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Izilayidi ezibonisa izindatshana ezintathu zesilayidi ngasinye.Sebenzisa izinkinobho ezingemuva nezilandelayo ukuhamba phakathi kwamaslayidi, noma izinkinobho zokulawula ama-slide ekugcineni ukuze uhambe kuslayidi ngasinye.
Insimbi engagqwali 310 amashubhu ahlanganisiwe / amashubhu ahlanganisiweUkwakheka Kwamakhemikhalikanye nokwakheka
Ithebula elilandelayo libonisa ukwakheka kwamakhemikhali ebangeni lama-310S ensimbi engagqwali.
10*1mm 9.25*1.24 mm 310 abahlinzeki beshubhu yensimbi engagqwali ehlanganisiwe
| Isici | Okuqukethwe (%) |
| Iron, Fe | 54 |
| I-Chromium, uCr | 24-26 |
| Nickel, Ni | 19-22 |
| IManganese, Mn | 2 |
| Silicon, Si | 1.50 |
| Carbon, C | 0.080 |
| I-Phosphorous, P | 0.045 |
| Isibabule, S | 0.030 |
Izakhiwo Zomzimba
Izakhiwo ezibonakalayo zebanga lama-310S zensimbi engagqwali ziboniswa etafuleni elilandelayo.
| Izakhiwo | Imethrikhi | I-Imperial |
| Ukuminyana | 8g/cm3 | 0.289 lb/in³ |
| Iphoyinti lokuncibilika | 1455°C | 2650°F |
Izakhiwo Zemishini
Ithebula elilandelayo libonisa izici zemishini yezinga lama-310S lensimbi engagqwali.
| Izakhiwo | Imethrikhi | I-Imperial |
| Amandla aqinile | 515 MPa | Idatha ye-74695 |
| Amandla esivuno | 205 MPa | 29733 psi |
| I-Elastic module | 190-210 GPA | 27557-30458 ksi |
| Isilinganiso sikaPoisson | 0.27-0.30 | 0.27-0.30 |
| Ukwelula | 40% | 40% |
| Ukuncishiswa kwendawo | 50% | 50% |
| Ukuqina | 95 | 95 |
Izakhiwo ezishisayo
Izakhiwo ezishisayo ze-grade 310S zensimbi engagqwali zinikezwe etafuleni elilandelayo.
| Izakhiwo | Imethrikhi | I-Imperial |
| I-Thermal conductivity (ye-stainless 310) | 14.2 W/mK | 98.5 BTU in/ihora ft².°F |
Amanye Amagama
Ezinye izincazelo ezilingana nebanga 310S lensimbi engagqwali zibalwe kuthebula elilandelayo.
| I-AMS 5521 | I-ASTM A240 | I-ASTM A479 | I-DIN 1.4845 |
| I-AMS 5572 | I-ASTM A249 | I-ASTM A511 | QQ S763 |
| I-AMS 5577 | I-ASTM A276 | I-ASTM A554 | I-ASME SA240 |
| I-AMS 5651 | I-ASTM A312 | I-ASTM A580 | I-ASME SA479 |
| I-ASTM A167 | I-ASTM A314 | I-ASTM A813 | I-SAE 30310S |
| I-ASTM A213 | I-ASTM A473 | I-ASTM A814 |
Inhloso yalolu cwaningo ukuhlola impilo yokukhathala yesiphethu se-valve yenjini yemoto lapho kusetshenziswa ama-microdefect ocingweni oluqine uwoyela oluwu-2300 MPa grade (i-OT wire) enokukhubazeka okujulile okungu-2.5 mm ububanzi.Okokuqala, ukuguqulwa kokukhubazeka okungaphezulu kocingo lwe-OT ngesikhathi kwakhiwa isiphethu se-valve kutholwe ngokuhlaziywa kwesici esilinganiselwe kusetshenziswa izindlela zokufanisa, futhi ukucindezeleka okusalayo kwentwasahlobo eqediwe kukalwa futhi kwasetshenziswa kumodeli yokuhlaziya ukucindezeleka kwasentwasahlobo.Okwesibili, hlaziya amandla entwasahlobo ye-valve, hlola ukucindezeleka okusalayo, futhi uqhathanise izinga lokucindezeleka okusetshenzisiwe nokungapheleli kwendawo.Okwesithathu, umphumela wama-microdefects empilweni yokukhathala yasentwasahlobo wahlolwa ngokusebenzisa ingcindezi kumaphutha angaphezulu atholwe ekuhlaziyweni kwamandla asentwasahlobo kuya kumajika e-SN atholwe ekuhlolweni kokukhathala okuguquguqukayo ngesikhathi sokuzungezisa intambo ye-OT.Ukushona kwesici okungu-40 µm kuyindinganiso yamanje yokulawula ukonakala ngaphandle kokufaka engozini impilo yokukhathala.
Imboni yezimoto inesidingo esinamandla sezingxenye zezimoto ezingasindi ukuze kuthuthukiswe ukusebenza kahle kukaphethiloli ezimotweni.Ngakho-ke, ukusetshenziswa kwensimbi enamandla aphezulu (AHSS) kuye kwanda eminyakeni yamuva.Imithombo yamavalvu enjini yezimoto ikakhulukazi ihlanganisa izintambo zensimbi ezingagugi, ezingagugi nezingagegi (izintambo ze-OT).
Ngenxa yamandla azo aqinile (1900–2100 MPa), izintambo ze-OT ezisetshenziswa njengamanje zenza kube nokwenzeka ukunciphisa ubukhulu nesisindo seziphethu zamavalvu enjini, kuthuthukiswe ukusebenza kahle kukaphethiloli ngokunciphisa ukungqubuzana nezingxenye ezizungezile1.Ngenxa yalezi zinzuzo, ukusetshenziswa kwentambo yocingo olunamandla amakhulu kukhula ngokushesha, futhi induku yocingo enamandla kakhulu yeklasi engu-2300MPa ivela ngokulandelana.Iziphethu zamavalvu ezinjinini zezimoto zidinga impilo ende yesevisi ngoba zisebenza ngaphansi kwemithwalo ephezulu yama-cyclic.Ukuze kuhlangatshezwane nalesi sidingo, abakhiqizi ngokuvamile bacabangela impilo yokukhathala engaphezu kwemijikelezo engu-5.5×107 lapho beklama iziphethu ze-valve futhi basebenzise ingcindezi eyinsalela endaweni yesiphethu se-valve ngokuvula isibhamu kanye nezinqubo zokunciphisa ukushisa ukuze kuthuthukiswe impilo yokukhathala2.
