Non conventional machining process

Non Traditional Machining Process Advance Manufacturing Process

1. Non Co n v e n tio n al Machining

2. Comparison b e t w een Co n v e n tional and No n - c o n v e n tional machining : S r . No Co n v e n ti o n a l Non-Co n v e n ti o n a l Di r ect c o n t act of t ool and w orkpiece. T ools a r e no n - c o n v e n tional t ec h niq u e l i k e Las e r beam, el e ctric a r c e t c. 1 C u t ting t ool is al wa y s ha r der than w/ p . T ool m a y not be h a r der and it m a y not be p h y s i c al p r es e n c e. 2 3 T ool l i f e is l e ss d u e t o h igh w ea r . T ool l i f e is mo r e. G e ne r a l ly Mac r os c o p ic c h ip f orm a tion. M at e r i a l r e m o v al occ u r w ith or w ithout c h ip f or m a tion . 4 It uses di f f e r e n t ene r gy l i k e el e ctri c al, Ther m o-Chem i c al e t c. t o p r o v i de machining. M a t er i al r em o v al t a k es place du e t o a pp l ic a tion of c u t ting f o r ce. 5 6 S u i t a b le f or all m at er i al Not sui t able f or all m a t er i al. It c a nn ot b e u sed t o ma k e p r o t oty p e p arts v e r y e f f ecti v e l y . It c an b e u sed t o p r o du ce p r o t ot yp e parts v e r y e f f ecti v e l y . 7

3. Electri c al Discha rg e Machining or Spark E r osion or Spark mac h in i ng or Thermal E r osion or Elec t r o E r osion P r ocess

4. control gap Filter Dielectric Tool feed , Tool Spark discharge m • gap Princi p le of E D M: Servo to I

5.  T h e main a t t r ac t ion o f EDM o v er c o n v e n ti o nal m a chining is th a t e r ode un d esi r ed this t e c hni q ue use th e rmoel e c tr i c p r ocess to m a t e r ial f r om the w/p. C o n s tr u ction :  S y s t em c o n si s t o f Sh a ped t o o l, P o w er supp l y s o u r c e , Die l e c t ri c fluid and its ci r cul a tion l i ne, S e r v o c o n t r olled t o o l and w ork. f e e d me c h a nism    T o o l W ork T e r minals C a thode ( Ne g a ti v e t e r minal) Anode ( P ositi v e t e r minal) a r e c onnec t ed t o DC p o w er supply to c r e a t e p o t e n tial di f f e r en c e b e t w e e n w ork and t o o l. Di st a n ce b e t w e e n w ork and t o o l is kn o wn as S park g ap a n d it is filled b y diel e ct r ic flui d . 

6. W ork i ng: High v o l t a g e is applied bet w e en t ermi n als and it indu c e e l ec t ri c al f i eld in sp a rk g ap. F r ee elect r o ns o n t oo l a r e subjec t ed t o elect r o s t a tic f o r ce and h en c e th e y a r e e m i t t ed f r o m t oo l and acc e le r a t e t o w a r ds w o rk. The r e w o uld be c o llisi o n b e t w e en elect r o ns and molecul e s in dielectric. It c au s e further g ene r a tion o f ele c t r o ns be c au s e o f ioni z a tion o f diele c tric molecul e s . This c y cl i c p r o cess in c r ea s e c o nc e n t r a tion o f e l ec t r o ns in sp a rk g ap a n d when po t e n t ial di f f e r en c e is su f ficie n tly high die l ectric b r eak do w n and la r g e n o . o f ele c t r o ns will flow f r o m t oo l t o j o b and ions f r o m j o b t o t ool . Thi s mo v e m e n t o f el e c t r o n s visua l ly s ee n a s Spark and el e c t ri c al e ne r gy is dis s ip a t ed a s ther m al ene r gy o f sp a rk. With a v e r y sh o rt du r a ti o n o f sp a rk , t e m p e r a tu r e o f e l ec t r o des r ai s ed lo c ally t o mo r e than the i r n o rmal boiling poi n t and this he a t o f sp a r k m elt a ti n y bit o f m e t al f r o m w o rk. Th e mel t ed m e t als c o o ls and s o lid i fies a s ti n y parti c les in di e le c tric . The m e t al is c ar r ied a w a y due t o ci r c ul a tion o f dielectric b y m eans of pump and the p r o cess c o n tinue s .       

