Izakhiwo ze-Tungsten Metal Powder

Ukusebenza kwe-tungsten powder kunomthelela omkhulu ekusebenzeni kokucubungula kanye nekhwalithi yemikhiqizo elandelayo. Ngakho-ke, inkambu ye-hard alloy kanye nenkundla yokucubungula impahla ye-tungsten ibeke phambili izidingo ezihambisanayo zokuhlanzeka kwamakhemikhali kanye nezakhiwo ezibonakalayo ze-tungsten powder eluhlaza, ikakhulukazi izidingo zezakhiwo ezibonakalayo ziya ngokuya zikhuphuka. 

Ukuhlanzeka kwamakhemikhali

Lapho kukhiqizwa imikhiqizo kasimende ye-carbide ne-tungsten, ukuhlanzeka kwamakhemikhali we-tungsten powder kuyadingeka ukuthi kube phezulu. Izinto ezisele zokungcola ku-tungsten powder zinomthelela ekusebenzeni kokucubungula nokusebenza kwesevisi yemikhiqizo. Ithonya liyinkimbinkimbi kakhulu, kanti amanye ayingozi futhi amanye anenzuzo. Ucwaningo lwamanje lubonisa ukuthi i-Ca, Mg, P, As, Si, S, Fe, Ni, Cu, Al, ne-Mo inganciphisa amandla e-alloy, kuyilapho i-K ne-Na ikhuthaza ukukhula kwezinhlamvu ze-WC. Ngakolunye uhlangothi, i-V ne-Cr ivimbela ukukhula kwezinhlamvu. Uma okuqukethwe kwe-Mo ku-WO kudlula u-0.5%, kuzobangela ukwehla kwamandla e-flexural we-alloy. Ezinhlotsheni eziningi ze-tungsten powder ezikhiqizwayo njengamanje, okuqukethwe kokungcola okusalela kwensimbi (ngaphandle kwalokho okwengezwe njengezithasiselo) kuphakathi kwezingxenye ezimbalwa ezinkulungwaneni eziyishumi kuya ezingxenyeni ezimbalwa ezinkulungwaneni eziyikhulu. 

I-oksijeni eku-tungsten powder ingasabela ne-carbides, imunce ikhabhoni kuma-carbides futhi ibangele ukubola kwe-carbide enosimende. Lapho i-alloy ikhishwa kakhulu, isigaba sika-γ siyavela, okwenza i-alloy ibe brittle. Igesi ekhishwe ekuphenduleni ikhulisa i-porosity ye-alloy futhi inciphisa amandla ayo. Kuye ngezinqubo ezahlukene zokunciphisa kanye nemishini, okuqukethwe komoya-mpilo ku-tungsten powder ngokuvamile kuphakathi kuka-0.05% no-0.5%, futhi kuyanda ngokuncipha kosayizi wezinhlayiyana ze-tungsten kanye nokwanda kwendawo ethile. Ngakho-ke, isidingo sokuqukethwe komoyampilo kumpushana we-tungsten ocolisekile kufanele sikhululeke ngendlela efanele. Izidingo zokuhlanzeka kwamakhemikhali ze-tungsten powder ziboniswa kuThebula 4-1, futhi izidingo zokuqukethwe kwe-oxygen ziboniswa kuThebula 4-2.

Izakhi zokungcola ku-tungsten powder zingase zivele ezintweni ezingavuthiwe noma zethulwe phakathi nenqubo yokukhiqiza. Ngakho-ke, ukuvimbela ukungcoliswa kwezinto ngesikhathi senqubo kubaluleke kakhulu. Isibonelo, ekukhiqizeni i-tungsten powder kusetshenziswa i-APT njengento eluhlaza, izinto ezisetshenziswayo zithintana ngqo nesithando somlilo, amashubhu esithandweni somlilo sokunciphisa, nama-crucibles, okuholela ekwandeni kokuqukethwe kokungcola okufana ne-Fe, Ni, Cr, ne-Si, kanye nokuncipha kokuhlanzeka kwamakhemikhali. Uma okuqukethwe kwabo kufinyelela izinga elithile noma kuhlanganiswa usayizi owanele, kungase kube imithombo yokukhubazeka ukuze kucutshungulwe noma kusetshenziswe okulandelayo. Ngakho-ke, ukuqinisekisa ukuhlanzeka kwe-tungsten powder, ngaphezu kokulawula ngokuqinile ikhwalithi ye-APT yempahla eluhlaza, kubaluleke kakhulu ukuvimbela ukungcola phakathi nenqubo. 

