Maikorosikopu yemaelektroni yakaongororwa kuti ione kutyoka kwekuneta uye kuongorora mashandiro ekutyoka; panguva imwe chete, bvunzo yekuneta yekutenderera kwespin bending yakaitwa pazviyero zvakabviswa kabhoni patembiricha dzakasiyana kuti ienzanise hupenyu hwekuneta kwesimbi yekuyedza ine uye isina kubviswa kabhoni, uye kuongorora mhedzisiro yekubviswa kabhoni pakushanda kwekuneta kwesimbi yekuyedza. Mhedzisiro yacho inoratidza kuti, nekuda kwekuvapo panguva imwe chete kwe oxidation uye kubviswa kabhoni mukudziyisa, kusangana pakati pezviviri, zvichikonzera ukobvu hwechikamu chakabviswa kabhoni nekukura kwetembiricha kunoratidza maitiro ekuwedzera uye kuderera, ukobvu hwechikamu chakabviswa kabhoni hunosvika kukosha kwakanyanya kwe120 μm pa750 ℃, uye ukobvu hwechikamu chakabviswa kabhoni hunosvika kukosha kushoma kwe20 μm pa850 ℃, uye muganho wekuneta kwesimbi yekuyedza ungangoita 760 MPa, uye sosi yekutsemuka kwekuneta musimbi yekuyedza inonyanya kuve Al2O3 non-metallic inclusions; Maitiro ekubvisa kabhoni anoderedza zvakanyanya hupenyu hwekuneta kwesimbi yekuyedza, zvichikanganisa mashandiro ekuneta kwesimbi yekuyedza, ukobvu hwechikamu chekubvisa kabhoni, uye hupenyu hwekuneta hunoderedza. Kuti kuderedze kukanganiswa kwechikamu chekubvisa kabhoni pakushanda kwekuneta kwesimbi yekuyedza, tembiricha yakakwana yekurapa kupisa kwesimbi yekuyedza inofanira kuiswa pa850℃.
Giya chinhu chakakosha chemotokari,Nekuda kwekushanda nekukurumidza, chikamu chemeshi chegiya chinofanira kunge chine simba rakawanda uye chinodzivirira kukwesha, uye mudzi wezino unofanirwa kunge uine kugona kwakanaka kwekukotama nekuda kwekuremerwa nguva dzose, kuitira kudzivirira kutsemuka kunotungamira pakutyoka kwezvinhu. Tsvagiridzo inoratidza kuti kubviswa kwekabhoni chinhu chakakosha chinokanganisa mashandiro ekuneta kwesimbi, uye kushanda kwekuneta kwekabhoni chiratidzo chakakosha chemhando yechigadzirwa, saka zvakakosha kudzidza maitiro ekubvisa kabhoni uye mashandiro ekuneta kwekabhoni echinhu chekuyedza.
Mupepa rino, choto chekupisa chiri pa20CrMnTi gear steel surface decarburization test, chinoongorora tembiricha dzakasiyana dzekupisa padanho rekuyedza re decarburization layer remutemo unochinja; uchishandisa muchina weQBWP-6000J uri nyore wekuyedza kuneta we beam pakuedza kwe steel rotary bending fatigue test, kuona mashandiro e test steel fatigue, uye panguva imwe chete kuongorora kukanganiswa kwe decarburization pakushanda kwekuneta kwe test steel pakugadzirwa chaiko kuti uvandudze maitiro ekugadzira, kusimudzira mhando yezvigadzirwa uye kupa referensi inonzwisisika. Kushanda kwe test steel fatigue kunosarudzwa nemuchina we test fatigue we spin bending.
