Ȃ֚໐౯෎ऺͬ୨ͤ৾̽̀۷ख़

ௗ̱̹͂ȃ΄ρΑယܕඤ͉ఱܨգ̜́ͥȃ

ȁထ๵৘ࡑ̱͂̀סఘಊளͬව̹ͦ΄ρΑယܕඤ́দࡑ

༌ͬ୭౾̵̴ͅΦΒσ̥ͣحգסఘಊளͬ໨ৣ̵̯̹͂

̭ͧȂ΅λΫΞȜΏοϋ໨ၠ͂ࣉ̢ͣͦͥฒ૗͈ΐͿΛ Π̦ږ෇̯̹ͦȪ଎9^Ȫa^ȫȫȃ

ȁ௽̞̀੗ͺση͈দࡑ༌ͅסఘಊள໨ၠͬ൚̀ͥ৘ࡑ

࣐̹ͬ̽ȃΑΗϋΡ΂έݻၗȂષၠգႁ͉କদࡑ͂൳̲

Fig.5^ȁComparison of eroded surface profiles

㪇㪅㪇 㪇㪅㪉 㪇㪅㪋 㪇㪅㪍 㪇㪅㪏 㪈㪅㪇 㪈㪅㪉 㪈㪅㪋 㪈㪅㪍

㪭㫆㫃㫌㫄㪼㩷㫃㫆㫊㫊㩷㫄㫄㪊

㪇㪅㪇 㪇㪅㪉 㪇㪅㪋 㪇㪅㪍 㪇㪅㪏 㪈㪅㪇 㪈㪅㪉 㪈㪅㪋 㪈㪅㪍

㪭㫆㫃㫌㫄㪼㩷㫃㫆㫊㫊㩷㫄㫄㪊

㪇 㪉㪇 㪋㪇 㪍㪇 㪏㪇 㪈㪇㪇

㪫㫀㫄㪼㩷㩷㪿

㪥㫀㩷㪘㫃㫃㫆㫐㩷㪎㪈㪏

㪫㫀㪄㪍㪘㫃㪄㪋㪭 㪪㪬㪪㪊㪇㪋 㪥㫀㩷㫇㫃㪸㫋㫀㫅㪾 㪘㪉㪏㪍 㪘㪾㩷㫇㫃㪸㫋㫀㫅㪾㩷㫎㫀㫋㪿 㪸㪻㪻㫀㫋㫀㫆㫅㩷㪸㪾㪼㫅㫋㫊

㪚㫉㩷㫇㫃㪸㫋㫀㫅㪾

㪇 㪈 㪉 㪊 㪋 㪌

㪫㫀㫄㪼㩷㩷㪿 㪚㪈㪈㪇㪇㪙㪛㪄㪟

㪘㫌㩷㫇㫃㪸㫋㫀㫅㪾 㪘㪾㩷㫇㫃㪸㫋㫀㫅㪾 㪘㪊㪌㪍

㪘㪈㪇㪌㪇㪙㪛㪄㪟㪈㪋

㪚㪊㪍㪇㪋

Fig.6^ȁVolume loss curves

㩷 㩷

㪇㪅㪇㪈 㪇㪅㪈 㪈 㪈㪇 㪈㪇㪇

㪈㪇㪇㪇 㪈㪇㪇

㪈㪇

㪜㫉㫆㫊㫀㫆㫅㩷㫉㪼㫊㫀㫊㫋㪸㫅㪺㪼㩷㩷㪿㪆㫄

㪭㫀㪺㫂㪼㫉㫊㩷㪿㪸㫉㪻㫅㪼㫊㫊㩷㩷㪟㫍 㪚㪈㪈㪇㪇㪙㪛㪄㪟 㪘㪊㪌㪍

㪘㪾㩷㫇㫃㪸㫋㫀㫅㪾 㪘㪈㪇㪌㪇㪙㪛㪄㪟㪈㪋

㪚㪊㪍㪇㪋

㪘㪉㪏㪍 㪥㫀㩷㫇㫃㪸㫋㫀㫅㪾