Kube khona izifundo ezimbalwa mayelana nempilo yokukhathala kweziphethu ze-helical ezimotweni ngaphansi kwezimo ezijwayelekile zokusebenza.Gzal et al.I-Analytical, experimental and finite element (FE) ihlaziya iziphethu ze-elliptical helical ezinama-engeli amancane we-helix ngaphansi komthwalo omile ziyethulwa.Lolu cwaningo lunikeza inkulumo ecacile nelula yendawo yokucindezela okukhulu kwe-shear kuqhathaniswa ne-aspect ratio kanye nenkomba yokuqina, futhi inikeza ukuqonda kokuhlaziya ekucindezelweni okuphezulu kwe-shear, ipharamitha ebalulekile kumiklamo esebenzayo3.Pastorcic et al.Imiphumela yokuhlaziywa kokubhujiswa nokukhathala kwesiphethu se-helical esikhishwe emotweni yangasese ngemuva kokwehluleka ekusebenzeni kuchazwe.Kusetshenziswa izindlela zokuhlola, isiphethu esiphukile sahlolwa futhi imiphumela iphakamisa ukuthi lesi yisibonelo sokungaphumeleli kokugqwala4.imbobo, njll. Amamodeli amaningi empilo yasentwasahlobo yokuhlehla komugqa athuthukisiwe ukuze ahlole impilo yokukhathala yama-helical springs ezimoto.Putra nabanye.Ngenxa yokungalingani kwendawo yomgwaqo, impilo yesevisi ye-helical spring yemoto inqunywa.Kodwa-ke, luncane ucwaningo olwenziwe mayelana nokuthi ukukhubazeka okungaphezulu okwenzeka ngesikhathi sokukhiqiza kuthinta kanjani impilo yemithombo yamakhoyili ezimotweni.
Ukukhubazeka okungaphezulu okwenzeka ngesikhathi senqubo yokukhiqiza kungaholela ekugxilweni kwengcindezi yendawo emithonjeni yama-valve, okunciphisa kakhulu impilo yabo yokukhathala.Ukukhubazeka okungaphezulu kwemithombo yama-valve kubangelwa izici ezihlukahlukene, njengokonakala kwendawo yezinto ezingavuthiwe ezisetshenziswayo, ukukhubazeka kumathuluzi, ukuphatha kabi ngesikhathi sokugoqeka okubandayo7.Amaphutha angaphezulu kwempahla eluhlaza amise okwe-V ngenxa yokugoqa okushisayo kanye nomdwebo onamaphasi amaningi, kuyilapho amaphutha abangelwa ithuluzi lokwakha nokuphatha ngokunganaki kumise okwe-U enemithambeka ethambile8,9,10,11.Ukukhubazeka okumise okuka-V kubangela ukugxila okuphezulu kwengcindezi kunokushiyeka okumise okuka-U, ngakho-ke imibandela yokulawula okuqinile ivamise ukusetshenziswa endabeni yokuqala.
Amazinga amanje okuphatha ukonakala kwendawo yezintambo ze-OT ahlanganisa i-ASTM A877/A877M-10, i-DIN EN 10270-2, i-JIS G 3561, ne-KS D 3580. I-DIN EN 10270-2 icacisa ukuthi ukujula kwesici esingaphezulu kumadayimitha ezintambo angu-0.5– I-10 mm ingaphansi kuka-0.5-1% wobubanzi bocingo.Ukwengeza, i-JIS G 3561 kanye ne-KS D 3580 zidinga ukuthi ukujula kokulimala okungaphezulu endongeni yocingo enobubanzi obungu-0.5-8 mm kube ngaphansi kuka-0.5% wobubanzi bocingo.Ku-ASTM A877/A877M-10, umenzi nomthengi kufanele bavumelane ngokujula okuvunyelwe kokulimala kwendawo.Ukulinganisa ukujula kwesici ebusweni bocingo, ucingo luvame ukufakwa nge-hydrochloric acid, bese ukujula kwesici kulinganiswa kusetshenziswa i-micrometer.Kodwa-ke, le ndlela ingakala kuphela amaphutha ezindaweni ezithile hhayi kuwo wonke umkhiqizo wokugcina.Ngakho-ke, abakhiqizi basebenzisa ukuhlolwa kwamanje kwe-eddy ngesikhathi senqubo yokudweba ucingo ukuze balinganise ukukhubazeka kwendawo ocingweni olukhiqizwa ngokuqhubekayo;lezi zivivinyo zingakala ukujula kokonakala kwendawo kuze kufike ku-40 µm.Intambo yensimbi yezinga elingu-2300MPa engaphansi kokuthuthukiswa inamandla aqinile aqinile kanye nobude obuphansi kunocingo lwensimbi olukhona lwebanga le-1900-2200MPa, ngakho-ke impilo yokukhathala kwe-valve yasentwasahlobo ithathwa njengokuzwela kakhulu kumaphutha angaphezulu.Ngakho-ke, kuyadingeka ukuhlola ukuphepha kokusebenzisa izindinganiso ezikhona zokulawula ukujula kokukhubazeka kwendawo yensimbi yensimbi grade 1900-2200 MPa kuya ku-steel wire grade 2300 MPa.
Inhloso yalolu cwaningo ukuhlola impilo yokukhathala yesiphethu sevalvu yenjini yezimoto lapho ubuncane bokujula kwephutha obulinganiswa ngokuhlolwa kwamanje kwe-eddy (okungukuthi 40 µm) kusetshenziswa ocingweni lwe-OT lwebanga elingu-2300 MPa (ububanzi: 2.5 mm): iphutha elibalulekile ukujula .Igalelo nendlela yalolu cwaningo imi kanje.
Njengokushiyeka kokuqala ocingweni lwe-OT, kusetshenziswe isici esimise okuka-V, esithinta kakhulu impilo yokukhathala, ekuqondeni okuphambene okuhlobene ne-axis yocingo.Cabangela isilinganiso sobukhulu (α) nobude (β) besici esingaphezulu ukuze ubone umthelela wokujula (h), ububanzi (w), nobude (l).Ukulimala okungaphezulu kwenzeka ngaphakathi kwentwasahlobo, lapho ukwehluleka kwenzeka kuqala.
