Izindlela zokuhlola izinto ezihlelwe ngokupheleleyo zemashini yokuqondisa ngendlela yokugcina (EDM)

Ukubuka Kwemibala Yomfanekiso Wezinto Zomkhombo Wokusebenza Ngokwe-EDM: Ra/Rz, Isilayi Sokubuyiselwa, Nokubuka Ngokwezinye

Imibala Yomfanekiso We-Ra Ne-Rz Yokugcina Umkhombo Wokusebenza Ngokwe-EDM

Umfanekiso wemibala uyaphatha kakhulu ukusebenza nokuphila kwamazinto okusebenza ngokwe-EDM. Izinca zombili ezibalulekile—i-Ra (isilinganiso sesilinganiso semibala) ne-Rz (isilinganiso semithambo yokuqala kuze kufika emva)—sizoba nesibonelo esifanayo: i-Ra isibonisa umfanekiso wokugcina wonke, ngakho-ke i-Rz isibonisa izinto eziphakeme kakhulu zomfanekiso ozizokwenza ukuthi izinto zizihlwa ngokukhula. Kwe-EDM, umfanekiso wokugcina uyaphatha ngqo ngumthelela wokuvulwa; umthelela omncane ubuyisa umfanekiso omncane. Ithabuli elandelayo ibonisa imibala yomfanekiso we-Ra ebalulekile kakhulu kuzo zonke izigaba zokugcina ze-EDM ezibalulekile kakhulu:

Ukuhlola kwe-Rz kuyidinga kakhulu—noma uma i-Ra ibe phakathi kweminyathelo yokuqinisa, izikhumba ezide zokugcina noma izivundla zingasemthwakathini futhi zingabeka ubukhulu bezimali bokubona. Ukubhalwa kwe-profilometric kuzindawo eziphathelene nokuhlola kwezinto ezinkulu kuyasebenza kakhulu. Kumaqondo okuphelele, iminyathelo yokuvumela yizindlela zokusebenza ziyisisekelo: i-Ra ≤ 0.4 µm futhi i-Rz ≤ 2.5 µm, kuyasebenziswa ngokusebenza kahle kanye nokuvumela kahle kwezindlela zokugcina. Ukujabula kwezindlela zokusebenza—kusha kuqala kuya kusisha kwezinye—kuyasebenza kakhulu ukuthi isikhundla sokugcina sibe yilokho esifanele ngaso sonke isikhathi sokuproducwa.

Ukuchaza kwe-metallographic kwe-recast layer ne-HAZ kwezinqamuzana zokusebenza kwe-EDM

U-EDM uyaphatha ngokuzenzakalelayo indawo yomgagasi oyisilinganiso ngokuthi kubhala kanye nokubuyiselwa kahle kwesikhathi esinye. Lokhu kubhekisa kuqoqo lokubuyiselwa (umateriali owabuyiselwe kahle) emuva kwezindawo zokuhambisana komthelela (HAZ), apho umkhakha wemikro noma imiphumela yamandla ayishintshwa ngaphandle kokubhala. Iqoqo lokubuyiselwa libizwa ngokuthi libe libhuluphi, libe libhili, futhi libe libhekene nezinkinga zokubhaka kwezinkulu; i-HAZ ibhekise kuqoqo lokubhala kwezinkulu futhi libe libhekene nezinkinga zokungafanele kwezinkulu. Ukubhalwa kwezinkulu—kwenziwa ngokwesibonelo sika-ASTM E3‑11 (ukwenza isibonelo) kanye no-ASTM E407 (ukubhala kwezinkulu)—kubhekisa kuqoqo lokubhala kwezinkulu, ukubeka kwezinkulu, ukubhala kwezinkulu, nokubhala kwezinkulu ukuze kubonwe lezi qoqo ngokubona kwezinkulu noma ngokubona kwe-SEM.

Ukubhalwa kwezilinganiso zokubhala kwenziwa emaphakathini amaningi kusuka kumfanekiso otholakile, nokubhalwa kweminye yezinto ezihlukene: okuncane kakhulu, okude kakhulu, nokudla ngokusebenzisa. Kuzo izindlela zokusebenza eziphambili kwezinkinga zokuphatha, umsebenzi wasezindustria ubhekisela ukubhala kwe-recast layer ku-<10 µm; ukubhekisa okuphelele (<5 µm) kuyasebenza lapho akukho ukusebenzisa kwezinye izindlela emuva kwezinye. Uma kubhala kakhulu kulezi zikhathi, kufuneka kuhlelwe izinkampani (isibonelo: ukunciphisa isikhathi sokuphuma kwe-pulse noma ukunciphisa ukungenisa), noma ukusebenzisa izindlela zokuhlela isilawuli. Kuyisidingo esikhulu ukuthi kubhalwe ukuthi kukhona ukuphazimula, ukuthi kunezinkumbulo, noma ukuthi kunezinkumbulo zokuphazimula kusuka kwe-recast layer—lezi zinto ziyasiza kakhulu ekuphazimuleni kwezinkinga zokuphatha futhi kufuneka kuzwakalwe kabusha ngaphambi kokuthunyelwa.

