Ta yaya Silicon Carbide zai Inganta Ingancin Gyare-gyare?

1.Introduction

Abun da ke cikin sinadarin narkar da baƙin ƙarfe iri ɗaya ne, kuma tsarin narkewa ya bambanta, kuma kaddarorin baƙin ƙarfe da aka samu sun bambanta ƙwarai. A foundry rungumi dabi'u kamar narkakkar baƙin ƙarfe zafi fiye da kima, inoculation magani, canza cajin rabo, ƙara alama ko alloying abubuwa, da dai sauransu, don inganta metallurgical ingancin da simintin yi na simintin ƙarfe, kuma a lokaci guda ƙwarai inganta inji Properties da aikin sarrafawa. Ƙunƙarar wutar lantarki mai narkar da baƙin ƙarfe na iya sarrafa zafin zafin baƙin ƙarfe yadda yakamata, daidaita daidaiton sinadarai, rage asarar ƙonawa, kuma yana da ƙarancin sulfur da abun cikin phosphorus. Yana da fa'ida sosai don samar da baƙin ƙarfe mai ɗorewa, baƙin ƙarfe mai ƙyalli na vermicular da ƙarfe mai ƙarfi mai launin toka. Koyaya, ƙimar ƙarfe na narkar da baƙin ƙarfe da aka narkar da shi a cikin murhun wutar lantarki yana raguwa, kuma farin bakin yana da girma, kuma yana da sauƙi don samar da hoto mai tsananin sanyi. Kodayake ƙarfi da taurin sun ƙaru, ingancin ƙarfe na ƙarfe ƙarfe ba shi da yawa.

A cikin shekarun 1980, injiniyoyin Sinawa da suka je kasashen waje don yin karatu da karatu sun ga cewa an kara bakar abubuwa masu kama da gilashi a cikin tanderun wutar lantarki na ma’adanai na kasashen waje lokacin da aka narkar da su. Bayan bincike, sun gano cewa silicon carbide ne. Kamfanonin samar da albarkatun cikin gida na Jafananci sun kuma yi amfani da carbide silicon azaman ƙari a cikin adadi mai yawa na dogon lokaci. A cikin cupola ko tanderun wutar lantarki yana narkar da baƙin ƙarfe, fa'idodin ƙara wakilin yin siyar da SiC suna da yawa. Silicon carbide zuwa kashi abrasive sa da ƙarfe sa. Na farko yana da girma a cikin tsarki kuma yana da tsada, yayin da na ƙarshe yana da ƙima.

Carbide na silicon da aka kara a cikin tanderun yana canzawa zuwa carbon da silicon na baƙin ƙarfe. Isaya shine ƙara ƙimar carbon; ɗayan shine don ƙarfafa raguwar narkar da baƙin ƙarfe da rage girman tasirin cajin tsatsa. Haɗin carbide na siliki na iya hana haɓakar carbides, haɓaka adadin ferrite, sa tsarin ƙarfe ƙarfe mai yawa, inganta aikin sarrafawa da sanya farfaɗowar ƙasa tayi santsi. Haɓaka adadin kwallaye masu ƙima a kowane yanki na baƙin ƙarfe na nodular da haɓaka ƙimar spheroidization. Hakanan yana da tasiri mai kyau akan rage haɗe-haɗen da ba na ƙarfe ba da slag, kawar da ƙanƙantar da kai, da kawar da ramukan subcutaneous.

2. Matsayin Yin Rai

2.1 Ka'idar nucleation A cikin tsarin Fe-C eutectic, baƙin ƙarfe mai launin toka shine farkon lokacin eutectic saboda babban maƙasudin narkar da graphite yayin matakin ƙarfafawa na eutectic, kuma austenite ya faɗi ta hanyar graphite. Graphite mai kashi biyu + austenite co-girma da haɗin gwiwar da aka girka tare da kowane maƙallan graphite kamar yadda ake kiran clusters cute. Ƙididdigar giciye na submicroscopic, ɓoyayyen giraf ɗin da ba a narkar da su ba, wasu abubuwan narkar da sinadarin sulfides, oxides, carbides, barbashi nitride, da dai sauransu waɗanda ke cikin narkar da ƙarfe na ƙarfe na iya zama iri -iri. Babu wani muhimmin bambanci tsakanin ɓarna na baƙin ƙarfe na nodular da ƙirar baƙin ƙarfe mai launin toka, sai dai an ƙara sinadarin magnesium oxide da sulfides a cikin ainihin kayan.
       