Ukubikezela ukuguqulwa kweziphambeko zokuqala ocingweni lwe-OT ngesikhathi sokuvunguza okubandayo, kwasetshenziswa indlela yokulingisa encane, ecabangela isikhathi sokuhlaziya kanye nobukhulu bezinkinga ezingaphezulu, njengoba ukukhubazeka kuncane kakhulu uma kuqhathaniswa nocingo lwe-OT.imodeli yomhlaba wonke.
Ukucindezelwa kwensalela kokucindezela entwasahlobo ngemva kokuchama kwesiteji ezimbili kubalwe ngendlela yesici esilinganiselwe, imiphumela yaqhathaniswa nezilinganiso ngemva kokuchama kwesibhamu ukuze kuqinisekiswe imodeli yokuhlaziya.Ngaphezu kwalokho, ukucindezeleka okuyinsalela emithonjeni yama-valve kuzo zonke izinqubo zokukhiqiza kwalinganiswa futhi kwasetshenziswa ekuhlaziyeni amandla entwasahlobo.
Ukucindezeleka kokukhubazeka okungaphezulu kubikezelwa ngokuhlaziya amandla entwasahlobo, kucatshangelwa ukuguqulwa kwesici ngesikhathi sokugoqa okubandayo kanye nokucindezeleka okusalayo kokucindezela entwasahlobo ephelile.
Ukuhlolwa kokukhathala okugobayo okujikelezayo kwenziwa kusetshenziswa intambo ye-OT eyenziwe ngento efanayo ne-valve spring.Ukuze kuhlotshaniswe ingcindezi eyinsalela kanye nezici zokuqina kobuso beziphethu ze-valve ezakhiwe emigqeni ye-OT, amajika e-SN atholwe ngokuzungezisa ukuhlolwa kokukhathala okugobayo ngemva kokufaka i- peening yezinyathelo ezimbili ne-torsion njengezinqubo zokwelashwa kwangaphambili.
Imiphumela yokuhlaziywa kwamandla entwasahlobo isetshenziswa kuzibalo zikaGoodman kanye nejika le-SN ukuze kubikezelwe impilo yokukhathala kwe-valve yasentwasahlobo, futhi umphumela wokujula kokungasebenzi kahle empilweni yokukhathala nawo uyahlolwa.
Kulolu cwaningo, kusetshenziswe intambo yebanga le-MPa engu-2300 yebanga le-OT enobubanzi obungu-2.5 mm ukuze kuhlolwe impilo yokukhathala yesiphethu sevalvu yenjini yezimoto.Okokuqala, ukuhlolwa okuqinile kocingo kwenziwa ukuze kutholwe imodeli yayo yokuphuka kwe-ductile.
Izici zomshini zocingo lwe-OT zitholwe ekuhlolweni okuqinile ngaphambi kokuhlaziywa kwesici esinomkhawulo senqubo yokugoqa okubandayo namandla entwasahlobo.Ijika le-stress-strain lezinto ezibonakalayo lanqunywa kusetshenziswa imiphumela yokuhlolwa kwe-tensile ngesilinganiso sobunzima esingu-0.001 s-1, njengoba kuboniswe ku-fig.1. Kusetshenziswa intambo ye-SWONB-V, futhi amandla ayo okukhiqiza, amandla aqinile, i-elastic modulus ne-Poisson's ratio ingu-2001.2MPa, 2316MPa, 206GPa kanye no-0.3 ngokulandelanayo.Ukuncika kwengcindezi ku-flow strain kutholakala kanje:
Ilayisi.2 ibonisa inqubo yokuqhekeka kwe-ductile.Izinto zenza i-elastoplastic deformation ngesikhathi sokuguqulwa, futhi impahla iyancipha lapho ingcindezi entweni ifinyelela amandla ayo aqinile.Kamuva, ukudalwa, ukukhula kanye nokuhlangana kwe-voids ngaphakathi kwempahla kuholela ekubhujisweni kwempahla.
Imodeli ye-ductile fracture isebenzisa imodeli ye-deformation ebalulekile eguquliwe eguquguqukayo ecabangela umphumela wokucindezeleka, futhi i-post-necking fracture isebenzisa indlela yokuqoqa umonakalo.Lapha, ukuqaliswa komonakalo kuvezwa njengomsebenzi wobunzima, i-stress triaxiality, kanye nezinga lokucindezeleka.I-triaxiality yokucindezeleka ichazwa njengenani elilinganiselwe elitholakala ngokuhlukanisa ukucindezeleka kwe-hydrostatic okubangelwa ukuguqulwa kwezinto kuze kufike ekubunjweni kwentamo ngokucindezeleka okuphumelelayo.Endleleni yokuqongelela umonakalo, ukucekelwa phansi kwenzeka lapho inani lomonakalo lifinyelela ku-1, futhi amandla adingekayo ukuze kufinyelelwe inani lomonakalo ongu-1 achazwa njengamandla okubhubhisa (Gf).Amandla okuphuka ahambisana nesifunda sejika langempela lokususwa kwengcindezi yezinto ezibonakalayo kusukela entanyeni ukuya esikhathini sokuphuka.
Endabeni yezinsimbi ezivamile, kuye ngokuthi imodi yokucindezeleka, ukuphuka kwe-ductile, ukuphuka kwe-shear, noma ukuhlukana kwemodi exubile kwenzeka ngenxa ye-ductility kanye nokuphuka kwe-shear, njengoba kuboniswe kuMfanekiso 3. iphethini yokuphuka.
Ukwehluleka kwepulasitiki kwenzeka endaweni ehambisana ne-stress triaxiality engaphezu kwe-1/3 (zone I), futhi ukuphuka kwe-fracture kanye ne-stress triaxiality kungase kuthathwe ekuhlolweni okuqinile kuma-specimens anokukhubazeka kwendawo namanotshi.Endaweni ehambisana ne-stress triaxiality engu-0 ~ 1/3 (zone II), inhlanganisela yokuphuka kwe-ductile nokuhluleka kwe-shear kwenzeka (okungukuthi ngokuhlolwa kwe-torsion. Endaweni ehambisana ne-stress triaxiality kusuka ku- -1/3 kuya ku-0 (III), ukwehluleka kwe-shear okubangelwa ukucindezelwa, nokuqina kokuphuka kanye ne-stress triaxiality kungatholwa ngokuhlolwa okucasulayo.