2. Izakhiwo Zomzimba

Izici ezingokoqobo ze-metallic tungsten powder ikakhulukazi zifaka phakathi usayizi wezinhlayiyana ezimaphakathi, ukusatshalaliswa kosayizi wezinhlayiyana, idigri yokuhlanganisa izinhlayiyana, i-particle morphology, indawo ethile engaphezulu, ukuminyana ngobuningi, ukuminyana okuhlanganisiwe, nezinga lokugeleza kweHholo, njll. 

(Isilinganiso sosayizi wezinhlayiyana nokusabalalisa usayizi wezinhlayiyana)

Kungakhathaliseki ukuthi iyimikhiqizo ye-carbide enosimende noma ye-tungsten, kunezidingo eziqinile zesilinganiso sosayizi wezinhlayiyana nokusabalalisa usayizi wezinhlayiyana ze-tungsten powder. Emkhakheni we-carbide enosimende, usayizi wezinhlayiyana kanye nokusabalalisa usayizi wezinhlayiyana ze-W powder kuthinta ngokuqondile usayizi wezinhlayiyana nokusabalalisa usayizi wezinhlayiyana we-WC powder ekhiqizwayo. Ubukhulu bezinhlayiyana ze-WC powder buphinde bube nomthelela ekusebenzeni kwemikhiqizo ye-carbide enosimende. 

Ucwaningo luthole ukuthi izakhiwo ze-WC powder zikhawulelwe yilezo ze-W powder. Ngemuva kokuthi i-W powder ikhishwe nge-carbonized ukuze yakhe i-WC, usayizi wezinhlayiyana uba noshintsho oluncane. Ukuze kukhiqizwe impushana ye-WC yosayizi wezinhlayiyana ezimahhadlahhadla, eziphakathi nendawo nezicolekile, i-powder engu-W emahhadla, ephakathi nendawo necolekileyo idinga ukusetshenziswa. I-Uneven W powder carbonization iphumela ku-WC powder engalingani. Izinguquko kusayizi wezinhlayiyana zempushana ngemva kokwenziwa kwe-carbonization ye-powder emahhadlahhadla, ephakathi nendawo kanye necolekileyo iboniswa kuThebula 4-3.

Izidingo zosayizi wezinhlayiyana ze-tungsten powder ziyahlukahluka phakathi kwabasebenzisi abahlukene. Ngenkambu ye-alloy eqinile, ngezinhlobo ezahlukene zama-alloys aqinile asetshenziselwa izinhloso ezahlukene, ngenxa yobukhulu bezinhlayiya ezihlukene ze-WC powder esetshenzisiwe, kunezidingo ezihlukene zesayizi wezinhlayiyana ezimaphakathi kanye nokwakheka kosayizi wezinhlayiyana ze-W powder eluhlaza. Wonke amathuluzi okusika adinga i-W powder kanye ne-WC powder ukuze abe nosayizi wezinhlayiyana ezinhle kanye nokusabalalisa usayizi wezinhlayiyana ezincane. Amathuluzi omthelela adinga ukuthi i-W powder kanye ne-WC powder ukuthi zibe mahhadla, nokusabalalisa usayizi wezinhlayiyana ezibanzi. Isilinganiso sikasayizi wezinhlayiyana ezisetshenziselwa ukulungisa i-WC engamahhadla-grained ngu-25.8 μm. Ukusabalalisa usayizi wezinhlayiyana ezimele we-W powder kuboniswa kuMfanekiso 4-1.

Ngokucubungula impahla ye-tungsten, isilinganiso sosayizi wezinhlayiyana kanye nokusabalalisa usayizi wezinhlayiyana ze-tungsten powder kunomthelela ekusebenzeni ngokucindezelayo kwemikhiqizo elandelayo, ukuminyana komzimba oluhlaza (owaziwa nangokuthi umzimba ocindezelwe), kanye nokusebenza kwe-sintering. Usayizi wezinhlayiyana zempushana ezincane kanye nokuma okuyinkimbinkimbi kuzoholela ekubambisaneni okukhulu phakathi kwezinhlayiya, okuholela ekwehleni kokuminyana komzimba oluhlaza. Ukuncipha kokusabalalisa usayizi wezinhlayiyana, izinhlayiya zihlelwa ngokukhululekile. Ukusatshalaliswa kosayizi wezinhlayiyana okubanzi, noma ngisho nezimpushana ezixutshwayo zosayizi abahlukene bezinhlayiyana ezimaphakathi, zingafinyelela ukuhlelwa okungcono kwezinhlayiyana futhi zithole amandla aphezulu omzimba aluhlaza. Emkhakheni wokucubungula impahla ye-tungsten, isilinganiso sosayizi wezinhlayiyana ze-tungsten powder ngokuvamile sidingeka ukuba sibe phakathi kwebanga lika-2 kuya ku-6 μm. 

