EEaBsacSNGNGHl Si-15 or IC' lo NGHIEN cufu ANH Hl/dNG CUA CHE DO CAT DEN DO NHAM BE MAT KHI GIA CONG TREN MAY PHAY CNC INFLUENCES OF CUTTING MODE ON SURFACE ROUGHNESS PROCESSED BY CNC MILLING MACHINE N g u y i n Huy KiSn, Pham Van Ddng, Pham Van Bong, Tran V3n Bich T6m t^t Bai bao trinh bay ket qua nghien cihi anh hifdng cua che cat den nham be mat gia cong tren may phay CNC Ket qua nghien cdu la co sd cho cac nha cdng nghe lUa chon che cat toi inj nham nang cao chat lu'gng be mat, dd cliinh xac va nang suat gia cong gia cdng tren may phay CNC Td khda: Che cat, nham Abstract The article presents influences of cutting mode on surtice roughness when milling by CNC milling machine The research result is the basis for technologists to select optimum cutting mode to raise the surface quality, accuracy and processing capacity ofthe parts when processing by CNC milling machine Keywords: Cutting mode, roughness ThS Nguyen Huy Kien,TS Pham Van {)6ng,TS Pham Van Bong Tnfcmg E)ai hoc Cong nghiep Ha Ngi GS.TS Iran VSn Dich -TriTflng Oai hoc Bach khoa Ha Ndi Email: nguyenhuykienl 981 ggmalLcom I.OATVAND^ Chat lu'dng be mat ehi tiet sau gia cong tr^n may phay CNC phu thupc vao nhieu yeu to, nha: vat lieu gia cong, phirong phap gia cong, dung cu cSt, lue eit, nhiet eat, he thong cong nghe, ehe cat Khi dieu Icien va thiet bj gia eong khong doi, de nang eao nang Hinhl.May phay D00SANDNM400 Ngaynhanbai: 06/01/2014 Ngiy chl[p nhan dang: 20/03/2014 suat, chat li/ong be mat ehi tiet va dp ehinh xac sau gia eong thi viec lUa chon ehe elt la het siic can thiet Cae nghien cu'u da chi moi quan he giCfa nham be mat (R^) vdi che d6 cat (V, S, t) la quan he ham luy thiia [4]: R^^Cp.V^S^f (1) Trong do: C la hang so; a, b, e la cae Hinh May dd nham Mitutoyo SJ - 400 Tap dii KHOA HOC & CONG NGHE S o 2 so mu Hang s6 C va eac so mu a, b, c difOe xac dinh b i n g thiie nghi&m.Doi vdi dieu kien gia cong ehi tiet cu the thi viee xae djnh eac gia tri C , a, b, c se giup nha eong nghe tinh toan, lUa chon duoc che c i t hdp ly theo yeu eau ve chinh xac gia cong 2.THU'CNGHI|M 2.1 Vat lieu va thiet bj thu'c nghiem 2.1.1 Mdy gia cdng vd dung at ck - May gia eong: SCf dung may phay CNC nhan hieu DOOSAN DNM4O0 (hlnh 1) Han Qu6c san xuat - Dung cu elt: Dao phay ng6n, s6 rang Z = 2, dudng kinh D = 26 mm, lUdi c i t g i n manh hop kim eufng nhom cae bit ky hieu 490R-08T308-PM cua hang Sandvik (Thuy Dien) 2.T.2 Vgt lieu gia cong vd che tudi ngudi - Vat lieu gia eong la thep 40Cr, thep hoa tot, dUdc sCf dung rdng rai che tao may Kich thifdc mau thi nghiem: 50x30x25 mm - Lam mat: Diling dung dieh Emunxy 4%, luu lUdng 20 lit/phut 2.7.3 Thiit bj do nhdm - May dp nham Mitutoyo SJ - 40C (hinh 2) - Thong so do: ehi tieu danh giS i{ nham R^ theo tieu ehuan ISO; chi^uda chuan: 0,8 mm, tren ichocing; lo? dau