Pfungwa Huru dzeSimbi yeMuviri
Pendauluan
Kugadzira simbi ibazi rekugadzira simbi rinoongorora hunhu hwezvinhu zvakagadzirwa nesimbi uye shanduko dzinoitika muzvivakwa izvi panguva dzakasiyana siyana. Kunzwisisa izvi kwakakosha muindasitiri nekuti hunhu hwesimbi nesimbi dzine chekuita nekushanda kwadzo uye mashandisirwo adzo muminda yakasiyana-siyana yeinjiniya.
Kugadzira simbi yemuviri kunosanganisira mativi akawanda, anosanganisira kemesitiri, fizikisi, uye makanika ezvinhu. Chinyorwa chino chichaongorora pfungwa huru mukugadzira simbi yemuviri, kusanganisira chimiro chekristaro, madhayagiramu ezvikamu nezvikamu, kukuvara kwekristaro, uye nzira dzekusimbisa simbi.
Chimiro cheKristaro
Simbi dzine chimiro cheatomu chakajairika chinozivikanwa sechimiro chekristaro. Chimiro chekristaro ichi chinogona kutsanangurwa sekurongeka kwemaatomu nguva nenguva munzvimbo ine mativi matatu. Kune simbi zhinji, kune mhando nhatu huru dzezvimiro zvekristaro: simple cubic (BCC), face-centered cubic (FCC), uye hexagonal close-packed (HCP).
1. Maumbirwo eBCC (Muviri-Uri Pakati peCubic): Muumbirwo weBCC, maatomu ari pamakona ecubic pamwe nepakati pecubic. Muenzaniso wesimbi ine maumbirwo eBCC i-alpha iron (α-Fe) patembiricha yemumba.
2. Magadzirirwo eFCC (Face-Centered Cubic): Maatomu ari muchimiro cheFCC ari pakona yega yega yecube uye pakati pechiso chega chega checube. Chimiro ichi chakaoma kupfuura BCC. Mienzaniso yesimbi dzine chimiro cheFCC iaruminiyamu, mhangura, negoridhe.
3. HCP (Hexagonal Close-Packed) Maumbirwo: Muchimiro cheHCP, maatomu ari pamakona uye maatomu maviri ekuwedzera ari mukati meyuniti yesero, zvichigadzira chimiro cheprism chehexagonal. Mienzaniso yesimbi dzine chimiro cheHCP imagnesium netitanium.
Dhayagiramu yeDanho neDanho
Chikamu (phase) inzvimbo iri muchinhu umo maumbirwo acho nechimiro chayo zvakafanana. Dhayagiramu yechidanho chishandiso chinoshandiswa kunzwisisa nekufanotaura chimiro chechikamu chechinhu pakupisa nekumanikidzwa kwakasiyana-siyana.
1. Dhizaini yeChikamu Chimwe Chete: Inoratidza hukama huripo pakati pekupisa nekumanikidzwa kwemhando imwe chete yezvinhu. Semuenzaniso, dhayagiramu yechikamu chemvura inoratidza kupatsanurwa pakati pezvikamu zvemvura, zvakasimba, uye gasi.
2. Dhiagiramu yeBinary: Inoratidza hukama huripo pakati pekupisa nekuumbwa kwemusanganiswa wemhando mbiri dzezvinhu. Dhiagiramu yeBinary inowanzo shandiswa mukugadzira simbi kunzwisisa alloys dzesimbi dzakadai sesimbi-kabhoni (Fe-C), idzo dzinokosha pasimbi.
3. Kuchinja kwechikamu: Maitiro ekuchinja kwechinhu kubva pane chimwe chikamu kuenda kune chimwe, senge kubva pane chakaoma kuenda kune chemvura (kunyunguduka) kana kubva pane chakaoma kuenda kune chakasimba (kushanduka kweallotropic). Muenzaniso wekare wekuchinja kwechikamu musimbi ndiko kuchinja kubva ku austenite kuenda ku martensite musimbi yekabhoni, iyo inokosha pakuomesa simbi.
Kukuvadzwa kweKristaro
Zvikanganiso zvemakristaro kusakwana kuri muchimiro chekristaro kunogona kukanganisa hunhu hwesimbi uye hwemuchina. Zvikanganiso izvi zvinowanzo kamurwa kuita zvikamu zvitatu zvikuru: zvikanganiso zvemapoinzi, zvikanganiso zvemutsetse (dislocations), uye zvikanganiso zveplane.