㪘㪾㩷㫇㫃㪸㫋㫀㫅㪾㩷㫎㫀㫋㪿 㪸㪻㪻㫀㫋㫀㫆㫅㩷㪸㪾㪼㫅㫋㫊 㪫㫀㪄㪍㪘㫃㪄㪋㪭 㪪㪬㪪㪊㪇㪋

㪥㫀㩷㪘㫃㫃㫆㫐㩷㪎㪈㪏

Fig.7ȁRelation between Hv and erosion resistance

㪄㪇㪅㪋㪇 㪄㪇㪅㪊㪇 㪄㪇㪅㪉㪇 㪄㪇㪅㪈㪇 㪇㪅㪇㪇 㪇㪅㪈㪇

㫄㫄 㪇㪅㪉㪇

㪇㪅㪇 㪉㪅㪇 㪋㪅㪇 㪍㪅㪇 㪏㪅㪇 㪈㪇㪅㪇 㪈㪉㪅㪇

㫄㫄

㫄㫄

㪄㪇㪅㪋㪇 㪄㪇㪅㪊㪇 㪄㪇㪅㪉㪇 㪄㪇㪅㪈㪇 㪇㪅㪇㪇 㪇㪅㪈㪇 㪇㪅㪉㪇

㪄㪇㪅㪋㪇 㪄㪇㪅㪊㪇 㪄㪇㪅㪉㪇 㪄㪇㪅㪈㪇 㪇㪅㪇㪇 㪇㪅㪈㪇 㪇㪅㪉㪇

㪇㪅㪇 㪉㪅㪇 㪋㪅㪇 㪍㪅㪇 㪏㪅㪇 㪈㪇㪅㪇 㪈㪉㪅㪇

㫄㫄

㫄㫄

(c) Silver plating (1h20m)

㪉㪅㪇 㪋㪅㪇 㪍㪅㪇 㪏㪅㪇 㪈㪇㪅㪇 㪈㪉㪅㪇

㫄㫄

㪇㪅㪇

̱͂Ȃئၠգႁ͉ఱܨգȪ΄ρΑယܕඤգȫ̜́ͥȃ৘

ࡑ͉࿩10໦ۼ৘ঔ̱̹ȃ΄ρΑယܕඤ̦ఱܨգ̜̹́ͥ

͛΅λΫΞȜΏοϋ໨ၠ̦দࡑ༌ͅ઩ඏ̱̹ࢃ͜΅λΫ ΞȜΏοϋ̦༲ٟ̱ඳ̩ܨ༺̦ॼͥેఠ͂̈́ͤȂ໨ၠ͈

઩ඏેޙͬમळͅ۷ख़̧̳̭͉̥̹ͥ͂́̈́̽Ȫ଎9 Ȫc^ȫȫȃ

ȁ଎10ͅ৘ࡑࢃ͈੗ͺσηদࡑ༌͈అੱેޙͬা̳ȃକ দࡑ͈̠̈́͢ςϋΈે͈ٟ૙͉͂։̈́ͤಎ؇໐ͅఅੱउ

̦ࡉͣͦȂ;΁ȜΗΐͿΛΠͥ͢ͅఅੱͅয̞̀ͥȃئ

ၠգႁ̦ఱܨգ̜́ͤ΅λΫΞȜΏοϋ̦༲ٟ̱ඳ̞͈

́Ȃ̭͈అੱ͉΅λΫΞȜΏοϋͤ͢ΐͿΛΠͥ͢ͅגޣ

̦ఱ̧̞͂ࣉ̢̦ͣͦͥȂમळ̞͉̾̀ͅࢵ̈́ͥ৘ࡑ̦ຈ Fig.8^ȁTest apparatus of cavitating liquid nitrogen jet