Hazo na graphite a cikin narkakken baƙin ƙarfe dole ne ya sami matakai biyu: nucleation da girma. Akwai hanyoyi guda biyu na keɓancewar graphite: daidaituwa mai kama da juna. Halittar mahaɗan mahaifa kuma ana kiranta nucleation na kwatsam. Akwai adadi mai yawa na sinadarin carbon a cikin narkakken ƙarfe wanda ya zarce ƙima mai girman ƙima mai ƙyalli, kuma ƙungiyoyin atom ɗin carbon da aka shirya cikin tsari cikin ɗan gajeren zango na iya zama madaidaicin madaidaicin kristal. Gwaje -gwajen sun nuna cewa matakin supercooling na crystal nuclei nuclei yana da girma ƙwarai, kuma dole ne a yi amfani da ginshiƙi iri iri daban -daban azaman wakilin nucleating na graphite a narkakken ƙarfe. Akwai adadi mai yawa na barbashi na baƙin ƙarfe da aka narkar, kuma akwai maki miliyan 5 na oxidized a cikin kowane 1cm3 na baƙin ƙarfe. Waɗannan barbashi kawai waɗanda ke da wata alaƙa tare da sigogin lattice da matakan graphite na iya zama ginshiƙan ginshiƙan ginshiƙi. Siffar sifa ta dangantakar da ta dace da lattice ana kiran ta da matakin rashin daidaituwa na jirgin sama. Tabbas, kawai lokacin da rashin daidaiton jirgin lattice ya yi ƙanƙanta ne atom ɗin carbon ɗin zai iya dacewa da ginshiƙan ginshiƙi. Idan abubuwan da ke tattare da jujjuyawar sunada sinadarin carbon, to matakin rashin jituwarsu shine sifili, kuma irin wannan yanayin nucleation shine mafi kyau.

Ƙarfin ciki na silicon carbide wanda ya lalace cikin carbon da silicon a cikin narkakken ƙarfe ya fi carbon da silicon da ke cikin baƙin ƙarfe kanta. Si wanda ke cikin baƙin ƙarfe da kansa yana narkar da shi a cikin austenite, kuma carbon a cikin narkakken baƙin ƙarfe na baƙin ƙarfe na baƙin ƙarfe yana cikin baƙin ƙarfe. An samar da ginshiƙan graphite a cikin ruwa, wasu daga cikinsu waɗanda ba a riga an saukar da su a cikin austenite ba. Sabili da haka, ƙari na carbide na silicon yana da tasirin deoxidation mai kyau.

• Si + O2 → SiO2
• (1) MgO +SiO2 → MgO ∙ SiO2
• (2) 2MgO +2SiO2→ 2MgO∙2SiO2
• (3) Enstatite abun da ke ciki MgO ∙ SiO2 da forsterite abun da ke ciki 2MgO ∙ 2SiO2 suna da babban matakin rashin daidaituwa tare da graphite (001), wanda yana da wahalar amfani da shi azaman tushe don ƙirar gira. Bayan an bi da shi da narkakken ƙarfe mai ɗauke da Ca, Ba, Sr, Al da ferrosilicon, MgO ∙ SiO2 + X → XO ∙ SiO2 + Mg
• (4) (2MgO ∙ 2SiO2) + 3X + 6Al → 3 (XO ∙ Al2O3 ∙ 2SiO2) + 8Mg
• (5) Inda X —— Ca, Ba, Sr.

Samfuran masu amsawa XO ∙ SiO2 da XO ∙ Al2O3 ∙ SiO na iya ƙirƙirar lu'ulu'u masu fuska akan MgO ∙ SiO2 da 2MgO ∙ 2SiO2 substrates. Saboda ƙarancin rashin daidaituwa tsakanin hoto da XO ∙ SiO2 da XO ∙ Al2O3 ∙ SiO2, yana da kyau ga ƙirar hoto. Kyakkyawan jadawali. Zai iya inganta aikin sarrafawa da haɓaka kaddarorin injin.

