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NGHIEN CLfU - TRAO DOI / T | U-U HOA THANH PHAN NtN TAO Xi THU6C HAN THIEU KiT HE BAZO THAP OPTIMIZATION OF WELDING SLAG INGREDIENTS OF THE AGGLOMERATED NEUTRAL FLUX FOR SUBMERGED ARC WELDING TS.VuHuyLto TrUdng Dai hpc Bach Khoa Ha Ndi Nghien cttu, sdn xudt thuoc hdn thieu ket he bazd thdp (Aluminate - Rutile - Basic) bing nguyen vit lieu nttdc de han ttt dgng dudi ldp thuoc, cdc hit cdu thep cacbon thdp vd thep hgp kim thdp la vdn de cdp thiet sdn xudt vit lieu hin hiln d nUdc ta Bdi bio niy trinh biy tdm tat kit qud nghien cttu dnh hudng ciia cic ehdt tao xi me lieu thuoc hin den tinh cdng nghe hdn va cdch xdc dinh hdm Ittdng toi Uucua chung, cho me lieu thuoc hdn thieu kit bazd thdp tddng dUdng logi F7A (P)2 theo tieu chudn AWS A5.17-80 Ta khda: Toi Uu hda; Thuoc hin thieu ket he baza thdp; Thuoc hdn F7A(P)2; Tinh cdng nghe hin; Hin tU dgng dUdi ldp thuoc ABSTRACT In this study, the research on mamcfacturing the agglomerated neutral flux (Aluminate - Rutik - Basic) using domestic raw materials for submerged arc welding (SAW) for the production of low-carbon steel and low-alloy steel is currently an urgent inssue manufacturing welding materials This paper presents the results of study the influence of the flux ingredients on welding-technological characteristics and were determined optimized contens of the mixtures of the agglomerated neutral flux F7A(P)2 according toAWSA5.17-80 Keywords: Optimization; Agglomerated neutral flux; Flux P7A(P)2; Welding-technological characteristics; Submerged arc welding (SAW) ISSN 0866-7056 TAP CHl CO KHl VIET NAM, Sd nam 2016 www.cokhivietnam.vn NGHIEN CCrU - T R A O D O I + Lua chpn nen tao xi va ty 1^ cac chSt tao xi chd y^u dam bao chi so bazcJ y^u cSu l.DATVANDE Ngay nay, cong nghe han tU dpng dddi ldp diuoc (Submerged Arc Welding SAW) dddc sd dung nhieu linh vdc nhd: Che tao ket cau thep, dau khi, giao thong, ddng tau, d^' che tao cac ket cau cd kich thddc ldn vdi dUdng han dai va chieu day ldn Vat lieu han dung cong nghe han tu dong diidi ldp thuoc, gom cd day han va thude han Thuoc han phai nhap vdi gia cao va nguyen lieu de san xuat thuoc han d Viet Nam r^t nhieu, nen viec nghien cdu san xuat thuoc han thieu ket he bazd th^p, loai thuoc han cd thi phan ldn la rat can thiet va cd y nghia thUc ti6n cao Trong sd dd nghien cdu thuoc han thieu ket, npi dung so va quan nhat la chpn dupc he tao xi han hpp ly va nghien cdu dUdc ty le cac chat tao xi han phan me lieu thuoc han Loai thuoc han dUdc chpn nghien cdu la diuoc han thieu ket bazd thap tUdng dUdng loai F7A{P)2 theo tieu chuan AWS A5.17 Day la loai thuoc han cd chi s6 