do: kim cUdng (R = mm) tjfl xuc; ap luc do: 0,75 N; toe dp: 0,05mif| 2.2 Phuong phap thUc nghiSm SClENCETECHNQLOGYl Nghien eijfu dupe thuc hien tren 11 mau, vat lieu 40Cr Sau eac mau dUdc xac dinh mac thep bang phUdng phap quang pho, tien hanh phay tho, phay ban tinh, kiem tra eae th6ng so hinh hoe va phay tinh; sCrdung phUdng phip quy hoach thuc nghiem, ehpn dang phuong trinh h6i quy, xac djnh th6ng so thi nghiem va tien hanh thuc nghiem Do, kiem tra danh gia nham; xay dUng cong thu'c xae djnh moi quan he giufa cae thong so ehe eat vdi 66 nham be mat chi tiet sau gia cong 2.3 Ca sd danh g\A s6 lieu thuc nghiem 2.3.1 Chgn dgngphuang trinh hoi quy Di nghien cu'u moi quan he giO'a eae thong so ch^ dp elt vdi dp nham be mat ehi tiet sau gia edng, tae gia stf dung phUdng phap binh phUdng nh6 nhat (BPNN) vdi bien so k va dang ham hoi quy thUe nghiem: y = au-Ha,x, +a^Xj-f + ^^\ (2) 2.3.2 S6 thi nghiim va thong so thi nghiem • So t h i nghiem: - Mdi quan he giQa eae t h o n g sd dupc m d t l theo sd d o (hinh 3): ^ X, V Bang Thong so che dp cat thu'c nghiem vantocdt V(m/pli) 163 212 261 Thong so Gia tn Gi^tri trung binh Gia tn max Tocflocat Bode tien dao Chieu S3U cat n (v/ph) S (mm/ph) (mm) 2000 400 600 800 0,1 0,2 0,3 260O 3200 Bang Ket qua thuc nghiem Bien ma hoa TT 10 11 Thong so rang nghe Toe cat X, +1 +1 +1 +1 0 X2 -1 -1 +1 +1 -1 -1 +1 +1 0 X, -1 -1 -1 -1 +1 +1 +1 +1 0 n (m/ph) (v/ph) 163 261 163 261 163 261 163 261 212 212 212 2000 3200 2000 3200 2000 3200 2000 3200 2600 2600 2600 ^: Bien ngau nhien - Sd thi nghiem dUdc xac dinh [3] theo cdng thu'c: N = 2'' = Vdi bien dau vao k = ta cd sd thi nghiem chinh N = 8, de nang eao ehinh xac tac gia them thi nghiem tam.Tong sd thi nghiem N = -i- = 11 • Thong so thi nghidm: Can cijf vao thdng sd ky thuat cCia may, pham vi cho phep stf dung cua dung cu elt eua nha san xuat eae thong sd ehe elt diXOe ehpn vung sau: -h Van tde elt V: 163 -261m/ph (n = 2000-3200 v/ph) -I- BUdc tien S: 400 - 800 mm/ph Hlnh Sddo moi quan he giOa thong so dau vao + Chieu sau elt t: 0,1 - 0,3mm ^a dau Thdng sd eh^ dp elt thuc nghiem + Cac bi^n dau vao x, dieu khien the hien b i n g Sugc: Mdi quan he gifla dp nham va che x,:Van tdc e l t V (m/ph) elt the hien qua edng thtifc (1), dd la: x^: Budc tien dao S (mm/ph) R^ = C^.\J\S\t' Xj: Chieu sau e l t t (mm) Logarit cdsdephUcJng trinh (Dta duoe: + Bien d a u bj dieu khien: ln(R; = In(Cp) -1- a.ln(V) + b.ln(S) + y: e p n h a m be mat R, (nm) c.ln(t) (3) + Bien k h d n g dieu khien dUpe: X, Budc tien S V (mm/ph) 400 400 800 800 400 400 800 800 600 600 600 Chieu sau c3tt (mm) 0,1 0,1 0,1 0,1 0,3 0,3 0,3 0,3 0,2 0,2 0,2 Do nham theoR (pm) 0,45 0,53 1,38 0,88 0,42 0,29 1,24 0,57 0,55 0,59 0,60 Cat y = ln(RJ; a^, = In(C^); a, = a; a^ = b; 83 - c; X, - ln(V); x^ = ln(S); Xj = ln(t) Ta dupe: y = a^ + a,x, -t- a^x^ -1- a^x^ Mu'c tren la x/"taed;x"' = l n x ^ j Mufc dudi lax"":x"" = lnx^|^; Mufc cdsd lax,™: ^W = - ( l n x , „ Khoing bien thien la p^ ta ed: p, =-(lnx,^^,-lnx„„,n) 2.4 Ket qud thUc nghiem Chuyen eae bien tCf t u nhien sang eae bien ma hda khdng thLf nguyen Vdi thue nghiem bien dau vao thay doi, tien hanh lam thi nghiem tai cac dinh ddn hlnh deu va thi nghiem d tam; sau gia eong xong cae mau, tien hanh dp nham tren may dp nham Mitutoyo SJ - 400 Ket qua thuc nghiem (bing 2) 2.4.1 Quy hoach so liiu thi/cnghiem Theo phUdng phap BPNN ta cd ham hoi quy thuc nghiem tdng quat: y = ag + a^ x, -i-a^Xj-i- " + a^,X|^ Xac djnh a,^ a,, a, a cho S dat So 22.2014-TapchiKHOAHOC&CONGNGHl laihyjihWCONG NGHE Bang B Ket qua tinh logarit cac thong so thi nghiem ln(S) ill(t) InR, Xj Xj M 5.99146 -2.30259 -0.79851 5.56452 5.99146 -2.30259 -0.634IU 1.38 5.09375 6.68461 -2.30259 0.3220B 0.1 88 5.56452 6.68461 -2.30259 -0.12713 400 0.3 0.42 5.09375 5.99146 -1.20397 -0.86750 400 0.3 0.29 5.56452 5.99146 -1.20397 -1.23717 163 800 03 124 5.09375 6.68461 -1.20397 0.21511 261 800 0.3 0.57 56452 68461 -1.20397 -0.56212 in(V) VantdcV Budc Chieu sau cat t Bd nham theo (m/ph) tien S (mm/ph) (mm) ».(pm) I 163 400 0.1 0.45 5.09375 261 400 01 0.53 163 800 0.1 261 800 163 261 TT 212 600 0.2 0.55 5.35659 6.39693 -1.60944 -0.59714 10 212 600 0.2 0.59 35659 6.39693 -1.60944 -0.52763 11 212 600 0.2 0.60 5.35659 6.39693 -1.60944 -0.51083 gia tri nhd nhat: Cae gia tn a^^, a,, a^ a^ la eae he sd tuong u'ng cCia ma tran [A]: [A]= M= 5.09375 5.99146 -2.30259" 5.56452 5.99146 -2.30259 5.09375 6.68461 -2.30259 5.56452 6.68461 -2.30259 5.09375 5.99146 -1.20397 5.56452 5.99146 -1.20397 5.09375 6.68461 -1.20397 6.68461 -1.20397 5.35659 6.39693 -1.60944 5.35659 6.39693 -1.60944 5.35659 6.39693 -1.60944 5.56452 Vdi: [X] [A] = [Y] (5) + Ma tran thdng sd dau vao [X] la logarit cd sd e eae gia trj V, S, t diing thi nghiem + Ma tr§n thdng sd dau [Y] cd cac he sd la logarit eo sd e eae gia trj 66 nham dupe tren eae mau thf nghiem Nhan hai ve cua (5) vdi ma tran chuyen vi X^ cua ma tran X: [xr.[x].[A]-txr.[Y] eat [M] = [X]^ [X] ta cd: [M] [A] = [XV.m Gil si:rdet(M) ^^ thi [M] la ma tran khci nghieh.Tacd; [A]-[MI-'.[X]\[Y] (6) Logarit ca sd e eae gia tn V, S, t va R^ ta dUdc ket qua b i n g TCf bing va phuang trinh hoi quy thue nghiem (2) ta cd: I TapdiiKHOAHOC&CONGNGHE S o 2 SCf dung phan mem Excel tinh toan ta daoc ma tran [A]: ^-0.7985ll -0.63488 0.32208 -0.12783 -0.86750 Vdi [Y]= -1.23787 -»[A]= 0.21511 -0.56212 "-4.52911' a^ -0.77396 a, 1.20887 a -0.28811 Sj -0.59784 -0.52763 -0.51083 Cac he so cua phi/ong trinh h6i quy thuc nghiem: a, = -4,52911-.C =e-'."'" =0,01079 a =-0,77396; a-= 1,20887; SClENCETECHNOLOGYl BSng Ket qua tinh to^n So tin cay TT Xl X; Xi y 5.09375 5.99146 -2.30259 -0.799 5.S6452 5.99146 -2 30259 5.09375 6.68461 -2.30259 5.56452 6.68461 5.09375 Y y.