1. Zvishandiso zvekuedza uye nzira dzekuedza
Zvinhu zvekuyedza zveyuniti inopa simbi yegiya ye20CrMnTi, iyo inonyanya kuumbwa nemakemikari sezvakaratidzwa muTafura 1. Kuyedza kwekubvisa kabhururi: zvinhu zvekuyedza zvinogadziriswa kuita sampuli yeF8 mm × 12 mm, pamusoro payo panofanira kunge pakajeka pasina mavara. Chitofu chekupisa chakapiswa kusvika 675 ℃, 700 ℃, 725 ℃, 750 ℃, 800 ℃, 850 ℃, 900 ℃, 950 ℃, 1,000 ℃, mumuenzaniso uye zvinochengetwa kweawa imwe, uye zvobva zvatonhodzwa nemhepo kusvika patembiricha yemukamuri. Mushure mekurapa kupisa kwemuenzaniso nekuisa, kukuya nekupukuta, ne4% yemvura yakabviswa ne nitric acid alcohol solution, kushandiswa kwe microscopy ye metallurgical kuona simbi yekuyedza kubvisa kabhururi, kuyera kudzika kwe decarburization layer patembiricha dzakasiyana. Kuyedzwa kwekuneta kwekutenderera: chinhu chekuyedza zvinoenderana nezvinodiwa pakugadzirisa mapoka maviri emhando dzekuneta dzekutenderera, boka rekutanga hariite bvunzo yekubvisa kabhoni, boka rechipiri rekuongorora kubvisa kabhoni pakupisa kwakasiyana. Uchishandisa muchina wekuyedza kwekuneta wekutenderera, mapoka maviri esimbi yekuyedza yekutenderera kwekuneta, kuona muganho wekuneta wemapoka maviri esimbi yekuyedza, kuenzanisa hupenyu hwekuneta hwemapoka maviri esimbi yekuyedza, kushandisa scanning electron microscope fatigue fracture observation, kuongorora zvikonzero zvekuputsika kwemuenzaniso, kuongorora mhedzisiro yekubvisa kabhoni pahunhu hwekuneta kwesimbi yekuyedza.
Tafura 1 Kuumbwa kwemakemikari (chikamu chehuremu) chesimbi yekuyedza wt%
Mhedzisiro yekupisa tembiricha pakubvisa kabhoni mumafuta
Maumbirwo ehurongwa hwekubvisa kabhoni pasi pekupisa kwakasiyana anoratidzwa muMufananidzo 1. Sezvatinoona kubva pamufananidzo, kana tembiricha iri 675 ℃, pamusoro pemuenzaniso hapaonekwe se decarburization layer; kana tembiricha yakwira kusvika 700 ℃, sample surface decarburization layer yakatanga kuoneka, kune ferrite decarburization layer yakatetepa; netembiricha yakwira kusvika 725 ℃, sample surface decarburization layer thin thin thin; ne tembiricha yakwira kusvika 725 ℃, sample surface decarburization layer thick ... Kana tembiricha ikaramba ichikwira kusvika 850 ℃ zvichikwira, ukobvu hwesimbi yekuyedza yakazara decarburization layer hunoramba huchidzikira, ukobvu hwehafu decarburization layer hwakatanga kuwedzera zvishoma nezvishoma kusvika morphology yakazara decarburization layer yanyangarika, hafu decarburization layer morphology yapera zvishoma nezvishoma. Zvinogona kuonekwa kuti ukobvu hwe full decarburized layer nekuwedzera kwekupisa hwakatanga kuwedzerwa uye hwakaderedzwa, chikonzero chechiitiko ichi imhaka yemuenzaniso mukudziisa panguva imwe chete maitiro e oxidation ne decarburization, chete kana chiyero che decarburization chikamhanya kupfuura kumhanya kwe oxidation chichaonekwa decarburization phenomenon. Pakutanga kwekudziisa, ukobvu hwe full decarburized layer hunowedzera zvishoma nezvishoma nekuwedzera kwekupisa kusvika core decarburized layer yasvika pakakwirira, panguva ino kuti irambe ichikwidza tembiricha, specimen oxidation rate inokurumidza kupfuura decarburization rate, iyo inodzivisa kuwedzera kwe full decarburized layer, zvichikonzera kudzikira. Zvinogona kuonekwa kuti, mukati mehukuru hwe675 ～950 ℃, ukobvu hwechikamu chakabviswa kabhoni pa750 ℃ ndihwo hwakakura, uye ukobvu hwechikamu chakabviswa kabhoni pa850 ℃ ndihwo hudiki, saka, tembiricha yekupisa yesimbi yekuyedza inokurudzirwa kuva 850 ℃.