Ngezintambo ze-OT ezisetshenziselwa ukwakhiwa kweziphethu ze-valve yenjini, kuyadingeka ukucabangela ukuphuka okubangelwa izimo ezihlukahlukene zokulayisha ngesikhathi senqubo yokukhiqiza kanye nezimo zokufaka isicelo.Ngakho-ke, ukuhlolwa kwe-tensile kanye ne-torsion kwenziwa ukuze kusetshenziswe umbandela wokuhluleka, umphumela we-triaxiality ye-stress kumodi ngayinye yokucindezeleka wacatshangelwa, futhi ukuhlaziywa kwe-elastoplastic finite element ezinkingeni ezinkulu kwenziwa ukuze kulinganiswe ushintsho ku-triaxiality yokucindezeleka.Imodi yokucindezela ayizange icatshangelwe ngenxa yomkhawulo wokucubungula isampula, okungukuthi, ububanzi bocingo lwe-OT bungu-2.5 mm kuphela.Ithebula 1 libala izimo zokuhlola zokushuba kanye ne-torsion, kanye ne-stress triaxiality kanye ne-fracture strain, etholwe kusetshenziswa ukuhlaziywa kwezinto ezinomkhawulo.
Ukuhlukana kwezinhlobo zezinsimbi ezivamile ze-triaxial ngaphansi kwengcindezi kungabikezelwa kusetshenziswa isibalo esilandelayo.
lapho i-C1: \({\ overline{{\varepsilon}_{0}}}^{pl}\) ukusika okuhlanzekile (η = 0) kanye ne-C2: \({\ overline{{\varepsilon}_{0} } }^{pl}\) I-Uniaxial tension (η = η0 = 1/3).
Imigqa yethrendi yemodi yokucindezeleka ngayinye itholakala ngokusebenzisa amanani obunzima bokuphuka C1 kanye ne-C2 kusibalo.(2);I-C1 ne-C2 itholakala ekuhlolweni kwe-tensile kanye ne-torsion kumasampuli angenawo ukukhubazeka kwendawo.Umfanekiso 4 ubonisa i-stress triaxiality kanye ne-fracture strain etholwe ekuhlolweni kanye nemigqa yethrendi ebikezelwe isibalo.(2) Umugqa wethrendi otholwe ekuhlolweni kanye nobudlelwano phakathi kwe-stress triaxiality kanye ne-fracture strain ibonisa ithrendi efanayo.I-strain yokuphuka kanye ne-stress triaxiality yemodi yokucindezeleka ngayinye, etholwe ekusetshenzisweni kwemigqa yethrendi, isetshenziswe njengemibandela yokuphuka kwe-ductile.
I-break energy isetshenziswa njengempahla yokunquma isikhathi sokuphuka ngemuva kokugoqa futhi ingatholakala ekuhlolweni okuqinile.Amandla okuphuka ancike ekubeni khona noma ukungabikho kwemifantu ebusweni bezinto ezibonakalayo, ngoba isikhathi sokuphuka sincike ekugxilweni kwezingcindezi zendawo.Amanani 5a-c abonisa amandla okuphuka kwamasampula angenawo amaphutha angaphezulu namasampuli anamanotshi angu-R0.4 noma angu-R0.8 avela ekuhlolweni okuqinile kanye nokuhlaziywa kwezinto ezinomkhawulo.Amandla okuphuka ahambisana nendawo yejika leqiniso lokususa ingcindezi ukusuka entanyeni ukuya esikhathini sokuphuka.
Amandla okuphuka kwentambo ye-OT enokulimala okuhle kwendawo abikezelwe ngokwenza uhlolo oluqinile ocingweni lwe-OT enokukhubazeka okujulile kuno-40 µm, njengoba kuboniswe ku-Fig. 5d.Izibonelo eziyishumi ezinokukhubazeka zisetshenziswe ekuhlolweni okuqinile futhi isilinganiso samandla okuphuka alinganiselwa ku-29.12 mJ/mm2.
Ukonakala kwendawo esezingeni elimisiwe kuchazwa njengesilinganiso sokujula kwesici kuya kububanzi bocingo lwesiphethu se-valve, kungakhathaliseki ukuthi i-jometri engasebenzi kahle yocingo lwe-OT olusetshenziswa kanjani ekwenzeni iziphethu zamavalvu ezimoto.Amaphutha ezintambo ze-OT angahlukaniswa ngokusekelwe ku-orientation, ijometri, nobude.Ngisho nokujula okufanayo kwesici, izinga lokucindezeleka elisebenza endaweni engalungile entwasahlobo liyahlukahluka kuye ngokuthi i-geometry kanye nokuma kwesici, ngakho-ke i-geometry kanye nokuma kwesici kungathinta amandla okukhathala.Ngakho-ke, kuyadingeka ukucabangela i-geometry kanye nokuma kwezinkinga ezinomthelela omkhulu empilweni yokukhathala kwentwasahlobo ukuze kusetshenziswe imibandela eqinile yokulawula ukonakala kwendawo.Ngenxa yokwakheka okuhle okusanhlamvu kocingo lwe-OT, impilo yayo yokukhathala izwela kakhulu ekuqashweni.Ngakho-ke, isici esibonisa ukugxila okuphezulu kakhulu kwengcindezi ngokuya ngejometri kanye nokuma kwesici kufanele kusungulwe njengesici sokuqala kusetshenziswa ukuhlaziya izinto ezinomkhawulo.Emkhiwaneni.6 ikhombisa amandla aphakeme kakhulu angama-2300 MPa ekilasi lamavalvu emithombo yezimoto asetshenziswe kulolu cwaningo.
Amaphutha angaphezulu ocingo lwe-OT ahlukaniswe abe yiziphambeko zangaphakathi kanye namaphutha angaphandle ngokuya nge-axis yasentwasahlobo.Ngenxa yokugoba ngesikhathi sokugoqa okubandayo, ingcindezi ecindezelayo kanye nengcindezi yokuqina yenza ngaphakathi nangaphandle kwentwasahlobo, ngokulandelana.Ukuphuka kungabangelwa ukukhubazeka okungaphezulu okuvela ngaphandle ngenxa yokucindezeleka okuqinile ngesikhathi sokugoqa okubandayo.