bazd B=l,l, vdi ham liidng hidro thap [1,5] Nen tao xi han cua thuoc han, anh hiidng quyet dinh den cac dac tinh cong nghe han cua thuoc han Dac tinh cong nghe han cua thuoc han gdm cac chi tieu chu yeu sau day: Kha nang gay ho quang han va tinh on dinh cua ho quang han; Su hinh va tao dang mdi ban; Tinh bong xi han va chat lUdng be mat moi han; Mdc dp khuyet tat han Bai bao nay, se tap trung nghien cdu anh hudng cua cac chat tao xi chd yeu phan me lieu thuoc han den tinh cong nghe han Ngi dung nghien cdu se giai quyet cac van de sau day: + Nghien cdu anh hUdng cua cac cMl tao xi chu yeu nen tao xi han den tinh c6ng nghe han cua thuoc han + Xac dinh ham Iddng cac chat tao x me lieu thuoc han thieu ket bazd thSp theo cac chi tieu cong nghe han yen cSu DOI Tl/ONG, V A T LIEU VA PHlTONG P H A P NGHIEN c t f u 2.1 B6i tddng nghien cdu Nghien cdu cac ch^t tao xi han cho thuoi han thieu ket he bazd thap tddng dUdng vdi loa thuoc han F7A(P)2, theo tieu chuan cua Hi^j hpi Han My AWS A5.17-80, dildc ki hieu 1: F7A(P)2-BK, cd cac chi tieu ve tinh cong nght han va chi sd bazd nhil sau: - Chi so bazd B = 1.1, xi han thuoc nhon Aluminate - Rutile - Basic theo phan loai cu Vien Han Quoc te (IIW) [ 1,4,5] - Cac chi tieu ve tinh cong nghe hai tUdng dndng vdi loai thuoc han S-727 cua Con ty Han Hyundai (Han Quoc) hoac thude han 01 Flux 10.80 theo cua hang thiet bi va vat lieu ESAB (Thuy Dien) - Day han dung ket hpp vdi thuoc han loai EL8 theo tieu chuan AWS A5.17-80 2.2 Vat lieu va thiet bi nghien cdu - Nguyen lieu dung d^ ch^ tao thuoc chu yeu la nguon nguyen li^u nUdc ISSN 0866 - 7056 TAP CHi CO KHI VI$T NAM, S6 nam 2016 www.cokhivietnam.vn NGHIEN GU'U-TRAO DOI - Vat lieu che tao mau han la thep ket can han SM400B theo JIS G3106 Kich thiidc mdu: 350x200x20 thed tieu chuan ANSI/AWS B4.0 vay, he so se khong xet d day, chi tieu ve tinh bong xi diidc danh gia dinh lupng theo y&u cau toi thieu va dUa vao theo trpng so tieu chi he so chat lUdng be mat mdi han, cd - Thi^t bi nghien cdu chu yeu: xet den cac loai khuyet tat han tren be mat radi Sd dung may ban tU dpng dUdi ldp thuoc cua hang Dosun [2] ban va mdc dp cac khuyet tat dddc danh gia theo tieu chuan TCVN 7472-2005 (tUdng diidng ISO 5817) va dndc Iddng hda theo mdc dp quan 2.3 Phddng phap nghien cdu trpng ddi vdi ngoai dang mdi han Trong trUdng PhUdng phap nghien cdu k^t hpp nghien cdu ly thuyet va thUc nghiem hdp nay, cac quan he cd the md ta nhU sau: Y = f((CaO+MgO), Aip^, CaF^, TiO^) - n g dung quy hoach thUc nghiem de xay dung cac quan he dinh liidng anh hUdng cda cac chat tao xi me lieu thuoc han den cac chi deu tinh cong nghe han - Mo hinh nghien cdu cd dang tong quat: (1) Trong do: Y - la L^ , b, c, h, Bm De xay dUng cac phiidng trinh thUc nghiem (1) can lUa chpn md hinh va xac dinh cac he sd cua phUdng trinh hoi quy Y=f(X.),i=l^k - Giai bai toan toi Uu hda xac dinh ham Trong dd: lUdng toi Uu cda cac chat tao xi thuoc han + X - Cac bien dau vao la ham lUdng cac chat tao xi thuoc ban, gdm: (CaO+MgO), Aip^, CaF^,Ti03 Chieu dai ho quang tdi han dUdc xac dinh theo sd [5] diidi day: + Y - Ham muc tieu la cac chi tieu dac tinh cdng nghe han xem hinh b Hinh Cdc kich thUdc cua moi hdn Theo [2,6] va cac ket qua thi nghiem tham va sang Ipc, cho thay he so hinh dang mdi han dUpc danh gia gian tiep theo cac gia tri b va c nen he so tUdng thich khdng cao Do Hmh So do thieu ddi ho quang tdi hgn Cong lam bong xi han dUpc xac dinh theo mau co kich thUdc nhU sau [5] ISSN 0866 - 7056 TAP CHI CO KHI VIET NAM, Sd nam 2016 www.cokhivietnam.vn ^ NGHIEN CLfU - TRAO D I Theo [1,4,5] va thi nghiem tham dd sani loc da chpn ddpc ndn tap xi dddi day: (CaO + MgO) - A1,0, - CaFj - TiO, Ty le cac nhdm cSu dl ddpc chpn nhd san 1+ + + (CaO-tMgO): 25% AljOj: 30% CaF^: 15% TiOj: 30% 3.3 Xay ddng ke ho?ch thdc nghiem Hinh Kich thUdc vi mau thi tinh hongxi De nghien cdu md hinh phan tinh chat vdi cac dieu kien rang bupc dac trdng KE HOACH THU'C NGHlfiM ZZ = 100% hpac ZX = 3.1 Lda chon dang phddng trinh hdi quy Theo cac tai lieu tham khao, cac md hinh tren cd dang da thdc bac [2,6, nhd sau: Y,=b„+f^bj,+j;^bX+'tKx.x, ,=1 !=i (2) Trong dd: Z_ - Cac bien sd thdc, % X - Cac bien sd ma hda Kd hoach thdc nghiem ddpc chpn la hoach thdc nghiem Max Lean-Anderson [2,3,6 vung nghien cdu la da dien ban chd '.;=: I'J < a < X < b, < Trong dd: - X^ va X la gia tri cua cac bien dau vao; - Y^ - Cac ham muc tieu, gdm cd; Y|=Lj - Chieu dai hd quang tdi han, mm; Yj= b - Chieu rdng mdi han, mm; Y^= c - Chieu cao dap cua mdi han, mm; Y_|=h - Chieu sau ngau cua mdi han h, mm; Yj= B_^ - Chat Idpng be mat mdi han Sd tuong thich cua cac phuong trhih h quy ddpc kiem tra theo chuan sd Fisher va he; tdpng quan Bing Khoing biln thiln cua cdcyeu Bien thdc, % A1,0, CaF, TiO Cac bien s6 CaO, MgO Z, Z, Z, Mdc diidi Mdc tren 3.2 Lda chpn nen tao xi Viec chpn nen tao xi dda tren cac tieu chi cP ban ve chi so bazp, cac chi tieu ly tinh nhd nhiet dp ndng chay, dp nhdt, sdc cang be mat, gdc tham ddt, khdi lupng rieng, va cd xet den ngudn nguyen lieu san cd nddc 16 26 17 27 15 20 30 Tdng cac chat cdn lai: Z^ = 22% gifl cd dii Vdi day ban dddng kinh d=4,0mm di che dp han nhd sau ISSN 0866 - 7056 TAP CHi CO KHf VIET NAM, Sd nam 2016 www.cokhivietnam.vn NGHIEN CO'U-TRAODOI Bang Cdc thdng so che hdn SAW Gia tri cac thdng sd che han Cddng dong di^n h i n