-y: (y-y )' (y-y;)' 0.56517 •0.23334 0.098697 0.054447 •0.635 0.92953 0.29465 0.403070 0.086817 0322 0.27276 0.04933 0.650330 0.002433 -2.30259 -0.128 0.09160 -0.03623 0.127102 0.001313 99146 -1.20397 -0.868 0.88169 0.01419 0.146807 0.000201 5.56452 5.99146 -1.20397 •1.238 1.24605 0.00817 0.567804 0.000067 5.09375 6.68461 -1.20397 0.215 0.04377 0.25888 0.489242 0.067018 5.56452 6.68461 -1.20397 -0562 0.40812 -0.15400 0.006049 0.023714 5.35659 6.39693 -1.60944 -0.598 0.47814 -011970 012880 0.014327 10 5.35659 6.39693 -1 60944 •0.528 0.47814 -0.04949 0.001874 0.002449 11 5.35659 6.39693 -1.60944 -0.511 0.47814 -0.03268 0.000701 0.001068 2.50455 0.25386 Totig -5.328 Trung binh y « -0.484 a, = - 0,28811 Ta CO p h u o n g t r i n h h o i q u y t h u c n g h i e m ; y = - , 1 - , 7 X,-1-1,20887 X j O , 8 1 X P h u o n g t r i n h q u a n h e giOa d o n h a m R^ v a cac t h o n g s o che d p c3t: 0.25046-0.02539 - = 0.905 025046 oJ (7) Op tin cay: r = 90,5% • Kiem djnh cac he so a,: R, = 0,01079.V"">»'.S''»".t*"'" (8) 2.4.2 Danh gid tin cay ciia ham hoi quy thttc nghiem Oanh gia tin cay: - Xac dinh phUdng sai dU S^^: 5d.' 5^ (A) N-k-1 (10) £)6 tin cay duoc d^nh gia theo [5] cong thu'c: Trong dd:N la sd thi nghiem (N = 11); oJ Trong do: S'(A) = ([Y]-[X].[A])M[YI-[X].[A]) k la sd thdng sd can xac dinh trU a^; (9) "^-^-Ify.-yi.)" Dung phan mem Excel giai eae bai toan ma tran ta tinh duae: S^(A) = 0,25386 5i o'J = ^ Z ( y , - y , ) ' Vdi; y - la logarit ca sd e gia tri dp nham R^ thUe nghiem 5odUde(y, = lnRJ; y - gia tri trung binh logarit cd sd e dp nham R^ theo :huc nghiem dupc; y ' - l a logarit dp nham R^ theo ham hdi quy thue nghiem; N - s d t h i nghiem SCrdung phan mem Excel ta tinh dupe ket qu5 dp tin cay :he hien b^ng ^l =rr7-It>'i -yi*^' = - ^ - 5 =0.25046 ' N-1 I \\-i CT'^ = — Z ( y i - y ' i ) ' = — ' — *0.25386 = 0.02539 ' N-1 I 11-1 S'(A) 0.25386 N-k-1 11-3-1 - 0.036265813 - > 5^^=0,19043585 - Xac djnh sU tdn tai eCia cac he sd a^: Cac he so a, tdn tai [51 xae dinh theo edng thtfc: W= (11) ptt ,(N-l Trong do: m^^ la so hang thuf ii (dudng cheo chinh) cua ma tran M ' v6i: [(M] = [XF [Xj; ^106.76821 -11.95875 M = -6.53236 0.78803 -11.95875 -6.53236 078803' 2.24794 -0.00804 -0.00782 -0.00804 1.03272 -0.00773 -000782 -0.00773 0.40674 So 2 Tap dii KHOA HOC & CONG NGHt 1S B!Wilil«Wc6NG NGHE ^ Hinii Do till quan lie giifa R^ vdi V va t Hlnli4.e6thiqiianhegiiiaR^v61VvaS Taed: l^""''l~|Sj^7m„|~|0.19O43585.Vl06.7682l| = 1-2.30167| = 2.30167 1 1-1 ^' I I -0.77396 Hinli Do thj quan he giCa R^ vdi S vl t tren may phay DOOSAN DNM400: R^ = 0,01079 V ^ " ' " S ^ ' " " ' t ° - ' " " Ket qua nghien cOfu se giup cho viec tinh toan, lUa chgi ehe dd cat hop ly, nang cao dUde