1. Kukuvadzwa kwePoint: Kunosanganisira ma "interstitials" (maatomu ekune dzimwe nyika akaiswa mu "crystal lattice") uye "vacancies" (kuvapo kwema "points" asina maatomu). Kukuvadzwa kwePoint kunowanzo kukanganisa kupararira uye kushanduka kwe "phase" musimbi.
2. Kubviswa kweMutsetse: Uku kukanganisa kunokonzera kukanganiswa kwechimiro chekristaro. Kune mhando mbiri huru dzekubviswa kwemupendero: kubviswa kwemucheto uye kubviswa kwescrew. Kubviswa uku kunoita basa rakakosha mukuita kwekuchinja kwepurasitiki uye maitiro ekuomesa basa.
3. Kukuvara kwePlanar: Kunosanganisira miganhu yezviyo nemiganhu yezvikamu. Muganhu wezviyo inzvimbo inosangana zvidimbu zviviri zvekristaro zvine maonero akasiyana. Miganhu iyi inogona kukanganisa hunhu hwemakanika, senge simba uye kusimba.
Nzira yekusimbisa Simbi
Nzira dzekusimbisa simbi dzinovavarira kuwedzera simba rechinhu kuburikidza nenzira dzakasiyana-siyana. Dzimwe nzira dzekusimbisa dzakajairika dzinosanganisira:
1. Kuomesa Mhinduro Yakasimba: Kusimba uku kunoitika kana maatomu esimbi achinyungudika musimbi, zvichikonzera kukanganiswa mu crystal lattice uye zvichidzivisa kufamba kwe dislocations. Muenzaniso i alloy yemhangura ne zinc mu brass.
2. Kuomesa simbi: Kunozivikanwawo sekusimbisa simbi, kunoitika kana simbi yave plastically deformed, zvichiita kuti disaslocations dzipararire. Kuomesa uku kunowedzera simba nekuoma kwesimbi asi kunoderedza ductility.
3. Kuomesa Zvidimbu: Kunosanganisira kuumbwa kwezvidimbu musimbi zvinodzivisa kufamba kwezvidimbu. Muenzaniso ndewokuoma kuburikidza nezvinotsvedza muaruminiyamu alloys.
4. Kudzora Muganhu weZviyo: Simba rinowedzera nekuderedza saizi yezviyo. Miganhu yeZviyo inoshanda sezvipingamupinyi pakufamba kwezviyo. Dzidziso yeHall-Petch inoti simba resimbi rinowedzera nekudzikira kwehukuru hwezviyo.
Mashandisirwo uye Zvazvinoreva
Kunzwisisa zvakadzama pfungwa huru dzesimbi dzemuviri kwakakosha mumabasa akasiyana-siyana emaindasitiri, akadai se:
1. Indasitiri yeMotokari: Kushandiswa kwesimbi ine hunhu hwemakanika hwakagadziriswa kuburikidza nekupisa uye makemikari ekugadzirisa mafuremu emota.
2. Indasitiri yeNdege: Kushandisa aruminiyamu netitanium alloys dzakareruka asi dzakasimba pakugadzira zvinhu zvendege.
3. Kugadzira Simbi: Maitiro ekubvisa nekunatsa simbi kubva mumatombo adzo kuenda kuzvinhu zvekupedzisira zvakaita sesimbi, waya, nemapaipi.
4. Simba: Kushandiswa kwesimbi dzakakosha dzezvinhu zviri mumagasi nematurbine enyukireya zvinofanira kutsungirira kupisa kwakanyanya uye mamiriro ekumanikidzwa.
Mhedziso
Kugadzira simbi mumuviri ibazi resainzi rakapfuma uye rakaoma kunzwisisa rinoongorora hunhu hwesimbi. Pfungwa huru dzakadai sechimiro chekristaro, madhayagiramu echikamu, zvikanganiso zvekristaro, uye nzira dzekusimbisa zvinhu ndizvo zvakakosha pakunzwisisa maitiro esimbi uye kuti dzinogona kushandiswa sei kuti dzigutse zvinodiwa chaizvo. Ruzivo mukugadzira simbi mumuviri harungobatsiri chete mukugadzirwa kwezvinhu zvitsva asiwo runovandudza kushanda zvakanaka uye kugara kwenguva refu kwezvigadzirwa zviripo, zvichigadzira nzira yekuenderera mberi nekuvandudzwa kwemaindasitiri.