Ukubona nokubona ngokubanzi njengokuhlola okukhula okokuqala lokubona izinkinga zomfanekiso wesilawuli se-EDM

Ukubuka kwezinto ngokwezinye nezinkambo zokubuka kungumqondo wokugcina okungahleli, okuncanyana ukuthi wokugcina kwesikhathi esikade kusukela ekupheleni kwezinhlelo zokubhekisa ngokuphelele. Kufakwa phakathi kokubhekiswa kwezinhlelo zokubhekisa ngokuphelele kanye nokubhekiswa ngokusebenzisa izibonelo ezingu-10–30×, lokhu kubonisa izinkinga ezingaphezulu—kodwa kuzo kufaka ukubonwa kwezinkambu, ukubonwa kwezinkambu zokubonwa, ukubonwa kwezinkambu zokubonwa, ukubonwa kwezinkambu zokubonwa, noma ukubonwa kwezinkambu zokubonwa—okubonisa ukungasemthethweni kwezinhlelo (isibonelo, ukungasemthethweni kwezinhlelo zokubhekisa, ukungasemthethweni kwezinhlelo zokubhekisa, noma ukungasemthethweni kwezinhlelo zokubhekisa). Ukubonwa kwezinkambu zokubonwa kwezinkambu zokubonwa kungabonisa ukuthi kukhona ukubonwa kwezinkambu zokubonwa; izinkambu zokubonwa ezingu-EDM zokubonwa kungabonisa ukuthi kukhona ukubonwa kwezinkambu zokubonwa noma ukubonwa kwezinkambu zokubonwa.

Le-kuhlanisa leli kufunda kusiza ukuthi kubhekwe ngokushesha izinto ezingavumeleki, okunika ukukhathazeka kokuthenga i-CMM noma isikhathi se-profilometer. Ukubhala kwe-digital ekubeni nezindlela zokubheka zokulinganisa kusiza ukuthi ababhekhi bafane kuzo zonke izinsizakwane nezinkambo. Yiziphi na izinyathelo ezibonakalayo ukuthi zinamaphuzu, amaqhina, noma iziqu zokubonakala okungafanele ngokwesifundo esisodwa sokubheka kuzo kubhekwa futhi kubhekwa kabusha noma kubhekwa ngokungabiyo. Uma kubhekwa ngokubheka kwezinyathelo ezinamandla emfanekisweni, ukubheka kwezinyathelo kusiza ukuthi umsebenzi uhlale kahle—kuphela izinyathelo ezifana nalezi zokubheka kokuqala ziyaphinda kubhekwa ngokuvamile—okunciphisa izinkinga ngaphandle kokuthatha indlela yokuhlinzekisa ubukhulu.

Ukubheka kwezilinganiso nezilinganiso zokubheka kwezinyathelo zokusebenza kwe-EDM ngokusebenzisa i-CMM nezinyathelo zokubheka ngokwezinye izinye

Ukubheka kwezilinganiso ezibalulekile: ubude bekhuluma, ububanzi be-slot, nokubheka kwezinye izinye

Amaphakathi we-EDM ayadinga ukuboniswa kwezinkulungwane zezinkulungwane zezinkulungwane zezinkulungwane—kukhona izinkulungwane zezinkulungwane, izinkulungwane zezinkulungwane, nezinkulungwane zezinkulungwane—lapho izilinganiso ezincinci kakhulu njenge-±0.002 mm zingahleli ukuthi zihambisane, zisebenze noma zihlanganise. Amashini okulinganisa okuphakathi (CMMs) ayathumela ukulinganisa okutholakala ngokuthi yiliphi iphuzu lezinye izinyathelo, futhi ayahlukanisa isimo sokubuyiselwa ngokugcina isithembiso se-CAD. Ukulinganisa kwesibhakabhaka—kukhona amaprojektho weprofayili, amashini okuscannga esikhundleni sesibhakabhaka, namashini okuscannga wesithandwa—ayagcinwa ngokushesha nokungathathi isikhundleni isikhundleni sokulinganisa kwe-CMM, ikhona ngokuvamile kumaqondo okufana noma kumaqondo okuthula.