nang su^t, ehit luong^ mat va dd ehinh xac gia edng J I Phan hien khoa lioc: TS Hoang V i n ^ I Sdu V m „ I ~ 10.19043585.V2.247941 = 1-2.710681 = 2.71068 """"' IS^^Vm^jl '|o.19043585.Vl.03272| = 16.246531 = 6.24653 |.;,J 1.20887 Sj,Jn\7] |o.l9043585.V0.40674l |-2.37219| = 2.37219 Theo bang phan bo Student [3] vdi t^^^ (N _^j=l,943 Nhan thay: TAILIEUTHAMKHAO [1] Nguyen Trong Binh, Nguyen Tlie Bat, Tran Van flich, Cong nghi may, I4XB Khoa hoc va Ky thuat, Ha Noi, 2002 |.;»1 = >tt^„g(N-k-U) v ^ i i - - ^ Do dd eae he sd a thuc sU tdn tai, phuong trinh hoi quy thuc nghiem (7) tdn tai, nen tdn tai mdi quan he giCfa dd nham be mat vdi che dp eat nhu sau: R, = 0.01079 V"'"^»* S'-^""" f»''*«" 2.2.3 Do thf quan he gida nhdm vdi ^dng so chi cat Dijng phan mem MatLab ve dd thj bieu dien mdi quan he giCfa dp nham R^ vdi gia tri cua thdng sd che dp cat fid thi mdi quan he giCfa R^ vdi V va S (hlnh 4) Dd thi mdi quan he giCfa R^^ vdi V va t (hinh 5) Do thj mdi quan he giij'a R^ vdi S vat (hinh 6) K^T L U A N Ket q u i nghien ciJu, thUc nghiem va xd ly sd lieu thuc nghiem da xac djnh dupe mdi quan he toan hpc giufa dd nham be mat chi tiet sau gia cdng (RJ vdi cac thdng sd cdng ngh§ ve ehe dp eat (V, S, t) gia cdng chi tiet vat lieu 40Cr ' T a p d i i K H O A HOC&CONG N G H E - S o 2 [2] Pham Van Bong, Luan an tien sT ky thuat, 2007 [3].Tran Van Bich, Cac phifong phap xac dinh chinh xacgia c6ng,l hocva Kythuat, Ha Noi, 2010 [4) Tran Sy Tuy, Nguyen Duy, Trinh Van Tit, Nguyen 1)/ c3t got kim lo^HB Khoa hoc va Ky thuat Ha Noi, 1997 [51 Nguyen Doan % Quy hoadi thifc nghiem, NXB Khoa hoc va Ky t h u ^ ii,2003 [6] P A.Barabasup, Ngucri dich Tran Van Djch, Ky thuat phay, NXB ',, thuat, Ha Noi, 1984 [7] Mike S Lou, Joseph C Chen, Caleb M Li, Surface Roughness technique for CNC End Milling, Joumal of industrial technology, 1999 [8] M Alauddln, M A El Baradie v M S J Hashmi, Optimization of Sllto finish m end milling Inconel, Journal of Materials Processing Technology, 2(KI%j [9] M flKo6coH, TexHOJiomfi CTaHKOCTpoeniw, HsflareiHiW "MauiHHOCTpoeHiie", MocKBa, 1996 [10] A r KocMnoBoii it P K MeuiepoKOBa, CnpaBOHHH TexHOnora MaujHHOCTpoHTenfl, M3flaTenbciBo"MaiiiHHocTpoeHne", MocKBa 2001 ... eac mau dUdc xac dinh mac thep bang phUdng phap quang pho, tien hanh phay tho, phay ban tinh, kiem tra eae th6ng so hinh hoe va phay tinh; sCrdung phUdng phip quy hoach thuc nghiem, ehpn dang phuong... phan mem Excel giai eae bai toan ma tran ta tinh duae: S^(A) = 0,25386 5i o''J = ^ Z ( y , - y , ) '' Vdi; y - la logarit ca sd e gia tri dp nham R^ thUe nghiem 5odUde(y, = lnRJ; y - gia tri trung... Di nghien cu''u moi quan he giO''a eae thong so ch^ dp elt vdi dp nham be mat ehi tiet sau gia edng, tae gia stf dung phUdng phap binh phUdng nh6 nhat (BPNN) vdi bien so k va dang ham hoi quy thUe