Kunezindlela eziningi zokunquma usayizi wezinhlayiyana zempushana kanye nokusabalalisa usayizi wezinhlayiyana. Imishini kaFischer kanye ne-laser particle size analyzer asetshenziswa kakhulu ku-tungsten powder. Kodwa-ke, ngenxa yezimiso ezihlukene zalezi zindlela ezimbili zokulinganisa, amanani alinganisiwe atholakala kumpushana ofanayo angase ahluke. Ngakho-ke, usayizi wezinhlayiyana ze-tungsten powder ngokuvamile kufanele kushiwo njengosayizi wezinhlayiyana ovamile we-Fischers noma usayizi wezinhlayiyana omaphakathi we-laser. Ukwengeza, kufanele kuqashelwe ukuthi "isimo esinikeziwe" i-tungsten powder ngokuvamile inamazinga ahlukahlukene e-agglomeration, ahlobene nezimo zokukhiqiza. Isilinganiso sosayizi wezinhlayiyana ze-tungsten powder elinganiswa kusetshenziswa amasampula anjalo angase ahluke kusayizi wezinhlayiyana zangempela zempushana. Isibonelo, usayizi wezinhlayiyana zempushana ethile ye-tungsten ebuthuntu "esimeni esihlinzekiwe" ngu-1-2 μm, futhi ngemva kokukhishwa kwe-depolymerization nokuhlakazwa, inani lehla liye ku-0.4-0.5 μm. Ngempushana ye-tungsten enosayizi bezinhlayiyana ebangeni lika-1-10 μm, ezimweni eziningi, ukukala usayizi wezinhlayiyana "zesimo esinikeziwe" kungahlangabezana nezidingo zokukhiqiza. Ku-submicron tungsten powder kanye nempushana ye-tungsten eqinile, ukuze kuphawulwe ngokunembe kakhudlwana usayizi wezinhlayiya, amasampula "esimo sokugaya" kufanele asetshenziselwe usayizi wezinhlayiyana omaphakathi nokuhlolwa kosayizi wezinhlayiyana. 

TUkusabalalisa usayizi wezinhlayiyana ze-tungsten powder kuhlobene nosayizi wezinhlayiyana zayo. Ngokuvamile, ubukhulu bezinhlayiyana ezimaphakathi ze-tungsten powder, buba banzi ukusatshalaliswa kosayizi wezinhlayiyana. Ngosayizi wezinhlayiyana ezinikeziwe, ekukhiqizeni, izindlela ezinjengokusebenzisa i-hydrogen emanzi noma ukwengeza izinhlanganisela zensimbi ye-alkali ku-tungsten oxide zingenza usayizi wezinhlayiyana zibe mkhulu futhi zilawule ububanzi bokusabalalisa usayizi wezinhlayiyana kancane kakhulu. Ukunqunywa kokusatshalaliswa kosayizi wezinhlayiyana kuvame ukwenziwa kusetshenziswa amasampula "wesimo esiphansi". 

Isilinganiso sezinhlayiyana ze-tungsten powder ngokuvamile zivezwa ububanzi bayo (ngama-micrometers). Kodwa-ke, ekusebenzeni kokukhiqiza, eminye imiqondo ye-semi-quantitative ivame ukusetshenziswa. Izigaba ezijwayelekile zihlanganisa: 

Izinhlayiya ezimahhadla: Isilinganiso sikasayizi wezinhlayiyana > 30 μm; 

30 μm; 

Izinhlayiya ezimahhadla: Isilinganiso sikasayizi wezinhlayiyana 10 kuya ku-30 μm; 

Izinhlayiya ezinosayizi omaphakathi: Isilinganiso sikasayizi wezinhlayiyana 3 kuya ku-10 μm; 

Izinhlayiya ezinhle: Isilinganiso sosayizi wezinhlayiyana 0.5 - 3 μm; 