I^, A Dien ap han 'u,.v Van tdc han V^, cm/ph Tam vdi dien cdc, m m Gdc nghieng dien tctic 650 28 45 30 Bang Bdng ki hoach thUc nghiem vd kit qud thi nghiem: Gia tri cac bien so TT 10 11 12 13 14 15 16 17 18 19 20 21 CaO, MgO Gia tri cac bi^n sd AIjO, CaFj TIO, X, X 0.26 0.16 0.26 0.16 0.26 0.16 0.16 0.16 0.16 0.26 0.26 0.26 0.226 0.193 0.193 0.17 0.27 0.27 0.17 0.17 0.27 0.27 0.203 0.236 0.17 0.236 0.203 0.17 0.17 0.27 0.27 0.203 0.236 0.22 0.22 0.22 X, 0.05 0.05 0.05 0.15 0.15 0.15 0.116 0.15 0.083 0.083 0.05 0.116 0.15 0.116 0.05 0.083 0.05 0.15 0.1 0.1 0.1 0.3 0.3 0.2 0.3 0.2 0.2 0.233 0.266 0.3 0.266 0.233 0.2 0.233 0.3 0.266 0.2 0.3 0.2 0.25 0.25 0.25 0.226 0.226 0.193 0.21 0.21 0.21 X, Cac ch9t conl^ X, 0.22 0.22 0.22 0.22 0.22 0.22 0.22 0.22 0.22 0.22 0.22 0.22 0.22 0.22 022 0.22 0.22 0.22 0.22 0.22 0.22 b, mm c, mm h, mm Bm Y, Yj Yj 17.8 18.1 16.6 17.5 17.3 17.1 17.5 18.1 18.3 17.4 16.2 17 16.9 16.7 18.2 16.7 18.5 17.2 166 163 16.9 Y3 3.1 3.7 3.9 3.95 3.9 3.7 3.85 3.7 3.8 3.9 3.9 3.8 3.7 3.7 3.4 3.9 4.1 3.8 4.4 Y, 16.75 16.5 16.75 16.25 15.5 15.75 16.75 15.3 16.25 16.75 1615 17 16 15.75 1625 16.2 165 14.25 1475 15.6 15.05 2.5 2.2 2.7 2.8 2.9 2.6 2.3 21 2.7 3.3 2.8 3.1 3.2 21 2.7 2.7 3.1 3.2 2.9 7.5 6.5 6.5 7.6 7.3 8.5 8.3 5.5 6.5 7.6 7.5 7.2 8.1 6.8 7.6 7.2 7.3 mm Tong cac chat cdn lai dUpc gifl co dinh gpi la: Z^ = 22% Cac k^t qua thflc nghiem cua cac chi tieu sau xd ly loai bd nhflng sd lieu chda sai sd thd, a tri trung binh cua cac thi nghiem dflpc dan bang tren ^ ISSN 0866 - 7056 TAP CHI CO KHI VIET NAM, S6 nam 2016 www.cokhivietnam.vn NGHIEN CLfU - TRAO B I KET QUA VA THAO LUAN 4.1 Xay ddng phddng trinh hdi quy Sau xd ly cac sd lieu nhan dddc cac phddng trinh hdi quy nhd sau: L =15 26 + 0,081X - 0.035X, - 0,295X, + 0,081X^ + 0,245X,^ + 0,203X,^ -1- 0,019X/ + 0,109X^; 0,239X,X, - 0,105X^X3 - 0,158X,X - 0,034X^X, - 0,143X,X, + 0,103X,X, Hd sd tdong quan: R' = 0,637 b = 16 94 - 0,207X + 0,015X, - 0,146X, + 0,219X, -1- 0,091X/ -f 0,018X/ -1- 0,I31X/ -1- 0,039X/ 0,119X,X, + 0,034XX - 0,062X,X, - 0,049X^X3 -1- 0,048X,X, - 0,177X,X, He sd tdong quan R' = 0,619 c = 3.99 + 0,065X, - 0,047X, -1- 0,092X3 - 0,05X, - 0,032X,' - 0,0267X,' - 0,053X3' - 0,033X,^ 0,021X,X, - 0,031X^X3 + 0,047X,X, + 0,038X^X3 -1- 0,015X,X, + 0,035X3X He sd tdong quan R' = 0.591 h = 2,87 + 0,123Xj - 0,037Xj -r 0,107X3 - 0,113X^ - 0,036Xj' - 0,007X/ - 0,07X3' - 0,024X/ + 0,042X,> - 0,031X,X3 + 0,036X,X, - 0,007X^X3 - 0,021XjX, -^ 0,088X3X, He sd tdong quan R' = 0,550 B = 7,68 - 0,323X, -f 0,178X, - 0,336X3 -^ 0,25X - 0,13X,' - 0,158X/ - 0,111X3' - 0,094X/ 0,"l94XjX, - 0,069X,X3 + 0,076X,X + 0,051X^X3 + 0,095X,X + 0,101X3X, He sd tdang