Uhlalutyo loKwakhiwa kunye nokuqhekeka koKwahlulwa kwePhosphorus kwiCarbon Structural Steel
Okwangoku, iinkcukacha eziqhelekileyo zeentonga zentsimbi yesinyithi kunye neebhari zekhabhoni ezibonelelwa ziifektri zentsimbi zasekhaya yi-φ5.5-φ45, kwaye uluhlu oluvuthiweyo yi-φ6.5-φ30. Kukho iingozi ezininzi ezisemgangathweni ezibangelwa kukwahlulwa kwe-phosphorus kwizixhobo ezincinci zentsimbi kunye neebhari. Masithethe ngempembelelo yokwahlulwa kwe-phosphorus kunye nohlalutyo lokwakheka kweentanda ukuze ubhekisele kuzo.
Ukongezwa kwe-phosphorus kwisinyithi kunokuvala ngokulinganayo ummandla wesigaba se-austenite kumzobo wesigaba se-iron-carbon. Ke ngoko, umgama phakathi kwe-solidus kunye ne-liquidus kufuneka wandiswe. Xa intsimbi equlethe i-phosphorus ipholisiwe ukusuka kulwelo ukuya kwi-solid, kufuneka idlule kuluhlu olubanzi lobushushu. Izinga lokusasazwa kwe-phosphorus kwisinyithi licotha. Ngeli xesha, intsimbi enyibilikisiweyo enoxinzelelo oluphezulu lwe-phosphorus (indawo yokunyibilika ephantsi) izaliswa kwizikhewu phakathi kwe-dendrites yokuqala eqinileyo, ngaloo ndlela yenze ukwahlukana kwe-phosphorus.
Kwinkqubo yokuphuma kwe-cold heading okanye i-cold extrusion, iimveliso eziqhekekileyo zihlala zibonwa. Ukuhlolwa kunye nohlalutyo lwe-metallographic lweemveliso eziqhekekileyo kubonisa ukuba i-ferrite kunye ne-pearlite zisasazwe ngama-band, kwaye umcu wesinyithi omhlophe unokubonakala ngokucacileyo kwi-matrix. Kwi-ferrite, kukho i-intermittently light grey sulfide inclusions kule matrix ye-ferrite efana ne-band. Esi sakhiwo esifana ne-band esibangelwa kukwahlulwa kwe-sulfur phosphide sibizwa ngokuba yi-"ghost line". Oku kungenxa yokuba indawo etyebileyo ye-phosphorus kwindawo enokwahlulwa okukhulu kwe-phosphorus ibonakala imhlophe kwaye ikhanya. Ngenxa yomxholo ophezulu we-phosphorus webhanti emhlophe nekhanyayo, umxholo we-carbon kwibhanti emhlophe neqaqambileyo etyebileyo ye-phosphorus uyancitshiswa okanye umxholo we-carbon umncinci kakhulu. Ngale ndlela, iikristale ze-columnar ze-continuous casting slab ziphuhliswa zisiya embindini ngexesha lokuphoswa okuqhubekayo kwebhanti etyebileyo ye-phosphorus. Xa i-billet iqina, ii-austenite dendrites ziqala ukutsalwa kwintsimbi enyibilikisiweyo. I-phosphorus kunye ne-sulphur ezikulezi dendrites ziyancipha, kodwa intsimbi enyibilikisiweyo yokugqibela ityebile kwizinto zokungcola ze-phosphorus kunye ne-sulphur, eziqina phakathi kwe-dendrite axis, ngenxa yomxholo ophezulu we-phosphorus kunye ne-sulphur, i-sulphur iya kwenza i-sulfide, kwaye i-phosphorus iya kunyibilika kwi-matrix. Akulula ukuyisasaza kwaye inefuthe lokukhupha ikhabhoni. I-carbon ayinakunyibilika ngaphakathi, ngoko ke ukujikeleza isisombululo se-phosphorus esiqinileyo (Amacala ebhendi emhlophe ye-ferrite) anomxholo ophezulu wekhabhoni. I-carbon element kumacala omabini ebhendi ye-ferrite, oko kukuthi, kumacala omabini endawo etyebiswe yi-phosphorus, ngokulandelelana yenza ibhendi encinci, engapheliyo ye-pearlite ehambelana nebhendi emhlophe ye-ferrite, kunye nezicubu eziqhelekileyo ezikufutshane. Xa i-billet ishushu kwaye icinezelwe, imingxunya iya kwanda kwicala lokucubungula. Kungenxa yokuba ibhendi ye-ferrite ine-phosphorus ephezulu, oko kukuthi, ukwahlulwa kwe-phosphorus okunzulu kukhokelela ekwakhiweni kwesakhiwo sebhendi ye-ferrite ebanzi nekhanyayo, enesinyithi esicacileyo Kukho imicu engwevu ekhanyayo ye-sulfide kwibhendi ebanzi nekhanyayo yomzimba we-element. Le bhendi ye-ferrite etyebileyo ene-phosphorus enemigca emide ye-sulfide yileyo siyibiza ngokuba yi-"ghost line organization" (jonga uMfanekiso 1-2).