Empeleni, intwasahlobo ingaphansi kokucindezelwa ngezikhathi ezithile nokuphumula.Ngesikhathi sokucindezelwa kwentwasahlobo, izintambo zensimbi ziyajikajika, futhi ngenxa yokugxila kokucindezeleka, ukucindezelwa kwe-shear ngaphakathi kwentwasahlobo kuphakeme kunokucindezeleka kwe-shear ezungezile7.Ngakho-ke, uma kukhona ukukhubazeka okungaphezulu ngaphakathi kwentwasahlobo, amathuba okuphuka kwentwasahlobo makhulu kakhulu.Ngakho-ke, uhlangothi lwangaphandle lwentwasahlobo (indawo lapho ukwehluleka kulindeleke khona ngesikhathi sokwenziwa kwentwasahlobo) kanye nohlangothi lwangaphakathi (lapho ukucindezeleka kukhulu kakhulu ekusetshenzisweni kwangempela) kubekwe njengezindawo zokukhubazeka okungaphezulu.
Ijiyomethri enesici esingaphezulu semigqa ye-OT ihlukaniswe yaba yi-U-shape, i-V-shape, i-Y-shape, kanye ne-T-shape.Uhlobo lwe-Y kanye nohlobo lwe-T luba khona ikakhulukazi ekushiyekeni kwezinto ezingavuthiwe, futhi uhlobo lwe-U nohlobo lwe-V luvela ngenxa yokuphathwa budedengu kwamathuluzi enqubweni yokugoqa okubandayo.Mayelana nejiyomethri yokukhubazeka okungaphezulu kwezinto ezingavuthiwe, amaphutha amise okuka-U avela ngenxa yokuguqulwa kwepulasitiki okungajwayelekile ngesikhathi sokuginqika akhubazeka abe yiziphambeko zomthungo ezimise okuka-V, okumise okuka-Y kanye no-T ngaphansi kwe-multi-pass stretching8, 10.
Ngaphezu kwalokho, amaphutha amise okuka-V, okumise okuka-Y kanye no-T anokuthambekela okuphakeme kwenotshi endaweni engaphezulu azobhekana nokugxilwa kwengcindezi ephezulu ngesikhathi sokusebenza kwentwasahlobo.Ama-valve springs ayagoba ngesikhathi sokugoqa okubandayo futhi asonte ngesikhathi sokusebenza.Ukugxiliswa kwengcindezi kokukhubazeka okumise okuka-V nokumise okuka-Y okunokugxila okuphezulu kwengcindezi kuqhathaniswe kusetshenziswa ukuhlaziya izinto ezinomkhawulo, i-ABAQUS - isofthiwe yokuhlaziya izinto ezinomkhawulo wokuthengisa.Ubudlelwano bokucindezeleka nokucindezeleka buboniswa kuMfanekiso 1 kanye Nezibalo 1. (1) Lokhu kulingisa kusebenzisa isici esingunxande esinamanodi amane angama-dimensional (2D), futhi ubude obuncane bohlangothi lwe-elementi bungu-0.01 mm.Kumodeli yokuhlaziya, amaphutha amise okwe-V kanye no-Y anobubanzi obungu-0.5 mm kanye nomthambeka wesici esingu-2 ° asetshenziswe kumodeli ye-2D yocingo enobubanzi obungu-2.5 mm nobude obungu-7.5 mm.
Emkhiwaneni.I-7a ibonisa ukugxila kwengcindezi egobile ekugcineni kwesici ngasinye lapho umzuzu wokugoba ongu-1500 Nmm usetshenziswa kuzo zombili iziphetho zocingo ngalunye.Imiphumela yokuhlaziywa ibonisa ukuthi ukucindezeleka okukhulu kwe-1038.7 kanye ne-1025.8 MPa kwenzeka phezulu kweziphambeko ezimise okwe-V kanye no-Y, ngokulandelanayo.Emkhiwaneni.I-7b ibonisa ukugxila kwengcindezi phezulu kwesici ngasinye esibangelwa ukuhlukumeza.Uma uhlangothi lwesobunxele luboshiwe futhi i-torque engu-1500 N∙mm isetshenziswa ngakwesokudla, ukucindezeleka okufanayo okuphezulu kwe-1099 MPa kwenzeka kumathiphu okukhubazeka okumise okwe-V kanye no-Y.Le miphumela ibonisa ukuthi ukukhubazeka kohlobo lwe-V kubonisa ingcindezi ephakeme yokugoba kunokulimala kohlobo lwe-Y lapho kunokujula okufanayo kanye nomthambeka wesici, kodwa ahlangabezana nengcindezi efanayo yokuguquguquka.Ngakho-ke, amaphutha asendaweni amise okuka-V futhi amise okuka-Y ngokujula okufanayo kanye nomthambeka wesici angenziwa ngendlela evamile abe anomumo ongu-V anokucindezeleka okuphezulu okuphezulu okubangelwa ukugxila kwengcindezi.Isilinganiso sikasayizi wesici sohlobo lwe-V sichazwa ngokuthi α = w/h kusetshenziswa ukujula (h) nobubanzi (w) kohlobo lwe-V nokukhubazeka kohlobo lwe-T;ngakho-ke, ukukhubazeka kohlobo lwe-T (α ≈ 0) esikhundleni salokho, i-geometry ingachazwa ngesakhiwo sejometri sesici sohlobo lwe-V.Ngakho-ke, ukukhubazeka kohlobo lwe-Y kanye nohlobo lwe-T kungenziwa ngokujwayelekile ngokukhubazeka kohlobo lwe-V.Kusetshenziswa ukujula (h) nobude (l), isilinganiso sobude sichazwa ngenye indlela ngokuthi β = l/h.
Njengoba kuboniswe kuMfanekiso 811, izikhombisi-ndlela zokukhubazeka okungaphezulu kwezintambo ze-OT zihlukaniswa zibe izikhombisi-ndlela ze-longitudinal, transverse kanye ne-oblique, njengoba kuboniswe kumfanekiso 811. indlela.
