Izinto zokusetshenziswa ezisezingeni eliphezulu ziyisisekelo sokukhiqiza izibambo zekhwalithi ephezulu. Kodwa-ke, imikhiqizo eminingi yabakhiqizi bezibambo izoba nemifantu. Kungani lokhu kwenzeka?

Njengamanje, izincazelo ezivamile zezinduku zensimbi zesakhiwo sekhabhoni ezinikezwa yimishini yensimbi yasekhaya yi-φ 5.5- φ 45, ububanzi obuvuthiwe buyi-φ 6.5- φ 30. Kunezingozi eziningi zekhwalithi ezibangelwa ukuhlukaniswa kwe-phosphorus, njengokuhlukaniswa kwe-phosphorus kwenduku yensimbi encane kanye nebha. Ithonya lokuhlukaniswa kwe-phosphorus kanye nokuhlaziywa kokwakheka kwemifantu kwethulwa ngezansi ukuze kubhekwe. Ukwengezwa kwe-phosphorus kumdwebo wesigaba sekhabhoni yensimbi kuzovala ngokufanayo isifunda sesigaba se-austenite futhi kukhulise ngokungenakugwenywa ibanga phakathi kwe-solidus ne-liquidus. Lapho insimbi equkethe i-phosphorus ipholiswa kusukela koketshezi kuya kokuqinile, idinga ukudlula ebangeni lokushisa elikhulu.

Izinga lokusabalala kwe-phosphorus ensimbini lihamba kancane, kanti insimbi encibilikisiwe ene-phosphorus concentration ephezulu (iphuzu eliphansi lokuncibilika) igcwele ama-dendrite okuqala aqinile, okuholela ekuhlukaniseni i-phosphorus. Ngemikhiqizo evame ukuba nemifantu ngesikhathi sokwakheka okubandayo noma ukukhishwa okubandayo, ukuhlolwa nokuhlaziywa kwe-metallographic kukhombisa ukuthi i-ferrite ne-pearlite zisatshalaliswa ngemichilo, futhi kukhona i-ferrite emhlophe enebhande ku-matrix. Kunezindawo zokufakwa kwe-sulfide ezimpunga ezikhanyayo ezijikelezayo ku-matrix ye-ferrite enebhande. Isakhiwo esinebhande se-sulfide sibizwa ngokuthi “umugqa we-ghost” ngenxa yokuhlukanisa i-sulfide.
Isizathu ukuthi indawo enokwehlukaniswa okukhulu kwe-phosphorus iveza indawo emhlophe ekhanyayo endaweni yokucebisa i-phosphorus. Esitsheni sokubumba esiqhubekayo, ngenxa yokuqukethwe okuphezulu kwe-phosphorus endaweni emhlophe, amakristalu ekholomu acebile ngokugxilisa kwe-phosphorus, okunciphisa okuqukethwe kwe-phosphorus. Lapho i-billet iqina, ama-dendrite e-austenite ahlukaniswa kuqala nensimbi encibilikisiwe. I-phosphorus ne-sulfur kula ma-dendrite ayancishiswa, kodwa insimbi encibilikisiwe ekugcineni eqinisiwe iqukethe izakhi ze-phosphorus ne-sulfur. Iqina phakathi kwezingqimba ze-dendrite ngoba izakhi ze-phosphorus ne-sulfur ziphakeme. Ngalesi sikhathi, kwakheka i-sulfide, futhi i-phosphorus iyancibilika ku-matrix. Ngenxa yokuthi izakhi ze-phosphorus ne-sulfur ziphakeme, kwakheka i-sulfide lapha, futhi i-phosphorus iyancibilika ku-matrix. Ngakho-ke, Ngenxa yokuqukethwe okuphezulu kwezakhi ze-phosphorus ne-sulfur, okuqukethwe kwekhabhoni kusisombululo se-phosphorus esiqinile kuphakeme. Kuzo zombili izinhlangothi zebhande le-carbonaceous, okungukuthi, kuzo zombili izinhlangothi zendawo yokucebisa i-phosphorus, kwakhiwa ibhande elide nelincane le-pearlite elihambisana nebhande elimhlophe le-ferrite, futhi izicubu ezivamile eziseduze ziyahlukaniswa. Ngaphansi kwengcindezi yokushisa, i-billet izokwelula iye esiqondisweni sokucubungula phakathi kwemishayo, ngoba ibhande le-ferrite liqukethe i-phosphorus ephezulu, okungukuthi, ukuhlukaniswa kwe-phosphorus kuzoholela ekwakhekeni kwesakhiwo sebhande le-ferrite elikhanyayo elinzima nesakhiwo sebhande le-ferrite elikhanyayo elibanzi. Kungabonakala ukuthi kukhona nemichilo ye-sulfide empunga ekhanyayo ebhandeni le-ferrite elikhanyayo elibanzi, elisakazwa ngomucu omude webhande le-ferrite elicebile nge-sulfide, esivame ukulibiza ngokuthi “umugqa we-ghost”. (Bheka Umfanekiso 1-2)