Umfanekiso 1 Intambo ye-Ghost kwintsimbi yekhabhoni SWRCH35K 200X
Umfanekiso 2 Intambo ye-Ghost kwintsimbi yekhabhoni engenanto i-Q235 500X
Xa intsimbi ishushu, logama nje kukho ukwahlulwahlulwa kwe-phosphorus kwi-billet, akunakwenzeka ukufumana isakhiwo esilinganayo. Ngaphezu koko, ngenxa yokwahlulwahlulwa okukhulu kwe-phosphorus, kuye kwenziwa isakhiwo "se-ghost wire", esiya kunciphisa ngokuqinisekileyo iipropati zoomatshini zezinto.
Ukwahlulwa kwe-phosphorus kwintsimbi yekhabhoni kuqhelekile, kodwa inqanaba lahlukile. Xa i-phosphorus yahlulwe kakhulu (isakhiwo "somgca we-ghost" sibonakala), siya kuzisa iziphumo ezimbi kakhulu kwintsimbi. Ngokucacileyo, ukwahlulwa okukhulu kwe-phosphorus yeyona nto ibangela ukuqhekeka kwezinto ngexesha lenkqubo yokubanda. Ngenxa yokuba iinkozo ezahlukeneyo kwintsimbi zinomxholo we-phosphorus owahlukileyo, izinto zinamandla nobunzima obahlukeneyo; kwelinye icala, kukwenza izinto zivelise uxinzelelo lwangaphakathi, kuya kukhuthaza izinto ukuba ziqhekeke ngaphakathi. Kwizinto ezinesakhiwo "se-ghost wire", kukunciphisa ubunzima, amandla, ubude emva kokuqhekeka kunye nokunciphisa indawo, ngakumbi ukunciphisa ubunzima bempembelelo, okuya kukhokelela ekubeni izinto zibe buthathaka kubanda, ngoko ke umxholo we-phosphorus kunye neempawu zesakhiwo sentsimbi Zinolwalamano olusondeleyo kakhulu.
Ukufunyanwa kweMetallographic Kwizicubu "zomgca weghost" embindini wentsimi yombono, kukho inani elikhulu leesulfide ezinde ezingwevu ezikhanyayo. Izinto ezingezizo zesinyithi kwintsimbi yesakhiwo zikhona ikakhulu ngohlobo lwee-oxides kunye neesulfide. Ngokutsho kwe-GB/T10561-2005 "Itshati yoHlelo oluQhelekileyo lweMicroscopic Indlela yoVavanyo loMxholo weZinto ezingezizo zesinyithi kwiNtsimbi", izinto ezifakwe kwiType B ziyavulcanized ngeli xesha. Inqanaba lezinto lifikelela kwi-2.5 nangaphezulu. Njengoko sonke sisazi, izinto ezifakwe kwisinyithi ezingezizo zesinyithi ziyimithombo enokubakho yeentanda. Ukubakho kwazo kuya konakalisa kakhulu ukuqhubeka kunye nokuqina kwesakhiwo sentsimbi, kwaye kunciphise kakhulu amandla entsimbi ephakathi. Kucingelwa ukuba ubukho be-sulfide kwi "mgca weghost" wesakhiwo sangaphakathi sentsimbi yeyona ndawo inokwenzeka yokuqhekeka. Ke ngoko, iintanda ezibandayo kunye nonyango lobushushu olucima iintanda kwiindawo ezininzi zemveliso ye-fastener zibangelwa linani elikhulu leesulfide ezingwevu ezikhanyayo ezithambileyo. Ukubonakala kwezi ntambo zimbi kangaka kutshabalalisa ukuqhubeka kweempawu zesinyithi kwaye kwandisa umngcipheko wonyango lobushushu. "Intambo yesiporho" ayinakususwa ngokuyilungisa, njl.njl., kwaye izinto ezingcolileyo kufuneka zilawulwe ngokungqongqo ukususela kwinkqubo yokunyibilikisa okanye ngaphambi kokuba izinto eziluhlaza zingene kumzi-mveliso.
Izinto ezingezizo zesinyithi zahlulwe zaba yi-alumina (uhlobo A) silicate (uhlobo C) kunye ne-spherical oxide (uhlobo D) ngokwendlela ezibunjwe ngayo kunye nokuguquguquka kwazo. Ubukho bazo bunqanda ukuqhubeka kwesinyithi, kwaye imingxunya okanye iimfanta zenziwa emva kokuxobuka. Kulula kakhulu ukwenza umthombo weemfanta ngexesha lokukhuhla kubanda kwaye kubangele uxinzelelo ngexesha lonyango lobushushu, okubangela ukuqhekeka okucimayo. Ke ngoko, izinto ezingezizo zesinyithi kufuneka zilawulwe ngokungqongqo. Imigangatho yentsimbi yangoku ye-GB/T700-2006 "Carbon Structural Steel" kunye ne-GB/T699-2016 "High-quality Carbon Structural Steel" ayicacisi iimfuno zezinto ezingezizo zesinyithi. Kwiindawo ezibalulekileyo, imigca erhabaxa necolekileyo ye-A, B, kunye ne-C ngokubanzi ayidluli kwi-1.5, kwaye imigca erhabaxa necolekileyo ye-D kunye ne-D ayidluli kwi-2.
Ixesha lokuthumela: Okthobha-21-2021