Emkhiwaneni.I-9a ibonisa imodeli yokuhlaziya ukucindezeleka kwe-valve entwasahlobo.Njengesimo sokuhlaziya, intwasahlobo yayicindezelwe ukusuka ekuphakameni kwamahhala kwe-50.5 mm kuya ekuphakameni okunzima kwe-21.8 mm, ukucindezeleka okukhulu kwe-1086 MPa kwakhiqizwa ngaphakathi kwentwasahlobo, njengoba kuboniswe ku-Fig. 9b.Njengoba ukwehluleka kweziphethu zangempela zamavalvu enjini kwenzeka ikakhulukazi phakathi nentwasahlobo, ukuba khona kokukhubazeka kwangaphakathi kulindeleke ukuthi kuthinte kakhulu ukuphila kokukhathala kwentwasahlobo.Ngakho-ke, amaphutha angaphezulu eziqondisweni ze-longitudinal, transverse kanye ne-oblique zisetshenziswa ngaphakathi kwemithombo ye-valve yenjini kusetshenziswa amasu e-sub-modeling.Ithebula lesi-2 libonisa ubukhulu bokulimala kwendawo kanye nengcindezi enkulu ohlangothini ngalunye lwesici ekucindezelweni okuphezulu kwentwasahlobo.Izingcindezi eziphakeme kakhulu zabonwa ohlangothini olunqamulayo, futhi isilinganiso sokucindezeleka eziqondisweni ze-longitudinal ne-oblique eya endaweni ephambeneyo silinganiselwa ku-0.934-0.996.Isilinganiso sokucindezeleka singanqunywa ngokumane sihlukanise leli nani ngengcindezi enkulu eguquguqukayo.Ukucindezeleka okukhulu entwasahlobo kwenzeka phezulu kwesici ngasinye sobuso, njengoba kuboniswe ku-Fig. 9s.Amanani engcindezi aqashelwa ku-longitudinal, transverse, kanye nezikhombisi-ndlela ezitshekile angu-2045, 2085, kanye no-2049 MPa, ngokulandelana.Imiphumela yalokhu kuhlaziya ibonisa ukuthi ukonakala kwendawo ephambanayo kunomphumela oqondile kakhulu ekuphileni kokukhathala kweziphethu zamavalvu enjini.
Isici esimise okuka-V, okucatshangwa ukuthi sithinta ngqo kakhulu impilo yokukhathala yesiphethu se-valve yenjini, sakhethwa njengesici sokuqala socingo lwe-OT, futhi isiqondiso esiphambene sakhethwa njengendlela yesici.Lesi sici asenzeki ngaphandle kuphela, lapho isiphethu se-valve yenjini saphuka khona ngesikhathi sokukhiqizwa, kodwa futhi nangaphakathi, lapho ukucindezeleka okukhulu kwenzeka ngenxa yokuhlushwa ukucindezeleka ngesikhathi sokusebenza.Ukujula okukhulu kwephutha kusethelwe ku-40 µm, okungatholwa ngokutholwa kwephutha lamanje le-eddy, futhi ukujula okuncane kusethelwe ekujuleni okuhambisana no-0.1% wedayamitha yentambo engu-2.5 mm.Ngakho-ke, ukujula kwesici kusuka ku-2.5 kuya ku-40 µm.Ukujula, ubude, nobubanzi bamaphutha ngesilinganiso sobude obungu-0.1~1 kanye nesilinganiso sobude obungu-5~15 kwasetshenziswa njengeziguquko, futhi umphumela wabo emandleni okukhathala entwasahlobo wahlolwa.Ithebula lesi-3 libala izimo zokuhlaziya ezinqunywa kusetshenziswa indlela yendawo yokuphendula.
Iziphethu zamavalvu enjini yezimoto zakhiwe ngokusonteka okubandayo, ukushisa, ukuqhunyiswa kwesibhamu kanye nokusetha ukushisa kwentambo ye-OT.Izinguquko ezinkingeni ezingaphezulu ngesikhathi sokwenziwa kwentwasahlobo kufanele zicatshangelwe ukuze kuhlolwe umthelela wezinkinga zakuqala ezintanjeni ze-OT empilweni yokukhathala kweziphethu zamavalvu enjini.Ngakho-ke, kulesi sigaba, ukuhlaziywa kwezinto ezinomkhawulo kusetshenziselwa ukubikezela ukuwohloka kokonakala kwendawo ye-OT ngesikhathi kukhiqizwa intwasahlobo ngayinye.
Emkhiwaneni.I-10 ikhombisa inqubo yokugoqa ebandayo.Phakathi nale nqubo, intambo ye-OT ifakwa kumhlahlandlela wocingo yi-feed roller.Umhlahlandlela wocingo uyaphakela futhi usekele ucingo ukuvimbela ukugoba ngesikhathi sokwenza.Intambo edlula kumhlahlandlela wocingo igotshwa yinduku yokuqala neyesibili ukwenza isiphethu sekhoyili esinobubanzi obufunwayo bangaphakathi.I-spring pitch ikhiqizwa ngokuhambisa ithuluzi lokunyathela ngemva kokuphenduka okukodwa.
Emkhiwaneni.I-11a ibonisa imodeli ye-elementi enomkhawulo esetshenziselwa ukuhlola ushintsho ku-geometry yokukhubazeka kwendawo ngesikhathi sokugoqeka okubandayo.Ukwakhiwa kocingo kuqedwa ngokuyinhloko yiphini elijikayo.Njengoba ungqimba lwe-oxide ebusweni bocingo lusebenza njengesithambiso, umphumela wokungqubuzana we-feed roller awunaki.Ngakho-ke, kumodeli yokubala, i-feed roller kanye ne-wire guide yenziwa lula njenge-bushing.I-coefficient yokungqubuzana phakathi kwentambo ye-OT nethuluzi lokwakha isethelwe ku-0.05.Indiza yomzimba eqinile ye-2D kanye nezimo zokulungisa zisetshenziswa ekugcineni kwesobunxele komugqa ukuze ikwazi ukuphakelwa ngendlela engu-X ngesivinini esifanayo nesokuphakelayo roller (0.6 m/s).Emkhiwaneni.I-11b ibonisa indlela yokulingisa engaphansi esetshenziselwa ukufaka amaphutha amancane ezintanjeni.Ukuze kucatshangelwe ubukhulu bokulimala kwendawo, imodeli engaphansi isetshenziswa kabili uma kuneziphambeko ezingaphezulu ngokujula okungu-20 µm noma ngaphezulu futhi izikhathi ezintathu ngokulimala kwendawo enokujula okungaphansi kuka-20 µm.Amaphutha angaphezulu asetshenziswa ezindaweni ezakhiwe ngezinyathelo ezilinganayo.Kumodeli yonke yentwasahlobo, ubude bocingo oluqondile buyi-100 mm.Kumodeli engaphansi yokuqala, sebenzisa imodeli engaphansi engu-1 enobude obungu-3mm ukuya endaweni yobude engu-75mm ukusuka kumodeli yomhlaba wonke.Lokhu kulingisa kusebenzise i-elementi enamanodi ayisishiyagalombili enezinhlangothi ezintathu (3D).Kumodeli yomhlaba wonke kanye ne-submodel 1, ubude obuncane obuhlangothini be-elementi ngayinye ngu-0.5 no-0.2 mm, ngokulandelanayo.Ngemuva kokuhlaziywa kwe-sub-model 1, amaphutha angaphezulu asetshenziswa kumodeli engaphansi 2, futhi ubude nobubanzi be-sub-model 2 buphindwe izikhathi ezingu-3 ubude besici esingaphezulu ukuze kuqedwe ithonya lemibandela yomngcele wemodeli engaphansi, ngaphezu kwalokho, u-50% wobude nobubanzi busetshenziswa njengokujula kwemodeli encane.Kumodeli encane engu-2, ubude obuncane obuhlangothini be-elementi ngayinye bungu-0.005 mm.Kusetshenziswe ukonakala okuthile ekuhlaziyweni kwezinto ezinomkhawulo njengoba kuboniswe kuThebula 3.