2.2 Pre-inoculation na rashin daidaiton hoto:

Gabaɗaya, ana faɗaɗa ikon juzu'in mahaifa daban -daban ta hanyar inoculation, da kuma rawar da ake samu a cikin narkar da baƙin ƙarfe:

• Rom Haɓaka yawan hazo na C a cikin matakin ƙarfafawa na eutectic da ƙirƙirar hoto don haɓaka zayyanawa;
• Rage matakin narkar da baƙin ƙarfe supercooling kuma rage halayen farin baki;
• ③ Ƙara yawan gungu -gungu na eutectic a cikin baƙin ƙarfe na ƙarfe mai launin toka ko ƙara adadin ƙwallon ƙira a cikin baƙin ƙarfe.

Ana ƙara SiC yayin ƙarar cajin. Silicon carbide yana da wurin narkewa na 2700 ° C kuma baya narkewa cikin baƙin ƙarfe. Yana narkewa ne kawai a cikin narkakkar baƙin ƙarfe bisa ga tsarin dabara mai zuwa.
SiC+Fe → FeSi+C (graphite maras daidaituwa)

(6) A cikin dabara, Si a SiC an haɗa shi da Fe, ragowar C kuma shine ma'aunin ma'aunin ma'auni, wanda ke aiki azaman jigon ruwan sama. Graphite marasa daidaituwa yana sa C a cikin narkakken ƙarfe ba a rarraba shi ba, kuma ɓangaren C na gida ya yi yawa, kuma "kololuwar carbon" zai bayyana a cikin ƙananan wuraren. Wannan sabon ginshiƙi yana da babban aiki, kuma rashin daidaituwarsa da carbon ba komai, don haka yana da sauƙin sha carbon a cikin narkakken baƙin ƙarfe, kuma tasirin inoculation yana da matuƙar fifiko. Ana iya ganin cewa carbide na silicon shine irin wannan wakili na tushen siliki.

Ana ƙara carbide na siliki yayin ƙamshin baƙin ƙarfe. Don baƙin ƙarfe na ƙarfe, pre-incubation of non-equibibrium graphite zai haifar da adadi mai yawa na gungun eutectic da ƙara yawan zafin jiki na girma (rage rashin jin daɗin dangi), wanda ke dacewa da samuwar nau'in A graphite; adadin guntun gwal yana ƙaruwa, yana yin flakes Graphite yana da kyau, wanda ke inganta matakin zanawa da rage ɗabi'ar farin baki, ta hakan yana haɓaka kaddarorin injin. Don ƙirar ƙarfe na spheroidal, ƙaruwar murhun murhun yana ƙaruwa da adadin maƙallan graphite kuma ana iya inganta ƙimar spheroidization.

2.3 Kawar da baƙin ƙarfe na baƙin ƙarfe mai launin toka. C-type da F-type graphite na farko an kafa su a cikin lokacin ruwa. Saboda tsarin ci gaba ba ya tsoma baki ta hanyar austenite, a ƙarƙashin yanayi na yau da kullun, yana da sauƙi girma cikin manyan flakes da ƙarancin reshe C-type Graphite: Lokacin da aka sanya sanyaya mai katanga da sauri-sauri, graphite zai yi reshe ya girma cikin tauraro- Graphite mai siffar F.
Graphite flake da aka girma a cikin matakin ƙarfafawa na eutectic yana haifar da A, B, E, D jadawalin siffofi daban -daban da rarrabuwa daban -daban a ƙarƙashin abubuwan haɗin sinadarai daban -daban da yanayin sanyi daban -daban.

Rubuta A graphite an ƙirƙira shi a cikin tarin eutectic tare da ƙaramin sanyi da ƙarfin nucleation, kuma an rarraba shi daidai gwargwado. Daga cikin pearlite flake mai kyau, mafi ƙanƙantar tsayin graphite, mafi girman ƙarfin tensile, wanda ya dace da kayan aikin injiniya da simintin injin daban -daban.

Nau'in D graphite shine maki da takaddar-kamar ginshiƙan interdendritic tare da rarraba ba tare da jagora ba. D-type graphite simintin baƙin ƙarfe yana da babban abun ciki na ferrite kuma kayan aikin injin sa suna shafar. Koyaya, nau'in baƙin ƙarfe na nau'in D yana da dendrites austenite da yawa, graphite gajere ne kuma mai lankwasa, kuma ƙungiyar eutectic tana cikin nau'in pellets. Sabili da haka, idan aka kwatanta da irin wannan matrix A-type graphite cast iron, yana ɗaukar samun ƙarfi mafi girma.