quan R' = 0,750 4.2 Cac dddng dac trdng Td cac phuong trinh hdi quy bieu dien cac dudng dac tinh cho ham muc tieu quan trpi nhat la chi& dai hd quang tdi han va chat Idpng be mat mdi han dang 2D va 3D nhd sau - Chieu dai hd quang tdi han L|_ phu thude vao ham Idpng cac chat tao xi thude h vdi cac chat cdn lai ddpc lay d mdc co sd nhd sau: Hmh Suphu thugc L^ vio (CaO + MgO) ISSN 0866-7056 TAP CHi CO KHl VI6T NAM, Sd nam 2016 www.cokhivietnam.vn Hinh SUphu thugc i „ vio Alfl, NGHIEN CLfU-TRAOD6| Hmh Suphu thuoc L vdo CaF^ Hinh Suphu thude L^ vdo TiO^ Hinh Suphu thuoc L vao hdm lUdng (CaO + -MgOJ, Aip^ CaF^ vdi Ti0^^25% Hinh Suphu thude L vdo hdm lUdng (CaO + MgO), Aip^ TiO^ vdi CaF^^lO% Hinh 10 suphu thugc L^vdo hdm lUdngAlp^ CaF^ TiO^vdi (CaO + MgO)=21% - Chat Ifldng b^ mat moi han B^ phu thuoc vao ham Ifldng cac chat tao xi thuoc ban vdi cac chat cdn lai dflpc lay d mdc cd sd nhU sau: ISSN 0866 - 7056 TA.P CHf CO KHi VIET NAM, S6 nam 2016 www.cokhivietnam.vn NGHIEN CLfU - TRAO PQl KET QUA VA THAO L U A N 4.1 Xay ddng phddng trinh hdi quy Sau xfl ly cac sd litu nhan dddc cac phddng trinh hdi quy nhd sau: L =15 26 -t 0,081X - 0,035X, - 0,295X3 -1- 0,081X, -1- 0,245X,' + 0,203X/ + 0,019X3' + 0,109X.' 0!239X',X, - 0,105X,X3 - 0,158X,X, - 0,034X^X3 - 0,143X,X, -^ 0,103X3X, f3, He sd tddng quan: R' = 0,637 b = 16,94 - 0,207X, + 0,015X, - 0,146X3 + 0,219X, + 0,091X,' + 0,018X,' + 0,131X3' + 0,039X,' 0,119X3X3 + 0,034X^X3 - 0,062X,X - 0,049X^X3 + 0,048X,X, - 0,177X3X, He sd tuong quan R' = 0,619 c = 3,99 + 0,065X, ^ 0,047X, + 0,092X3 - 0,05X, - 0,032X,' - 0,0267X/ - 0,053X3' - 0,033X/ 0,021X,Xj - 0,031X,X3 + 0,047X,X, + 0,03iX^X, + 0,015X3X, + 0,OXX^X, He sd tdong quan R' = 0,591 h = 2,87 -I- 0,123X3 - 0,037X, -h 0,107X3 - 0,113X^ - 0,036X,' - 0,007X3' - 0,07X3' - 0,024X/ + 0,042X,X - 0,031X3X3 + 0,036X,X, - 0,007X^X3 - 0,021X3X^ -1- 0,088X3X, He sd tUdng quan R' = 0,550 B = 7,68 - 0,323X3 + 0,178X, - 0,336X3 -t- 0,25X, - 0,13X,' - 0,158X3' - 0,111X3' - 0,094X/ 0,194X3X3 - 0,069X3X3 + 0,076X,X, -1- 0,051X3X3 -t 0,095X,Xj + 0,101X3X, He sd tdong quan R' = 0,750 4.2 Cac dtidng dac trting Td cac phuong trinh hdi quy bieu didn cac dddng dac tinh cho ham muc tieu quan trpr nhat la chilu dai hd quang tdi ban va chat Iddng be mat mdi han dang 2D va 3D nhu sau - Chieu dai hd quang tdi ban L^ phu thuoc vao ham lupng cac chat tao xi thude h; vdi cac chat cdn lai ddpc lay d mdc ca sd nhd sau: Hinh Suphu thugc L^^ vdo (CaO + MgO) ISSN 0866 - 7056 TAP CHl CO KHl VIET NAM, Sd nam 2016 www.cokhivietnam.vn Hinh SUphu thugc L^ vio Alp, NGHIEN CLfU - TRAO l Hinh Suphu thugc L^ vdo Cap^ Hinh Suphu thugc L vio TiO^ Hinh Suphu thugc L, vao