Emkhiwaneni.12 ikhombisa ukusabalaliswa kokucindezeleka emifantwini yangaphezulu ngemva kokusebenza okubandayo kwekhoyili.Imodeli evamile kanye ne-submodel 1 ibonisa cishe ukucindezeleka okufanayo kwe-1076 ne-1079 MPa endaweni efanayo, okuqinisekisa ukulunga kwendlela ye-submodeling.Ukugxila kwengcindezi yendawo kwenzeka emaphethelweni omngcele we-submodel.Ngokusobala, lokhu kungenxa yemibandela yomngcele we-submodel.Ngenxa yokugxilisa ingqondo, imodeli engaphansi engu-2 enokukhubazeka kwendawo esetshenzisiwe ibonisa ingcindezi engu-2449 MPa ekugcineni kwesici ngesikhathi sokugoqa okubandayo.Njengoba kukhonjisiwe kuThebula lesi-3, amaphutha angaphezulu ahlonzwe ngendlela yokusabela asetshenziswe ngaphakathi entwasahlobo.Imiphumela yokuhlaziywa kwesici esilinganiselwe ibonise ukuthi azikho izehlakalo eziyi-13 zokukhubazeka kwendawo ehlulekile.
Ngesikhathi senqubo yokugoqa kuzo zonke izinqubo zobuchwepheshe, ukujula kokukhubazeka kwendawo ngaphakathi kwentwasahlobo kukhuphuke ngo-0.1–2.62 µm (Fig. 13a), futhi ububanzi behla ngo-1.8–35.79 µm (Fig. 13b), kanti ubude bukhuphuke ngo-0.72 –34.47 µm (Fig. 13c).Njengoba isici esiphambanayo esimise okuka-V sivalwa ngobubanzi ngokugoba phakathi nenqubo yokugoqa okubandayo, sonakaliswa sibe isici esimise okuka-V esinomqansa ongaphezu kwesici sokuqala.
Ukuguqulwa Kokujula, Ububanzi Nobude Beziphambeko Ze-OT Wire Surface Enqubweni Yokukhiqiza.
Faka okonakele ngaphandle kwentwasahlobo futhi ubikezele amathuba okuphuka ngesikhathi sokugoqa okubandayo usebenzisa i-Finite Element Analysis.Ngaphansi kwemibandela esohlwini lweThebula.3, awekho amathuba okucekelwa phansi kweziphambeko endaweni engaphandle.Ngamanye amazwi, akukho monakalo owenzekile ekujuleni kokukhubazeka okusuka ku-2.5 kuya ku-40 µm.
Ukuze ubikezele ukukhubazeka okubucayi kwendawo, ukuphuka kwangaphandle phakathi nokugoqeka okubandayo kwaphenywa ngokukhuphula ukushona kwesici ukusuka ku-40 µm kuya ku-5 µm.Emkhiwaneni.I-14 ibonisa ukuphuka eduze kokukhubazeka kwendawo.Ukuphuka kwenzeka ngaphansi kwezimo zokujula (55 µm), ububanzi (2 µm), nobude (733 µm).Ukujula okubalulekile kwesici esingaphezulu ngaphandle kwentwasahlobo kuvele kwaba ngu-55 μm.
Inqubo yokuvula isibhamu icindezela ukukhula kwe-crack futhi ikhulise impilo yokukhathala ngokudala ingcindezi eyinsalela ecindezelayo ekujuleni okuthile okuvela endaweni yasentwasahlobo;nokho-ke, kubangela ukugxila kokucindezeleka ngokwandisa ubulukhuni obungaphezulu kwentwasahlobo, ngaleyo ndlela kunciphise ukumelana nokukhathala kwentwasahlobo.Ngakho-ke, ubuchwepheshe besibili bokuvula isibhamu busetshenziselwa ukukhiqiza imithombo yamandla aphezulu ukunxephezela ukuncipha kwempilo yokukhathala okubangelwa ukwanda kobulukhuni obubangelwa ukuchama kwesibhamu.Ukuchama okunezigaba ezimbili kungathuthukisa ubulukhuni obungaphezulu, ukucindezeleka okuyinsalela okukhulu okucindezelwayo, kanye nengcindezi yensalela ecindezelayo ngenxa yokuthi ukuchama kwesibhamu kwesibili kwenziwa ngemva kokudubula kokuqala12,13,14.