Nau'in E graphite wani nau'in graphite flake ne wanda ya fi guntu fiye da Nau'in A. Kamar nau'in nau'in nau'in D, yana tsakanin dendrites kuma ana kiransa gaba ɗaya a matsayin graphite dendritic. E tawada yana da sauƙi a samar da shi a cikin baƙin ƙarfe tare da ƙarancin carbon daidai (babban matakin hypoeutectic) da dendrites masu arziki na austenite. A wannan lokacin, gungu-gungu na eutectic da dendrites suna haɓaka ƙetare. Saboda adadin ruwan baƙin ƙarfe na interdendritic eutectic ƙarfe ƙarami ne, preifitated eutectic graphite kawai yana rarraba tare da jagorancin dendrites, wanda yana da bayyananniyar hanya. Matsayin undercooling forming E-type graphite ya fi na A-type graphite da ƙasa da na D-type graphite, kuma kaurinsa da tsayinsa suna tsakanin A da D-graphite. Nau'in harafin E ba ya cikin babban hoto mai sanyi, kuma galibi yana tare da nau'in graphite D. Rarraba shugabanci na nau'in E-graphite tsakanin dendrites yana ba da sauƙi ga simintin ƙarfe ya zama mai karyewa kuma ya karye a cikin ƙungiya tare da tsarin tsara hoto a ƙarƙashin ƙaramin ƙarfi na waje. Sabili da haka, E-type graphite yana bayyana, kuma ana iya karya sasannun ƙananan simintin hannu, kuma ƙarfin simintin ya ragu sosai. Yayin da abun cikin carbon ke ƙaruwa, ƙimar sanyayawar da ake buƙata don samar da madaidaicin ginshiƙan interdendritic yana ƙaruwa, kuma yuwuwar samar da ginshiƙan interdendritic yana raguwa. Babban matakin zafi fiye da kima na narkewa da adana zafi na dogon lokaci zai haɓaka matakin rashin jin daɗi, ta haka yana haɓaka ƙimar dendrites, yana sa dendrites ya fi tsayi da samun madaidaicin alkibla. Lokacin da ake amfani da SiC don pre-incubate baƙin ƙarfe, ƙusoshin babban austenite yana raguwa a lokaci guda, kuma ana lura da ɗan gajeren dendrites a wannan lokacin. Yana kawar da ginshiƙan tsari na nau'in E-graphite.

2.4 Inganta Injin Karfe

Don ƙarar baƙin ƙarfe na spheroidal, a cikin adadin adadin wakilin spheroidizing, yin rigakafi tare da carbide na silicon, ƙimar ƙarshe na magnesium ya fi girma. Don narkakken baƙin ƙarfe da aka ƙera tare da carbide na silicon, idan an kiyaye adadin ragowar magnesium a cikin simintin gyare -gyare daidai gwargwado, za a iya rage adadin wakilin da ake ƙarawa da kashi 10%, kuma ana rage raunin farin bakin ƙarfe na baƙin ƙarfe.

Silicon carbide a cikin makera mai narkewa, ban da carbon da silicon a cikin narkakken baƙin ƙarfe da aka nuna a cikin dabara (1), da deoxidation reaction na formula (2) da (3) kuma ana aiwatar da su. Idan SiC da aka ƙara yana kusa da bangon tanderu, SiO2 da aka samar zai saka a bangon tanderu kuma zai ƙara kaurin bangon tanderu. A ƙarƙashin babban zafin jiki na ƙamshi, SiO2 za ta sha ruwan decarburization na tsari (4) da kuma ɓarna na dabara (5) da (6).

• (7) 3SiC +2Fe2O3 = 3SiO2 +4Fe +3C
• (8) C + FeO → Fe + CO ↑
• (9) (SiO2) + 2C = [Si] + 2CO (yanayin gas)
• (10) SiO2 + FeO → FeO · SiO2 (slag)
• (11) Al2O3 + SiO2 → Al2O3 · SiO2 (slag)

Sakamakon deoxidizing na silicon carbide yana sa samfurin deoxidized yana da jerin halayen ƙarfe a cikin narkakken ƙarfe, yana rage illolin oxides a cikin gurɓataccen cajin, kuma yana tsarkake ƙarfe mai narkewa yadda yakamata.