Mufananidzo 1: Histomorphology yesimbi yekuyedza yakabviswa kabhoni inobatwa pakupisa kwakasiyana kweawa imwe chete
Zvichienzaniswa nechikamu chakabviswa kabhoni, ukobvu hwechikamu chakabviswa kabhoni zvachose hune mhedzisiro yakaipa zvakanyanya pahunhu hwezvinhu, zvinoderedza zvakanyanya hunhu hwemuchina hwechinhu, zvakaita sekuderedza simba, kuomarara, kuramba kupfeka uye muganho wekuneta, nezvimwewo, uye zvakare kuwedzera kunzwa kwekutsemuka, zvichikanganisa mhando yewelding nezvimwewo. Saka, kudzora ukobvu hwechikamu chakabviswa kabhoni chose kwakakosha zvikuru kuvandudza mashandiro echigadzirwa. Mufananidzo 2 unoratidza curve yekuchinja kweukobvu hwechikamu chakabviswa kabhoni chose netembiricha, izvo zvinoratidza kusiyana kweukobvu hwechikamu chakabviswa kabhoni zvakajeka. Zvinogona kuonekwa kubva pamufananidzo kuti ukobvu hwechikamu chakabviswa kabhoni chose hungori 34μm chete pa700℃; netembiricha ichikwira kusvika pa725 ℃, ukobvu hwechikamu chakabviswa kabhoni chose hunowedzera zvakanyanya kusvika 86 μm, inova kanopfuura kaviri ukobvu hwechikamu chakabviswa kabhoni chose pa700 ℃; Kana tembiricha yakwidzwa kusvika pa750 ℃, ukobvu hwechikamu chakabviswa kabhoni zvachose Kana tembiricha yakwira kusvika pa750 ℃, ukobvu hwechikamu chakabviswa kabhoni zvachose hunosvika pa120 μm; sezvo tembiricha ichiramba ichikwira, ukobvu hwechikamu chakabviswa kabhoni zvachose hunotanga kudzikira zvakanyanya, kusvika pa70 μm pa800℃, uye wozosvika pamutengo wakaderera weinenge 20μm pa850℃.
Mufananidzo 2. Ukobvu hwechikamu chakabviswa kabhoni zvachose pakupisa kwakasiyana
Mhedzisiro yekubvisa kabhoni mukushanda kwekuneta mukukotama kwe spin
Kuti tidzidze nezvemhedzisiro yekubvisa kabhoni pahunhu hwekuneta kwesimbi yechitubu, mapoka maviri ekuyedzwa kwekuneta kwe spin bending akaitwa, boka rekutanga rakaongororwa kuneta zvakananga pasina kubvisa kabhoni, uye boka rechipiri rakaongororwa kuneta mushure mekubvisa kabhoni padanho rimwe chete rekushushikana (810 MPa), uye maitiro ekubvisa kabhoni akaitwa pa700-850 ℃ kweawa imwe chete. Boka rekutanga rezviyero rinoratidzwa muTafura 2, inova hupenyu hwekuneta kwesimbi yechitubu.
Hupenyu hwekuneta kweboka rekutanga rezviyero hunoratidzwa muTafura 2. Sezvatinoona kubva muTafura 2, pasina kubviswa kwecarburization, simbi yekuyedza yakangoitwa 107 cycles pa810 MPa, uye hapana kutyoka kwakaitika; apo stress level yakadarika 830 MPa, mimwe yemimwe sampuli yakatanga kutyoka; apo stress level yakadarika 850 MPa, mimwe stress sampuli yakatyoka yese.
Tafura 2 Hupenyu hwekuneta pasi pemazinga akasiyana ekushushikana (pasina kubviswa kwemakabhoni)
Kuti uone muganho wekuneta, nzira yeboka inoshandiswa kuona muganho wekuneta wesimbi yekuyedza, uye mushure mekuongorora data, muganho wekuneta wesimbi yekuyedza unenge 760 MPa; kuti uratidze hupenyu hwekuneta hwesimbi yekuyedza pasi pekumanikidzwa kwakasiyana, SN curve inorongedzwa, sezvakaratidzwa muMufananidzo 3. Sezvatinoona kubva kuMufananidzo 3, mazinga akasiyana ekushushikana anoenderana nehupenyu hwakasiyana hwekuneta, apo hupenyu hwekuneta hwe7, hunoenderana nehuwandu hwema cycles e107, zvinoreva kuti sampuli pasi pemamiriro aya iri kuburikidza nemamiriro ezvinhu, kukosha kwekushushikana kunoenderana kunogona kufungidzirwa sehuwandu hwesimba rekuneta, kureva, 760 MPa. Zvinogona kuonekwa kuti S-N curve yakakosha pakuona hupenyu hwekuneta hwezvinhu zvine kukosha kwakakosha.