Izinhlayiya ze-Ultrafine: isilinganiso sosayizi wezinhlayiyana

(2) Iziqu zokuhlanganisa

Izinga lokuhlanganisa lezimpushana ngokuvamile libonakala ngomehluko kusayizi wezinhlayiyana phakathi kwezimpushana "zesimo esihlinzekiwe" kanye nezimpushana "zesimo somhlabathi". Izinga lokuhlanganisa le-tungsten powder elicolekileyo livame ukuba phezulu kunalelo lempushana ye-tungsten emahhadla. Ngokukhiqizwa kwezinto ze-tungsten, idigri yokuhlanganisa ithinta ngokuqondile amandla esiqeshana esiluhlaza. Enqubweni yokukhiqiza ye-WC, izinga lokuhlanganisa le-w powder linomthelela ekufaneni kokusatshalaliswa kwekhabhoni. 

(3) I-particle morphology

I-particle morphology ye-tungsten powder inomthelela ekusebenzeni kwayo okucindezelayo namandla omzimba oluhlaza. I-morphology yezinhlayiyana engavamile iholela ekuxhumaneni phakathi kwezinhlayiya, ngaleyo ndlela ithuthukise amandla omzimba oluhlaza. I-tungsten powder eyindilinga inoketshezi oluhle futhi ifaneleka ngokukhethekile ukufutha izinto. Ngokufanayo, lapho ulungiselela i-WC, i-morphology ye-tungsten powder nayo ithinta i-morphology ye-WC powder. 

(4) Indawo Eqondile Yobuso

Ingqikithi yendawo eneyunithi yesisindo se-tungsten powder ibizwa ngokuthi indawo ethile ye-tungsten powder, evame ukuvezwa ngamayunithi we-m2·g-1. Indawo ethize ye-tungsten powder ngokuvamile isukela ku-0.01 kuya ku-12 m2·g-1. Ibonisa ngokungaqondile usayizi wezinhlayiyana kanye ne-morphology ye-tungsten powder futhi iyinkomba ebalulekile yokuhlola umsebenzi we-sintering, izici zokuhlakazeka, kanye nekhono lokusabela ngezinto ezinamagesi neziqinile ngesikhathi senqubo ye-carbonization ye-tungsten powder. 

(5) Ukuminyana okuxekethile kanye nokuminyana okuhlangene

Ukuminyana okuxekethile kanye nokuminyana okuhlangene kwempushana ye-tungsten kuyanda ngokwanda kwesilinganiso sosayizi wezinhlayiyana zempushana. Ubudlelwano phakathi kokuminyana okuxekethile kwempushana ye-tungsten ekhiqizwa ifektri ethile kanye nosayizi wayo omaphakathi wezinhlayiyana ze-Fischers kuboniswe kuThebula 4-4. Ukuncipha kokusatshalaliswa kosayizi wezinhlayiyana zempushana, yilapho i-morphology yezinhlayiya iyinkimbinkimbi, futhi lapho ukuhlanganisa kunamandla, kuba kuncane ukuminyana okuxekethile. Ngokuvamile, amapharamitha enqubo yenqubo yokunciphisa angalungiswa ukuze ayilawule.

(6) Uketshezi

I-fluidity ye-tungsten powder ithonywa usayizi wezinhlayiyana, ukusatshalaliswa kosayizi wezinhlayiyana, kanye ne-particle morphology. Ukuqina kwezinhlayiya zempushana, izinhlayiya eziyindilinga, kanye nokushelela kwendawo, kuba ngcono uketshezi. Uketshezi lwempushana ye-tungsten kuvame ukukalwa ngezinga lokugeleza kweHholo, elivezwa njengesikhathi esithatha u-50g wempushana ye-tungsten ukugeleza embotsheni encane eshiwo kumitha yokugeleza kweHholo. I-fluidity ye-powder ithinta ngokuqondile ukulayishwa kwe-volumetric ngesikhathi senqubo yokucindezela kanye nokufana kwe-die-cast density. 

(7)Ukucindezelwa

I-Compressibility isho ikhono le-tungsten powder elicindezelwa ngaphansi kwezimo ezithile zokucindezela. Kuvame ukukalwa ngesikhunta esijwayelekile ngaphansi kwezimo ezishiwo zokuthambisa, futhi kuvezwa ukuminyana kwempushana komkhiqizo ocindezelwe ngaphansi kwengcindezi ethile. Ingase futhi imelwe igrafu yejika ebonisa ushintsho lokuminyana komkhiqizo ocindezelwe ngokucindezela kokucindezela. 

(8) Ukuhleleka