Pitting ukugqwala: kubangela. ukuvikela izinsimbi ngokumelene ukugqwala Izindlela

Corrosion ngokuthi ukubhujiswa ebusweni izinto asebenzayo ngenxa othola izinqubo redox. Ukubhujiswa izingqimba impahla kuholele ekulahlekelweni amandla, conductivity kagesi, brittleness anda kanye nezinye izakhiwo ze-okusithiyayo metal.

Ngo ukusebenza imikhiqizo metal babhekana nemiphumela elimazayo yemihlobo ehlukeneko nezinhlobo, phakathi okuyinto ivelele pitting. Kuyingozi kakhulu futhi akuqinisekile.

pitting ukugqwala

Uma uyikha phezulu le imikhiqizo metal akuyona into engavamile ukubona ayimigodi encane ngokuya onsundu ngokuphaphathekile noma abe nsundu. Lezi ososayensi abakubiza ngokuthi pitting iphuzu, futhi inqubo ngokubukeka kwabo - pitting. Kwenzeka phezu izinto nabo amanzi olwandle izixazululo nosawoti ahlukahlukene, uketshezi amakhemikhali nolaka futhi eqaphela nezinye izici ezimbi.

Pitting ukugqwala kuthinta kuphela insimbi yekwentiwa kanye Alloys, ukuthuthukisa ikakhulukazi ungqimba ukugqwala noma izindawo izici ezihlukahlukene. "Point izilonda" ingase iphazamise ukusebenza kwe imikhiqizo ehlukahlukene kusukela ulwelwesi mncane futhi chips amayunithi thick-ngodonga. Ngaphezu kwalokho, isimo sazo ukugqwala kusiza kumiswa imifantu is kakhulu ziyancipha inikezwe izici ezibonakalayo.

Isikimu ukwa metal

Ukuze kusebenze pitting kudinga khona reactants ezimbili - activators futhi sequestrants. Njengoba i anions Activator chlorine ngokuvamile isinyathelo, uxhumano lokudlulisa, iodine - ziseZwini ezindaweni eziningi lapho imikhiqizo metal ezisebenza. Basuke adsorbed phezu kwaleyo zensimbi yakha nge izingxenye zalo izakhiwo encibilikayo.

Njengoba passivating amanzi noma iqembu hydroxyl ngokuvamile yenza. Ngokushesha inqubo ekubhujisweni okuphuma ngokuvumelana uhlelo ezilandelayo:

1. Activator ion kuthiwa adsorbed phezu esivikelo (oxide) ifilimu.
2. Kukhona inqubo esikhundleni i-oksijini ion ukuze inqubo athomu Activator.
3. A semali ion encibilikayo, lapho amakhefu ifilimu.

Ngenxa yalokho, ezingaba umehluko kwenzeka kwi yendwangu eholela imisinga wendawo isebenze ngokushesha anodic inqubo. ngaleyo ndlela Activator ion iyiswe izikhungo ukwa, ngenxa okuyinto pitting ukugqwala iqhubeka.

Izinhlobonhlobo pitting ukugqwala

Thayipha pitting ukugqwala kuyahlukahluka kuye ngokuthi izimo zemvelo, ikakhulukazi ku-izinga lokushisa, pH, amakhemikhali ukwakheka kwezinto. Ngaphansi kwethonya lezi zici kuyahlukahluka ifomu imigodi ubukhulu kanye ilungiselelo yabo. Ngakho, ngokuvumelana usayizi ezicezile iphuzu ekubhujisweni:

• ezincane - usayizi ichashaza esingaphansi kuka 0.1 mm;
• ezivamile - ububanzi we imigodi uyahluka 0.1 no 1 mm;
• esidalwa yizilonda emathunjini sibe lapho kumiswa idlule 1 mm ububanzi.

Kuye indawo pitting ukugqwala Kungavulwa noma avaliwe. Esimweni sokuqala, ukuthola iminonjana ekubhujisweni cishe kungenakwenzeka - kubalulekile ukusebenzisa amathuluzi akhethekile. Lolu hlobo lwe-ukugqwala ngokuvamile kuholela ezibangela ukubhalelwa kuziphendulela ngefanelo.