Ukusebenzisa kahle kwe-CMM nezinhlangano zezinkampani zokubona kusenza ukuthi kufakelwe konke: i-CMM ibhekise kwezinhlobo zemiphakathi, izinkinga zokuhambisana, nezinhlobo zokulandela i-GD&T; izinkampani zokubona zisiza kakhulu ekuboneni konke okuphakathi kwezinhlobo zokubonwa, ukubonwa kwemiphakathi yezihlangothi, nokubonwa kwemiphakathi yokubonwa okukhangelwa ngokubonwa kwezihlangothi noma kwezinhlobo zokubonwa okuzikhipha ukubonwa kwezihlangothi noma ukubonwa kwezinhlobo zokubonwa okuzikhipha ukubonwa kwezihlangothi. Lokhu kucatshangwa kakhulu kuma-electrodes, ama-mold inserts, nezinhlobo zase-aviation—lapho ukubonwa kwezinhlobo zokubonwa kuyisibonelo sokukhangelwa kwezinhlobo zokubonwa ezizokwenzeka emuva kwezinhlobo zokubonwa.

Ukuthembana kwezinhlobo zokubonwa (Ukuthembana kwezinhlobo zokubonwa, Ukuthembana kwezinhlobo zokubonwa, Ukuthembana kwezinhlobo zokubonwa) nokuthembana kwezinhlobo zokubonwa

Ngaphandle kwezinkinga zokulinganisa izinsizakalo, iziparti ze-EDM kufanele ziphathiswe ngamathuba amakhulu okulinganisa izinsizakalo zezinhlobo—njengokulinganisa ukungafani kwezihlangothi nezihlangothi zokubhekana, ukungafani kwezihlangothi ezide, noma ukulinganisa ukungafani kwezihlangothi zokubhekana. Iziprogram zesiqondiso se-CMM zisithola lezi zilinganiso zezinhlobo zezinsizakalo ngokusebenzisa iziqondiso esikhulu sezinkamba, zilahla ukulinganisa ukungafani, isimo, nokuthi iphi indawo yazo ngokulinganisa nokuthi kuyini okwenzeka kuzo. Ukulandela kwesikhathi sokuphela (FAI) usebenzisa lezi zindlela ukuvelisa irekodi yonke, eyayisibonelo, yezinsizakalo zonke eziphathiswa, ekwenzeni isibonelo esivumelwayo sokuphela kwezinto ezizokuphela.

Isibonelo, ukungafani kusilwa ngokulinganisa ubude bekhanda kwezindawo eziningi zokubhekana; ukungafani kusilwa ngokulinganisa ukungafani kwezihlangothi zokubhekana kwezihlangothi zokubhekana nezihlangothi zokubhekana. Lezi zilungiselelo ziyisigaba esikhulu sokuphela kwezinto ezisetyenziswa kwezinhlobo zokugcina ezinkulu noma kwezinhlobo zokuhlanganisa ezikhulu—apho ukungafani okuncane kuphela kungalungiselela ukungabhekana, ukuphela kancane, noma ukungasebenzi.

Imiphumela Yokuqhubeka Emva Kwe-EDM Kusukela Kuqinisekiso Lwemiphumela Neqinisekiso Lokusebenza Kwemithombo

Ukuthintela, Ukupholisa Noma Ukuvimbela Umkhawulo Wokugcina Ukuhambisana Nokuguqula Imiphumela Yomkhawulo Wokugcina Emva Kwezindlela Zokusebenza Zase-EDM

Izindlela Zokusebenza Emva Kwe-EDM zihambisana ngokuphelele imiphumela yokugcina umkhawulo—futhi kufanele ziqinisekiswe kabusha ukuthi ziyafanele kuzo zonke izimpendulo. Ukuthintela kususa amaglobuli amathuba okugcina kodwa izindlela eziphambili zingalibeka amaphakathi amancane okugcina okuyenza ukuthi i-Ra ibe phakade. Ukupholisa okubhekene ngezimali kuncane ukuthi i-Ra ishange kusukela ku~3.2 µm ku<0.4 µm futhi kususa amacrack amancane okugcina umkhawulo—kodwa ukupholisa okungafanele kungalibeka ukuthi izinyango zihlukwe futhi kungalibeka ukuthi izinto zingahlanganisi kakhulu. Ukuvimbela umkhawulo kwi-200–300 °C kuncane umkhawulo wokugcina wokuphambuka kwezinye izinyango ngaphezu kwe-70 %, kuhlela ukuthi izinto zibe yisibonelo esihle futhi kuvimbela ukuthi kubhekene nokugcina okungafanele.

Ngoba ngalinye elinye lezindlela ziyagcina iziphakamiso ezizimiselwe ngaprofilometry ne-metallography, iziqhelo zesikhelelo kufanele zihlale zilungiselela ukuzibonisa okugcwele kwe-Ra/Rz nokubhala kwesikhumba sokubuyiselwa. Ukuvumwa kokugcina akukho kusikhelelo sase-EDM—kodwa kusikhelelo sesiqhelo esifika kumsebenzisi wesha.