2.5 Yadda ake Amfani da Carbide Silicon

Tsarkin carbide na silicon ƙarfe yana tsakanin 88% zuwa 90%, kuma dole ne a fara cire ƙazantar da farko lokacin lissafin ƙimar carbon da silicon. Dangane da tsarin kwayoyin silicon carbide, yana da sauƙi don samun: Haɓaka Carbon: C = C/(C + Si) = 12/(12 + 28) = 30% (12) Ƙarin siliki: Si = Si/(C + Si) = 28 / (12 + 28) = 70% (13) Adadin siliki carbide da aka ƙara yawanci shine 0.8% -1.0% na adadin baƙin ƙarfe. Hanyar ƙara carbide silicon shine: narkar da baƙin ƙarfe a cikin tanderun wutar lantarki. Lokacin da murfin ya narkar da 1/3 na cajin, ƙara shi zuwa tsakiyar murfin, yi ƙoƙarin kada ku taɓa bangon murhu, sannan ku ci gaba da ƙara cajin ƙanshin. A cikin cupola yana narkar da baƙin ƙarfe, ana iya haɗe carbide na siliki tare da girman barbashi na 1-5mm tare da adadin ciminti ko wasu manne, kuma ana ƙara ruwa don yin taro. Bayan bushewa a cikin rana mai zafi, ana iya amfani dashi a cikin tanderun gwargwadon tsari.

3.Ga Gabatarwa

A cikin shekaru 20 da suka gabata, ko mota ce, kasuwanci ko motar iyali, rage nauyin abin hawa koyaushe shine yanayin ci gaban bincike da haɓaka motoci. A cikin koma bayan kasuwa na rikicin kuɗi, China Northern Corporation ta ɓullo da yanayin kuma ta fitar da manyan motocin dakon kaya zuwa Arewacin Amurka, daidai gwargwadon nauyin manyan motocin dakon kaya. Aikace-aikacen baƙin ƙarfe mai launin toka mai kauri, baƙin ƙarfe mai ɗamara da baƙin ƙarfe mai ƙyalƙyali, ƙarfe mai kauri mai kauri da Aubrey ductile baƙin ƙarfe, yana gabatar da buƙatu mafi girma akan ingancin ƙarfe na ƙarfe.

Yin rigakafin inoculation na silicon carbide yana da kyakkyawan tasiri akan haɓaka ƙimar ƙarfe na ƙarfe. Kwararren masanin harshe Li Chuanshi ya rubuta wata kasida cewa bayan da aka kara wakili na riga -kafi a cikin narkakken baƙin ƙarfe, ana iya lura da sakamako biyu: ɗaya shine ƙara ƙimar carbon; ɗayan shine canza yanayin ƙarfe na narkakken ƙarfe, wanda ke haɓaka haɓakawa.

A shekara ta 1978, BC Godsell na Ƙasar Ingila ya wallafa sakamakon bincikensa a kan ƙirar baƙin ƙarfe. Tun daga wannan lokacin, binciken gwaji kan tsarin yin riga -kafi bai katse ba, kuma tsarin yanzu ya yi girma sosai. Don baƙin ƙarfe mai launin toka, silicon carbide inoculation pretreatment na iya rage matakin rashin jin daɗi da rage ɗabi'ar farin baki; haɓaka ginshiƙi na hoto, inganta haɓaka nau'in A-type, rage ko hana samar da nau'in B, E-type da D-type graphite, da ƙara adadin gungu na eutectic. Graphite mai kyau; don ƙirar ƙarfe na spheroidal graphite, ƙirar allurar carbide silicon yana haɓaka haɓakar adadin kwallaye a cikin simintin ƙarfe, ƙimar spheroidization, da zagaye na ƙwallan graphite.

Amfani da carbide na siliki na iya ƙarfafa deoxidation da rage tasirin baƙin ƙarfe oxide, sa tsarin ƙarfe ya zama ƙarami da haɓaka santsi na farfaɗo. Yin amfani da carbide na siliki na iya tsawaita rayuwar bangon makera ba tare da ƙara yawan baƙin ƙarfe da aluminum ba.