hdm lUdng (CaO -t MgO), Alp, CaP^ vdi TiO =25% Hinh 10 Suphu thude L,^ vdo hdm lugng Alp, Hinh Suphu thugc L vdo hdm lUdng (CaO + MgO), Alp^ TiO^ vdi Cap =10% CaF^ TiO^ vdi (CaO + MgO)=21% - ChSt Itipng be mat mdi han B^ phu thupc vap ham Idpng cac chat tap xi thude ban vdi cac chat cdn lai ddPc lay d mdc cd sd nhd sau: ISSN 0866-7056 T4P CHl CO KHl VIET NAM, Sd nam 201d www.cokhivietnam.vn NGHISN CLfU - T R A O D O I KET QUA VA THAO LUAN 4.1 X4y ddng phddng trinh hdi quy Sau xfl ly cac sd lieu nhan dflpc cac phUdng trinh hdi quy nhfl sau: L =15 26 + 081X - 0,035X - 0,295X3 + 0,081X, -1- 0,245X,' -^ 0,203X3' + 0,019X3' + 0,109X/ o!239X3X3 - 0,105X3X3 - 0,158X3X - 0,034X3X3 - 0,143X3X^ + 0,103X3X, (3' He sd tupng quan: R' = 0,637 b = 16,94 - 0,207X3 + 0,015X3 - 0,146X3 + 0,219X^ + 0,091X,' + 0,018X3' -1- 0,131X3' + 0,039X,' 0,119X3X3 + 0,034X3X3 - 0,062X,X, - 0,049X3X3 + 0,048X3X, - 0,177X3X, He sd tddng quan R' = 0,619 c = 3,99 -1- 0,065X, - 0,047X3 -h 0,092X3 - 0,05X, - 0,032X,' - 0,0267X3' - 0,053X3' - 0,033X/ 0,021X3X3 - 0,031X3X3 + 0,047X3X, + 0,038X3X3 + 0,015X3X, -1- 0,035X3X, He sd tdPng quan R' = 0,591 h = 2,87 + 0,123X3 - 0,037X3 + "'lO^X, - 0.113X, - 0,036X,' - 0,007X3' - 0,07X3' - 0,024X3' + 0,042X3 - 0,031X3X3 -I- 0,036X3X, - 0,007X3X3 - 0,021X3X, -I- 0,088X3X^ He sd tdPng quan R' = 0,550 B = 7,68 - 0,323X, + 0,178X3 - 0,336X3 + 0,25X, - 0,13X,' - 0,158X3' - 0,111X3' - 0,094X/ 0,194X3X3 - 0,069X3X3 + 0,076X3X3 -t 0,051X3X3 + 0,095X3X^ -I- 0,101X3X, He sd tflong quan R' = 0,750 4.2 Cac dtidng dac trting Tfl cac phdong trinh hdi quy bieu dien cac dudng dac tinh cho ham muc tieu quan trpr nhat la chieu dai hd quang tdi han va chat Iflpng bl mat mdi han dang 2D va 3D nhu sau - Chieu dai hd quang tdi ban L^ phu thupc vap ham Iddng cac chat tap xi trpng thunc hi vdi cac chat cdn lai dflpc lay d mflc cfl sd nhu sau: Hmh Suphu thugc 1,^ vao (CaO -t MgO) ISSN 0866-7056 TAP CHl CO KHl VlfiT NAM, Sd nam 2016 www.coldiivietnam.vn Hmh suphu thugc L^ vao Alp, NGHIEN CO'U-TRAOD6| Htnh Suphu thugc L vdo CaF^ Hinh Suphu thude L^ vdo TiO^ Hmh Suphu thugc L vdo hdm lUdng (CaO + MgO), Alp^ CaF^ vdi TiO =25% Hinh Suphu thugc L vdo hdm lUdng (CaO + MgO), Alp^ TiO^ vdi CaF=10% Hinh 10 suphu thugcL^vdo hdm lUdngAlp^ CaF^ TiO^ vdi (CaO + MgO)=21% - Chat Ifldng b ^ mat moi ban B^ phu thupc vao ham lUcfng cac chat tao xi thuoc ban vdi cac ch£t cdn lai dfldc ISy d mdc cd sd nhd sau: ISSN 0866 - 7056 T^P CHl CO KHl V I £ T NAM, S6 nam 2016 www.cokhlvietnam.vn NGHIEN CLfU - TRAO B Q I m Die (IT lis (« »» "' Hind 11 Sifpliu thugc S„ vao (CuO -f MgO) IS m S3 m in iằ ã< ^i^ ("^

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