Vula rusting lubonakale ngokubona okubonakala ngeso lenyama. Ngokuvamile pitting ihlangana zibe yomkhakha owodwa. Uma lokhu kwenzeka kungekho nokucekelwa kwezingxenye ukujula futhi ububanzi, ngenxa okuyinto zikhona ezinkulu endaweni zamehlo.

uhlobo imigodi

Ifomu pitting incike imigodi ngaphakathi ngehele crystal okuyinto akhiwa kule izigaba sokuqala sohlelo ukugqwala. Ukwakheka njalo iningi ukuma okungajwayelekile - zivele phezu insimbi engagqwali, carbon futhi ongaphakeme ingxubevange lezinsimbi, aluminium, i-chromium, ne-nickel Alloys, yensimbi.

izilonda Hemispherical yakha ngenxa nokuqedwa isotropic. Le nqubo iyafana electro. Ngokwengxenye lokhu kuchaza phansi shiny of kude lulwimi yindilinga. Lesi sifo siphatha kakhulu ukuba ihlazo, titanium, aluminium, nickel futhi ayibe imikhiqizo enjalo, kanye isakhiwo tantalum. Cishe zohlobo olulodwa has a pitting ka lezinsimbi engagqwali.

Ngaphezu kwalokho, pitting kungenzeka polyhedral futhi faceted. "Izilonda" uhlobo yokugcina zivame kuhlanganiswe nomunye, okuholela ekubhujisweni esikhulu hemispherical.

izimbangela

Ziyini izimbangela eziyinhloko zalokhu okuvela pitting ukugqwala kuphambene ubuchwepheshe ukukhiqizwa futhi isenzo mechanical indaba. Ngenxa yalokho yokuphazamiseka ubuchwepheshe asakazwe metal avele ezihlukahlukene microinclusions ukuthi ukuphazamisa oyiyo. Lokhu kufakwa ezivamile kungenziwa ngokuthi isigayo esikalini.

Ngenxa isenzo awayindwayo ngokuvamile kakhulu phezu kobuso umkhiqizo ucala kutfutfukisa pitting. Izizathu zalokhu amanga ekubhubhiseni elingenhla ifilimu ovikelayo, ukubhidliza isakhiwo sangaphakathi, kusale ebusweni imingcele okusanhlamvu. Inqubo ezivame kakhulu isebenze isici umphumela ashukumisayo, okuholela ukubukeka microcracks.

Pitting ukugqwala of izinsimbi okhula ngokushesha ezindaweni ezinzima, ukuphuma kuwo kanye bedle abezindaba nolaka - amanzi olwandle, izixazululo ene-asidi.

Izindlela lokuzivikela metal kusuka ukugqwala pitting

Ukuvikela imikhiqizo metal ngokumelene pitting izindlela ukusetshenziswa ezintathu eziyinhloko:

1. Ukuqedwa ivaliwe izinhlelo usebenzisa izixazululo compounds ane-alikhali, sulfate, chromates.
2. Isingeniso yezingxenye impahla kanye ukumelana rusting ngephuzu - of molybdenum, i-chromium, i-silicon.
3. Ukusetshenziswa anode futhi cathode ubuchwepheshe ukudala ungqimba zokuzivikela.

Zonke izindlela ukuvikela izinsimbi kusuka ukugqwala isebenza ukukhiqizwa, babedinga amathuluzi zobuchwepheshe kanye capital investment ezinkulu kuphela. Ekuphileni kwethu kwansuku zonke ukushabalalisa ngokuphelele ingozi pitting engenakwenzeka. Kungaba kuphela buthaka ithonya omubi wenza izinto nge-:

• ukusebenzisa ezinengilazi anticorrosive;
• ngcono ukusebenza imikhiqizo enjalo;
• ekunciphiseni izinga asidi, okuyinto ukuxhumana impahla.

Kodwa indlela ephumelela kakhulu futhi iyatholakala iwukuba ngokucophelela ophucuziwe: ekunciphiseni ebusweni maholoholo, wena kanyekanye kwandisa ukugqwala yayo ukumelana. Kodwa imiphumela emihle kakhulu, ukusebenzisa kangcono zonke izindlela ukuvikela izinsimbi ngokumelene ukugqwala ngesikhathi esifanayo.