Mufananidzo 3 SN curve yekuedza kwesimbi inotenderera inokotama kuedzwa kwekuneta
Hupenyu hwekuneta hweboka rechipiri rezviyero hunoratidzwa muTafura 3. Sezvatinoona kubva paTafura 3, mushure mekunge simbi yekuyedza yabviswa kabhoni pakupisa kwakasiyana, huwandu hwema cycles hunodzikira zviri pachena, uye hunopfuura 107, uye zviyero zvese zvekuneta zvinotyoka, uye hupenyu hwekuneta hunodzikira zvikuru. Pamwe chete nehukobvu hwe layer hwakabviswa kabhoni hwataurwa pamusoro apa ne curve yekuchinja kwekushisa kunogona kuonekwa, ukobvu hwe layer hwakabviswa kabhoni hwa750 ℃ hwakakura kwazvo, hunoenderana nehukuru hwakaderera hwehupenyu hwekuneta. 850 ℃ husina kabhoni hwakabviswa kabhoni hudiki, hunoenderana nehupenyu hwekuneta hwakakwirira. Zvinogona kuonekwa kuti maitiro ekubvisa kabhoni anoderedza zvakanyanya kushanda kwekuneta kwezvinhu, uye kana layer yakabviswa kabhoni yakakora, hupenyu hwekuneta hunowedzera kudzikira.
Tafura 3. Hurefu hwekuneta pakupisa kwakasiyana-siyana kwekubvisa kabhoni (560 MPa)
Kuumbwa kwebvudzi rekuneta kwemuenzaniso kwakaonekwa nekutarisa maikorosikopu emagetsi, sezvakaratidzwa muMufananidzo 4. Mufananidzo 4(a) wenzvimbo inobva bvudzi, mufananidzo unogona kuonekwa pachena, zvichienderana nebvudzi rekuneta kuti uwane kwakabva kuneta, unogona kuonekwa, kwakabva bvudzi re "fish-eye" non-metallic inclusions, inclusions pahuwandu hwekushushikana huri nyore kukonzera, zvichikonzera bvudzi rekuneta; Mufananidzo 4(b) wechimiro chenzvimbo inowedzera bvudzi, unogona kuonekwa pachena mitsetse yekuneta, waive wakafanana nerwizi, ndewekutyoka kwe quasi-dissociative, nekutyoka kwe quasi-dissociative, nekutyoka kwe bvudzi kuchikura, pakupedzisira kuchikonzera kutyoka. Mufananidzo 4(b) unoratidza chimiro chenzvimbo inowedzera bvudzi, mitsetse yekuneta yakajeka inogona kuonekwa, muchimiro chekugoverwa kwakafanana nerwizi, kwaive kwekutyoka kwe quasi-dissociative, uye nekuenderera mberi kwekuputika kwe bvudzi, pakupedzisira zvichikonzera kutyoka.
Kuongorora kuneta nekutsemuka kwemakumbo
Mufananidzo 4. Maumbirwo eSEM epamusoro pesimbi yekuyedza ine kuneta
Kuti tizive mhando yezvinosanganisirwa muMufananidzo 4, ongororo yekugadzirwa kwesimba remagetsi yakaitwa, uye mhedzisiro yacho inoratidzwa muMufananidzo 5. Zvinogona kuonekwa kuti zvinosanganisirwa zvisiri zvesimbi zvinonyanya kuve Al2O3 inclusions, zvichiratidza kuti zvinosanganisirwa ndizvo zvinonyanya kukonzera kutsemuka kunokonzerwa nekutsemuka kwezvinosanganisirwa.
Mufananidzo 5 Energy Spectroscopy yeZvinhu Zvisiri zveMetallic Inclusions
Mhedziso
(1) Kuisa tembiricha yekudziyisa pa850 ℃ kunoderedza ukobvu hwechikamu chakabviswa kabhoni kuderedza mhedzisiro pakushanda kwekuneta.
(2) Muganho wekuneta kwekukombama kwesimbi yekuyedza i760 MPa.
(3) Kutsemuka kwesimbi muzvinhu zvisiri zvesimbi, kunyanya musanganiswa weAl2O3.
(4) kubvisa kabhoni mu simbi yekuyedza kunoderedza zvakanyanya nguva yekuneta kwesimbi yekuyedza, ukobvu hwe decarburization layer, uye nguva yekuneta yakaderera.
Nguva yekutumira: Chikumi-21-2024