Da fatan za a adana tushe da adireshin wannan labarin don sake bugawa:Ta yaya Silicon Carbide zai Inganta Ingancin Gyare-gyare?

Minghe Kamfanin 'Yan Wasa Masu Mutu aka sadaukar domin tsirar da samar da inganci da kuma high yi Gyare sassa (karfe mutu simintin sassa Range yafi hada da Thin-Wall Mutu Wasa,Hot Chamber Mutu Wasa,Cold Chamber Mutu Wasa), Zagaye Sabis (Mutuwar 'Yan Wasa,CNC machining,Motsa Motsa, Jiyya na sama) .Adadin al'ada Aluminium ya mutu, magnesium ko Zamak / zinc mutu simintin gyare-gyare da sauran buƙatun simintin maraba don tuntube mu.

Karkashin kulawar ISO9001 da TS 16949, Ana aiwatar da dukkan matakai ta hanyar daruruwan injunan jefa simintin da suka mutu, injunan axis 5, da sauran kayan aiki, tun daga masu fashewa zuwa na’urar Ultra Sonic masu wanki.Minghe ba kawai tana da kayan aiki na zamani ba amma kuma tana da kwararru ƙungiyar ƙwararrun injiniyoyi, masu aiki da sufetoci don tabbatar da ƙirar abokin ciniki ta zama gaskiya.

Manufactureran kwangilar masana'antar mutu. Abubuwan haɓakawa sun haɗa da sassan sanyi na sassan mutuɗar aluminum daga 0.15 lbs. zuwa 6 lbs., saurin canje-canje da aka saita, da aikin inji. Sabis-ƙarin ayyuka sun haɗa da gogewa, faɗakarwa, lalatawa, fashewar harbi, zane, zane, rufi, haɗuwa, da kayan aiki. Abubuwan da aka yi aiki tare sun haɗa da allo irin su 360, 380, 383, da 413.

Zinc ya mutu don jefa ƙirar ƙira / sabis na injiniya tare. Custom manufacturer na daidaici tutiya mutu simintin gyaran kafa. Castananan 'yan simintin gyare-gyare, pressurean ƙwanƙwasa masu juzu'in juzu'in simintin gyare-gyaren juzu'ai, ƙera simintin gyare-gyare na al'ada, ɓangaren mutu da' yan wasa masu mutuwa masu zaman kansu da ƙofar da aka hatimce za a iya ƙera su. Za'a iya kerarrar 'yan simintin a tsayi da faɗi har zuwa 24 a ciki. A cikin +/- 0.0005 a cikin. Haƙuri.  

ISO 9001: 2015 bokan masana'anta ta mutu magnesium, Abubuwan haɓaka sun haɗa da matsin lamba na magnesium mai matsi mai yawa har zuwa tan 200 mai ɗumi mai zafi & 3000 ton mai sanyi, ƙirar kayan aiki, gogewa, gyare-gyaren, inji, foda & zanen ruwa, cikakken QA tare da damar CMM , taro, marufi & isarwa.

ITAF16949 bokan. Servicearin Sabis ɗin Gyare Hadawa zuba jari,yashi,Kushin nauyi, Stauren ɓoye ɓoye,Siffar Centrifugal,Cast Vacuum,Dindindin Mould Gyare, .Hanyoyin iyawa sun hada da EDI, taimakon injiniya, ingantaccen samfuri da aiki na sakandare.

Fitar Masana'antu Abubuwan Nazarin sassa don: Motoci, Bikes, Jirgin sama, kayan kiɗa, Jirgin ruwa, Na'urorin hangen nesa, na'urori masu auna sigina, na'urori masu auna sigina, Na'urori, Kayan lantarki, ,unshi, Clocks, Inji, Injiniya, Kayan Kaya, Kayan Jiki, Jigs, Telecom, Haske, Kayan aikin likita, Na'urar daukar hoto, Robobi, Sassaka, kayan sauti, kayan wasanni, Kayan aiki, Kayan wasa da ƙari. 

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By Minghe Mutu Wasa Wasa | Categories: Labarai masu Taimakawa |Material Tags: Gyare Aluminum, Zinc Gyare, Fitar Magnesium, Castan Wasanni, Bakin Karfe Cast, Fitar tagulla,Gyare Tagulla,Fitar Bidiyo,Tarihin Kamfanin,Aluminum Mutu Gyare | Comments Off