I-Flange Bolt

Enqubweni yokugoqa eshisayo, inqobo nje uma kukhona ukuhlukaniswa kwe-phosphorus, akunakwenzeka ukuthola isakhiwo esincane esifanayo. Okubaluleke kakhulu, ngoba ukuhlukaniswa kwe-phosphorus kuye kwakha isakhiwo "somugqa we-ghost", kuzonciphisa ngokungenakugwenywa izakhiwo zemishini zento. Ukuhlukaniswa kwe-phosphorus ensimbini eboshiwe nge-carbon kuvamile, kodwa izinga layo lihlukile. Ukuhlukaniswa kwe-phosphorus okukhulu (“umugqa we-ghost”) kuzobangela imiphumela emibi kakhulu ensimbini. Ngokusobala, ukuhlukaniswa okukhulu kwe-phosphorus kuyimbangela yokuqhekeka kwekhanda elibandayo. Ngenxa yokuthi okuqukethwe kwe-phosphorus ezinhlamvini ezahlukene zensimbi kuhlukile, izinto zinamandla nobunzima obuhlukile. Ngakolunye uhlangothi, kwenza izinto zikhiqize ukucindezeleka kwangaphakathi, okuzokwenza izinto zibe lula ukuziqhekeka. Ezintweni ezinesakhiwo "somugqa we-ghost", kungenxa yokwehla kobunzima, amandla, ukunwebeka ngemva kokuphuka nokuncipha kwendawo, ikakhulukazi ukwehla kokuqina komthelela, ukuthi okuqukethwe kwe-phosphorus ezintweni kunobuhlobo obuhle nesakhiwo nezakhiwo zensimbi.
Esicutshini "somugqa wezipoki" esiphakathi nendawo yokubona, inani elikhulu le-sulfide encane, empunga ekhanyayo yatholwa yi-metallography. Ukufakwa okungeyona insimbi ensimbini yesakhiwo ikakhulukazi kukhona ngesimo sama-oxide nama-sulfide. Ngokusho kwe-GB/T10561-2005 Standard Classification Diagram yokuqukethwe kokufakwa okungeyona insimbi ensimbini, okuqukethwe kwe-sulfide kokufakwa kwe-Class B kungu-2.5 noma ngaphezulu. Ukufakwa okungeyona insimbi kungumthombo ongaba khona wokuqhekeka. Ukuba khona kwayo kuzolimaza kakhulu ukuqhubeka kanye nokuqina kwesakhiwo sensimbi, ngaleyo ndlela kunciphisa kakhulu amandla e-intergranular.
Kucatshangwa ukuthi i-sulfide esakhiweni sangaphakathi "umugqa we-ghost" wensimbi yingxenye eqhekeka kalula. Ngakho-ke, inani elikhulu lama-fasteners aqhekeka ekucindezelweni okubandayo kanye nokwelashwa kokushisa endaweni yokukhiqiza, okwabangelwa inani elikhulu lama-sulfide amade ampunga akhanyayo. Le ndwangu engalukiwe yabhubhisa ukuqhubeka kwezakhiwo zensimbi futhi yandisa ingozi yokwelashwa kokushisa. "Umugqa we-ghost" awukwazi ukususwa ngokulungisa kanye nezinye izindlela, futhi izinto ezingcolile kufanele zilawulwe ngokuqinile ngaphambi kokuncibilikisa noma izinto zokusetshenziswa zingene esitshalweni. Ngokusho kokwakheka kanye nokuguquguquka, ukufakwa okungeyona insimbi kuhlukaniswe nge-alumina (uhlobo A) silicate (uhlobo C) kanye ne-spherical oxide (uhlobo D). Ukubukeka kwayo kuzonqamula ukuqhubeka kwensimbi futhi kube yimigodi noma imifantu ngemva kokuxebuka, okulula ukwakha imifantu ngesikhathi sokucindezelwa okubandayo futhi kubangele ukugcwala kokucindezeleka ngesikhathi sokwelashwa kokushisa, ngaleyo ndlela kubangele ukucima imifantu. Ngakho-ke, ukufakwa okungeyona insimbi kufanele kulawulwe ngokuqinile. I-Structural Carbon Structural Steels GB/T700-2006 kanye ne-GB T699-2016 High Quality Carbon Steels yamanje ibeka phambili izidingo zokufakwa okungeyona insimbi. Ezingxenyeni ezibalulekile, ngokuvamile uchungechunge oluqinile lohlobo lwe-A, B, C, uchungechunge oluncane aludluli ku-1.5, D, uhlelo oluqinile lohlobo lwe-D kanye nezinga lesi-2 alidluli kuzinga lesi-2.

I-Hebei Chengyi Engineering Materials Co., Ltd. yinkampani enolwazi lweminyaka engu-21 lokukhiqiza izikhonkwane kanye nokuthengisa. Izikhonkwane zethu zisebenzisa izinto zokusetshenziswa ezisezingeni eliphezulu, ubuchwepheshe bokukhiqiza obuthuthukisiwe kanye nokukhiqiza, kanye nohlelo lokuphatha oluphelele ukuqinisekisa ikhwalithi yomkhiqizo. Uma unesifiso sokuthenga izikhonkwane, sicela usithinte.