(Karolo ea Kovar ho AluminaHlahisa kaWintrustek)

I. Kakaretso ea Kovar

Kovar ke motsoako oa tšepe oa nickel-cobalt-based expansion alloy eo tšobotsi ea eona e ka sehloohong e leng hore coefficient ea katoloso ea mocheso e ts'oanang le ea likhalase tse thata le lirafshoa (tse kang alumina) ho pholletsa le mocheso o itseng. Karolo ena e etsa hore e be thepa ea bohlokoa ea ho tiisa ka har'a liphutheloana tsa elektroniki, sefofane, lasers le liindasteri tse ling. Hangata e sebelisoa ho etsa lisebelisoa tsa tšepe bakeng sa ho tiisa hermetic ka khalase kapa lirafshoa.

Lebitso "4J" bakeng sa li-alloys tse nepahetseng tlas'a maemo a naha ea Chaena (GB) le emela li-alloys tse nang le litšobotsi tsa ho atolosa "ho atamela" (J) boleng bo itseng.

II. Tlhahlobo e Feletseng ea Lihlopha tse tharo tsa Kovar

Tloaelo: Kaofela ba bararo ba thehiloe ho Fe-Ni-Co 'me ba na le thepa ea ho atolosa e tšoanang le khalase e thata le lirafshoa. Li-curve tsa katoloso ea mocheso, mocheso oa Curie, le litšobotsi tsa mochini li fapana haholo ka lebaka la liphetoho tse nyane tsa sebopeho.

1. 4J29 (the most classic and widely used Kovar)

Sebopeho se Tloaelehileng:Fe-29Ni-17Co, e nang le litlatsetso tse nyane tsa likarolo tsa deoxidizing joalo ka manganese le silicon.

Litšobotsi tsa Katoloso: Katoloso e tloaelehileng ea khoele e tsamaellanang haholo le khalase ea sehlopha sa DM-308 molybdenum le 92-96% ea lirafshoa tsa alumina ho pholletsa le 20-450°C.

Lintlha tsa bohlokoa:

• Thempereichara ea curie: Hoo e ka bang 430°C (e lahleheloa ke thepa ea ferromagnetic ka holimo ho mocheso ona).

• Lisebelisuoa tse Bapisang: Li-ceramics tsa aluminium tse phahameng, likhalase tsa sehlopha sa molybdenum.

• Kalafo ea Bokaholimo: Ka tloaelo e hloka nickel kapa khauta ea khauta ho matlafatsa matla le ho thibela kutu.

• Lisebelisoa tsa mantlha: Li-microwave tubes, lasers, integrate circuit housings, li-relay tse tšepahalang haholo, lihokelo tse tiisitsoeng tsa aerospace.

2. 4J33 le 4J34 (Kovar e Ntlafetseng)

Li-alloys tsena ke mefuta e fapaneng e ntlafalitsoeng ho rarolla mefokolo ea 4J29 (joalo ka li-coefficients tse phahameng tsa mocheso o tlase), tse nang le mocheso o phahameng oa Curie.

Liphapang tsa Liqapi:

• 4J33: Fe-33Ni-14Co (reduced cobalt, increased nickel).

• 4J34: Fe-31Ni-15Co (composition intermediate between the two).

Litšobotsi tsa Katoloso:Mocheso oa kamore ho ea ho hoo e ka bang 300 ° C, coefficient ea katoloso e tlase hanyenyane ho feta 4J29, e fana ka ho lumellana hamolemo le likhalase tse itseng tse khethehileng kapa li-ceramics.

Molemo oa Bohlokoa—Mocheso o Phahameng oa Curie:

• 4J29: ~430°C

• 4J33: ~500°C

• 4J34: ~480°C

Bohlokoa:Mocheso o phahameng oa Curie o tiisa hore thepa e lula e se ea makenete ho mocheso o phahameng oa ts'ebetso, ho thibela ho kena-kenana le matla a khoheli ka lisebelisoa tse phahameng tsa maqhubu, tse nepahetseng haholo.

Kgetho ya kopo: E loketse ditikoloho tsa mocheso o hodimo kapa ditshebediso tse thata haholo, kapa tse kgethilweng ho itshetlehile ka diteko tsa katoloso ya curve ka lisebelisoa tse itseng tsa ho tiisa.

III. Melemo ea mantlha ea Brazing Kovar e nang le Ceramics ea Alumina

Ho tiisoa ha hermetic e tiileng ea khase ea Kovar le li-ceramics tsa alumina ka brazing ke theknoloji ea bohlokoa ho pakang ea sejoale-joale ea elektroniki, e nang le melemo e latelang:

1. Molemo o Ikhethang oa Katoloso ea Thermal (Molemo oa Motheo)

Ha ho pholile ho tloha ho brazing ho ea mocheso oa kamore, litekanyetso tse tšoanang tsa ho honyela ha lisebelisoa ka bobeli li fokotsa haholo khatello ea mocheso e setseng lenonyeletsong. Sena se atleha ho felisa ho phatloha ha ceramic le brazing seam fractures, ho fella ka ho tšepahala ho hoholo.

2. Ho Finyella Mathata a Maholo a Khase

Litefiso tsa ho lutla ha Helium lits'ebetsong tse holileng hangata li oela ka tlase ho 1 × 10⁻⁸ Pa·m³/s bakeng sa likarolo tse tiisitsoeng, ka katleho li arola mongobo o kantle le oksijene. Sena se kopana le litlhokahalo tse matla tsa ts'epo bakeng sa sepakapaka, sesole, le lits'ebetso tse ling tse batloang haholo.

3. Matla a Phahameng a Metjhini le Botšepehi ba Sebopeho

Kovar provides ts'ehetso e matla ea mochini le ho tiea, ha lirafshoa tsa alumina li fana ka ts'ehetso e ntle haholo le ho thatafala. Ho khabisa lisebelisoa tsena ho etsa hore ho be le mohaho o matla oa motsoako o nang le likarolo tse peli tse sireletsang le tse sebetsang.

4. Mekhoa ea Batho ba Holileng Le ho Tšepahala ho Holimo

Ho entsoe ketane e tsitsitseng ea ts'ebetso, e kenyelletsang metallization ea ceramic (molybdenum-manganese technique), nickel plating, kopano e nang le likarolo tsa Kovar, le vacuum / sireletso ea tikoloho. Mokhoa ona o laoloa haholo, o loketse tlhahiso ea bongata, 'me o hlahisa chai e ngata ka boleng bo tsitsitseng.

IV. Kakaretso ea Papiso le Likhothaletso tsa Khetho

Ⅴ. Qetello

Ka har'a lelapa la Kovar, 4J29 ke lisebelisoa tse tloaelehileng le tse khothalelitsoeng bakeng sa ho betla lirafshoa tse phahameng tsa alumina, ho fana ka tekanyo e ntle ea ts'ebetso, litšenyehelo le ho tšepahala. 4J33/34 ke ntlafatso ea ts'ebetso bakeng sa lits'ebetso tse itseng tse hlokang mocheso o moholo oa ts'ebetso kapa litšoaneleho tse matla tsa nonmagnetic.Ho chesoa ha Kovar ka lirafshoa tsa alumina, e tšehetsoeng ke ho bapisa ha bona ka ho atolosa mocheso, e fetohile tekanyetso ea indasteri ea ho paka ka hermetic ea likarolo tse phahameng tsa elektronike le tsa optoelectronic tse tšepahalang.