Ukuhlanza Kwesikhumba Nokuhlanganisa Kwezinkundla Zokuphatha Ngokwesikhumba Sezinhlobo Zesi-EDM

Ukuchaza kwezinhlobo zesi-EDM kusebenza kakhulu ekuthinteni ukuphatha kwesikhumba—kubhekwa kahle ngokuhlanganisa kwezinkundla zokuphatha nezinkundla zezimfihlo ezingaphansi. Nakuba isikhumba sokubuyiselwa sikhuluma ngokuphakamisa kwezinkundla zokuphatha ngokuphakamisa kwe-20–40 % kulomkhulu wokuphatha, ububi bakho bokuphatha kubeka kona indawo eyinkulu yokuvula kwemithambo phakathi kwezinqumo. Lukas et al. (2024) babonisa ukuthi ukuphatha kwezimfihlo emuva kwe-EDM kubiza ukuphatha kwesikhumba sokuphatha ngokuphakamisa kwe-40 % ngaphezu kwalokho kusikhelelo sase-EDM, futhi ukupholisa kunciphisa ukuguqula kwesikhumba sokuphatha ngokuphatha ngokuphakamisa ngokuphakamisa kwezinkundla zokuphatha ngokuphakamisa ngokuphakamisa kwezinkundla zokuphatha.

Kubonakala ukuthi kunezinhlobo zokuhlanganisa okucacile: izinyathelo eziyisisekelo ezifika emva kwe-Ra ≤ 0.8 µm kanti ezibonisa ukuthi ubunzima bezinkambu zokugcina okuphansi nokukhula kwezinkambu zokugcina okuphansi kuzoba yinkimbela yokugcina kokufana ngokwesikhathi ngokuphakeme kwe-25 %. Lokhu kubonisa ukuthi ubunzima bezinyathelo—kungakhathali ukuthi kubonakala kahle—kuyisisekelo sokubonakalisa ukusebenza kahle. Ukusebenzisa i-EDM emva kwalokho akuyiyo kuphela ukuchitha; kuyinto eyenzelwa ngokuphelele ekuboneni ukuthi iphrojekthi iyasebenza kahle futhi iyasebenza ngokuphelele.

Imibuzo Evame Ukubuzwa

Yini umbono wokuthi i-Ra ne-Rz zingaba yimiphi?

I-Ra ne-Rz ziyizindlela zokuhlola ubunzima bezinyathelo. I-Ra ihlola ubunzima bezinyathelo ngokujwayelekile, ngakho-ke i-Rz ibonisa izimo ezihlukene kakhulu ezinokuthinta ukuthi iphrojekthi iyasebenza kahle ngokuphakeme. Labo babili bahlola ubunzima bezinyathelo emva kwe-EDM.

Yini ukuthi ukubhalwa kwezinyathelo zokubuyiselwa kubhalwa njani?

Ukubhalwa kwezinyathelo zokubuyiselwa kubhalwa ngokusebenzisa izindlela zokubhalwa kwezinkambu, kufaka ukuthi kubhalwa kwezinyathelo zokubuyiselwa, ukuthi kubhalwa kwezinyathelo zokubuyiselwa, nokubhalwa ngokusebenzisa isikhombi. Izindlela zokusebenza kwezindustria zihlola ukuthi ukubhalwa kwezinyathelo zokubuyiselwa kungafana nge-<10 µm noma kuncane kakhulu kumaqembu okuphakeme.

Ungapha ukuthi ukubheka ngokwezinye izinkomba kuyasebenza njani ekukhokhelweni kwe-EDM?

Ukubheka ngokwezinye izinkomba kusebenza njengendlela yokubheka kahle ukuthola izinkinga njengezinkinga zokuphakama, isibonelo sokungafanele kwezinhlobo, noma izinkinga zokugqamisa, okunquma ukuthi iziqephu esingazange zibe yizinkinga ziyofika emaphakathini okukhokhela okuphambili.

Ukuthi ukuprosesa kusukela kwe-EDM kufaka kini ekuboneni kwesikrini?

Izindlela zokuprosesa kusukela kwe-EDM njengezindlela zokuchitha noma ukuvimbela ukuzimisa isikrini sokuboneni, ukuboneni kwe-Ra, ubude bekhotho lokubuyisela, nokuzimisa ukuzimisa. Lezi zindlela zinconywa kakhulu ukuthi iziqephu ziyasebenza kahle futhi ziyabona ukuthi zihlale kahle.

Kungani i-CMM nezindlela zokuboneni ngokwezinye izinkomba zinconywa kakhulu ekuboneni kwezinqumo zwe-EDM?

I-CMM inikeza ukuboneni okuphelele kwezinhlobo nezinhlobo zezindawo, ngakho-ke ukuboneni ngokwezinye izinkomba kubonisa izinhlobo ngokushesha. Ukusebenzisa lezi zimbili kunezinkambo zokuboneni kahle kwezinqumo zokuphambili zwe-EDM.