Fig.9^ȁCavitating liquid nitrogen jet Motor

Test chamber Plunger

pump

P

LN2 tank

Return line

Drain line

High pressure line Low pressure line

Open to Atmosphere

Vacuum insulation

Open to Atmosphere P

C LN2

M

Accumulator

Fig.10ȁEroded surfaces by cavitating liquid nitrogen jet

Nozzle Specimen

(a) Pretest of LN2 jet (b) Before the LN2 jet test (c) During the LN2 jet test

(a) Damaged surface of Al specimen (b) Expanded view

ါ̜́ͥȃུ৘ࡑ͉́סఘಊளಎͅ΅λΫΞȜΏοϋ໨ၠ

ͬอ୆̵̯Ȃদࡑ༌ͅ઩ඏ̵଼̯̭̱̹ͥ͂ࢗͅȃࣽࢃȂ סఘಊள͈́΅λΫΞȜΏοϋٟ૙দࡑͬ৘̵࡛̯̹ͥ͛

͉ͅȂئၠգႁͬحգ̱̀দࡑ༌ນ࿂̀ͅ΅λΫΞȜΏο ϋ̦༲ٟ̳ͥેޙͬैͤ੄̳࠿൦̦ຈါ̜́ͥȃ

ˑȅࠫ࡞

ȁυΉΛΠဥεϋίͅဥ̞ͣͦͥऺၳͬಎ૤ͅ΅λΫΞ ȜΏοϋ໨ၠ༹ٟͥ͢ͅ૙দࡑ࣐̞ͬȂ΅λΫΞȜΏο ϋٟ૙අ଻ͬ৾ං̱̹ȃͼϋΟνȜ΍͞ͼϋβρͅဥ̞

ͣͦͥऺၳ͉௙̲̀ఛٟ૙଻̦࿹̞ͦ̀ͥȃ༷֚Ȃ߆ι Λ΅ऺ͉਴̥̞̹ͣ͛ͅఛٟ૙଻͉೩̞̦Ȃഞحसͬح

̢̭ٟͥ͂ͤ͢ͅ૙೷ࢯ̦࿩10෼௩ح̱Ȃࣁഽͅచ̳ͥ

ఛٟ૙଻࢜͜ષ̳ͥȃ

ȁ̹͘Ȃޭ೩أ໨ၠ৘ࡑ௡౾ͬୋै̱̀סఘಊளͥ͢ͅ

΅λΫΞȜΏοϋ໨ၠ৘ࡑ࣐̹ͬ̽ȃסఘಊளಎ͈΅λ ΫΞȜΏοϋ໨ၠ͈อ୆ͬږ෇̱Ȃ໨ၠͬ൚̹̀দࡑ༌

ນ࿂͉ͅఅੱउ̦෇̹͛ͣͦȃٟ૙ͬૺ̵࣐̯ٟ̀૙අ

଻ͬ৾ං̳̹͉ͥ͛ͅࢵ̈́ͥ௡౾͈٨ၻ̦ຈါ̜̦́ͥȂ

ޭ೩أၠఘͥ͢ͅ΅λΫΞȜΏοϋٟ૙৘ࡑ̦৘࡛خෝ

̜̭̦́ͥ͂া̯̹ͦȃ

৫ৃ

ȁུࡄݪ͈দࡑ௡౾ͅ۾̱̀໛֔ఱڠ͈໚໐ਘষޗ਎ͅ

͉ତఉ̩͈੩࡞ͬೀ̧Ȃদࡑ༌ιΛ΅ঔࢥ൝ͅ۾̱̀Ժ

ࣞਝاڠ͈ࣞޘୃ࣐ঙȂࡼ਱၆ඃྶঙͅȂఉఱ̮̈́ފႁ

ͬೀ̧̱̹͘ȃ̭̭ۜͅ৫͈փͬນ̱̳͘ȃ

४ࣉ໲ࡃ

1ȫTsujimoto, Y., et al., Observations of oscillating cavi- tation of an inducer, ASME J. Fluids Eng., 119(1997), pp. 775-781.

2^ȫHattori, S., Ishikura, R. and Zhang, Q., Construction of data base on cavitation erosion and analyses of carbon steel data, Wear, 257, (2004), pp. 1023-1029.

3ȫ໚໐Ȇཤ୼ȄΟȜΗαȜᾼܖ̩̿ಚഘ̤͍͢๱ഘऺ

ၳ͈΅λΫΞȜΏοϋٟ૙೷ࢯ͈ٜଢ଼͂ౢளࣙΟȜΗ

͈͂๤ڛȄܥაAȄ74-738 (2008-2)Ȅpp. 248-253ȅ 4^ȫTSJ G 001:2011Ȅεϋί͈΅λΫΞȜΏοϋఅੱ͈ထ

௶͂ບثȄΗȜδܥ٫ފٛঐૻ(2011).

5^ȫASTM G134-95, Standard test method for erosion of solid materials by a cavitating liquid jet, Annual Book of ASTM Standards, Vol.03.02 (1997), pp. 537-548.

6ȫர५Ȇఈ5ྴȄࣞ௸କಎକ໨ၠ͈ͩͤ͘΅λΫΞȜΏ οϋܨ༺׋͈ࣞ௸ৢ૯۷ख़ȄܥაB^Ȅ59-562(1993-6)^Ȅ pp. 1919-19240.