Emkhiwaneni.I-15 ibonisa imodeli yokuhlaziya yenqubo yokudubula.Kwakhiwe imodeli enwebekayo yepulasitiki lapho ama-shotballs angu-25 ajikijelwa endaweni okuhloswe ngayo umugqa we-OT ukuze aqhunyiswe ngesibhamu.Kumodeli yokuhlaziya ukuqhunyiswa kokudubula, ukonakala kwendawo ocingweni lwe-OT olonakele ngesikhathi sokusongwa okubandayo kwasetshenziswa njengamaphutha okuqala.Ukususwa kokucindezeleka okuyinsalela okuvela enqubweni ebandayo yokugoqa ngokushisa ngaphambi kwenqubo yokudubula.Kusetshenziswe izici ezilandelayo ze-shot sphere: ukuminyana (ρ): 7800 kg/m3, i-elastic modulus (E) – 210 GPa, isilinganiso sika-Poisson (υ): 0.3.I-coefficient of friction phakathi kwebhola nokokusebenza isethelwe ku-0.1.Amashothi anobubanzi obungu-0.6 kanye no-0.3 mm akhishwe ngesivinini esifanayo esingu-30 m/s ngesikhathi sokudlula kokuqala nesesibili.Ngemva kwenqubo yokudubula (phakathi kwezinye izinqubo zokukhiqiza eziboniswe kuMfanekiso 13), ukujula, ububanzi, nobude bezinkinga zendawo phakathi kwentwasahlobo busukela ku- -6.79 kuya ku-0.28 µm, -4.24 kuya ku-1.22 µm, kanye -2 .59 kuya ku-1.69 µm, ngokulandelana µm.Ngenxa yokuguqulwa kwepulasitiki ye-projectile ekhishwe i-perpendicular ebusweni bezinto ezibonakalayo, ukujula kwesici kuncipha, ikakhulukazi, ububanzi besici buyancipha kakhulu.Ngokusobala, iphutha livaliwe ngenxa yokuguqulwa kwepulasitiki okubangelwa ukuchama kwesibhamu.
Ngesikhathi senqubo yokunciphisa ukushisa, imiphumela yokuncipha okubandayo kanye nokushisa okuphansi kwe-annealing kungasebenza esiphethwini se-valve yenjini ngesikhathi esifanayo.Ukulungiselelwa okubandayo kukhulisa izinga lokucindezeleka kwentwasahlobo ngokulicindezela lifike ezingeni eliphezulu kakhulu elingaba khona ekamelweni lokushisa.Kulokhu, uma i-valve injini entwasahlobo ilayishwa ngaphezu kwamandla okukhiqiza wezinto ezibonakalayo, i-valve ye-injini ye-spring plastic ikhubazekile, okwandisa amandla okukhiqiza.Ngemuva kokuguqulwa kwepulasitiki, i-valve spring iyaguquguquka, kodwa amandla okukhiqiza akhulayo ahlinzeka ngokunwebeka kwentwasahlobo ye-valve ekusebenzeni kwangempela.Ukushisa okuphansi kwe-annealing kuthuthukisa ukumelana nokushisa nokuguquka kwemithombo yama-valve asebenza emazingeni okushisa aphezulu2.
Ukukhubazeka okungaphezulu kukhubazekile ngesikhathi sokuqhuma kwesibhamu ekuhlaziyweni kwe-FE kanye nenkambu yokucindezeleka eyinsalela elinganiswa ngemishini ye-X-ray diffraction (XRD) yasetshenziswa kumodeli engaphansi 2 (Fig. 8) ukuze kucatshangelwe ukuguqulwa kweziphambeko ngesikhathi sokuncipha kokushisa.Intwasahlobo yayiklanyelwe ukuthi isebenze kububanzi obunwebekayo futhi yacindezelwa ukusuka ekuphakameni kwayo okukhululekile okungu-50.5 mm kuya ekuphakameni kwayo okuqinile okungu-21.8 mm kwase ivunyelwa ukuthi ibuyele ekuphakameni kwayo kwasekuqaleni okungu-50.5 mm njengesimo sokuhlaziya.Ngesikhathi sokunciphisa ukushisa, i-geometry yesici iyashintsha kancane.Ngokusobala, ingcindezi eyinsalela ecindezelayo engu-800 MPa nangaphezulu, edalwe ukuqhuma kwesibhamu, icindezela ukuguqulwa kokukhubazeka kwendawo.Ngemuva kokuncipha kokushisa (Umfanekiso 13), ukujula, ububanzi, nobude bezinkinga ezingaphezulu kuyahlukahluka kusuka ku- -0.13 kuya ku-0.08 µm, ukusuka ku -0.75 kuya ku-0 µm, futhi ukusuka ku-0.01 kuya ku-2.4 µm, ngokulandelanayo.
Emkhiwaneni.16 uqhathanisa ukonakala kokuma okumise okuka-U nokumise okuka-V kokushona okufanayo (40 µm), ububanzi (22 µm) nobude (600 µm).Ukushintsha kobubanzi bezinkinga ezimise okuka-U nezimise okwe-V kukhulu kunokushintsha kobude, okubangelwa ukuvala indawo yobubanzi ngesikhathi sokugoqa okubandayo kanye nenqubo yokudubula.Uma kuqhathaniswa namaphutha amise okuka-U, amaphutha amise okuka-V akheka ekujuleni okuthe xaxa futhi anemithambeka ekhuphukayo, okuphakamisa ukuthi kungenziwa indlela yokulondoloza imvelo lapho kusetshenziswa amaphutha amise okuka-V.
Lesi sigaba sidingida ukuguqulwa kwesici sokuqala emgqeni we-OT wenqubo ngayinye yokukhiqiza i-valve spring.Isici sokuqala se-OT wire sisetshenziswa ngaphakathi kwe-valve spring lapho ukwehluleka kulindeleke khona ngenxa yokucindezeleka okukhulu ngesikhathi sokusebenza kwentwasahlobo.Iziphambano zendawo ezimise okuka-V zezintambo ze-OT zenyuke kancane ukujula nobude futhi zehla ngokucijile ngobubanzi ngenxa yokugoba ngesikhathi sokugoqa okubandayo.Ukuvala ohlangothini lobubanzi kwenzeka phakathi nokuchama okunokonakala okuncane noma okungekho okuphawulekayo ngesikhathi sokusetha ukushisa kokugcina.Enqubweni yokugoqa okubandayo kanye nokuchama kwesibhamu, kukhona ukuwohloka okukhulu ohlangothini lobubanzi ngenxa yokuguqulwa kwepulasitiki.Isici esimise okwe-V ngaphakathi kwe-valve spring siguqulwa sibe isici esimise okwe-T ngenxa yokuvalwa kobubanzi phakathi nenqubo yokugoqa okubandayo.
Isikhathi sokuthumela: Mar-27-2023