7. P r o c ess P a r ame t er: V o l t a g e : 4 t o 30 V Cur r e n t: .5 t o 40 A Spark g a p : . 012 5 t o0 . 12 5 mm Pulse du r a tio n : 2 t o 2000 mi c r o s e c ond M R R : 80 m m 3 – 500 mm 3 A p p l i c a t i on o f ED M :  EDM Dr i lli n g t o dri l l v e r y c ompl e x shapes. sm a ll h o l e s and EDM milling t o m achine  EDM c an be used t o m a k e parts w it h ir r egular s hape with p r e c isi o n f or f o r ging p r ess t o o l, e x trusion dies, cu t ting t o o l dies e t c .

8. Wi r e Cut EDM

9.  Wi r e EDM u s e El e ct r o th e rmal m e c hanism t o c u t el e c t ri c ally c o n du c ti v e m a t erial s . C o n s tr u ctio n :  EDM c o nsi s t N C unit to c o n t r o l c o u n t er m o v e m e n t o f w o rk, wi r e f eeding m ec h ani s m to m o v e wi r e at c o n s t a n t t ensi o n, po w er supply and diele c tric fluid suppl y . Wi r e o f . 2 t o .3 mm     diam e t er T oo l W o rk Dielec t ric C a thode ( N e g a ti v e t erminal) Anode ( P o siti v e t erminal) is de-ioni z ed w a t er applied as lo c ali z ed s t eam r a ther than subme r ging the wh o le w o rk. Wi r e f o r E D M is made o f B r a s s, c o p pe r ,  tun g s t en, and Zinc o r b r a s s c o a t ed wi r e. T h e wi r e sh o uld h a v e high t ensile s t r en g th and g oo d ele c tri c al c o ndu c tivit y .

10. W orki n g :  Dur i ng o pe r a tion wi r e m o v es al o ng p r escribed p a th and r e m o v e m a t erial f r o m w o rk. Same a s EDM p r o cess m a t erial is r e m o v ed due t o series o f disc r e t e disc h a r g e b e t w een Anode and C a t h ode in p r esen c e o f di e le c tric flui d . The place o f disch a r g e h e a t ed t o e x t r e m ely high t e mpe r a tu r e and th a t sur f ace is mel t ed and m a t erial r em o v ed. R em o v ed particl e s flushed a w a y b y flowing diele c tric fluid s .   

11. A d v a n t a g e of W i r e cut EDM:     Smo o th machine sur f ace a nd p o lishing not r equi r ed. F o rming ele c t r o de t o p r o du c t sh a pe is not r equi r ed. W ear o f ele c t r o de is negl i gibl e . P r oduc t ion r a t e is hi g h machi n e c an be easily ope r a t ed f or long ti m e. A p p l i c a t i on of Wi r e cut EDM:    I n tri c a t e c o mpone n ts f o r ele c tri c al and Ae r o sp a ce indu s tries. Mac h ining o f she e t m e t al die, e x trusi o n d i es and p r o t o type parts. C y lindri c al o bjec t s a r e c ut with high p r ec i si o n.

12. Laser beam machining ( LB M ) I t is thermal m e t al r em o v al p r ocess which uses LAS E R beam t o melt and v apor i z e par t icles o n the sur f ace of m e t allic and no n- m e t allic w or k - piece s .

13. C o n s tr u ctio n :  It c o n s i s t cylindri c al c r ys t al ru b y tub e , f la s h tub e , f o cusing lens, po w er supply s o u r ce, t o t al and partial r e flec t ing mir r o r and c oo ling s ys t e m . Ru b y is Alumin u m o xide with . 05 % C r dispe r sed and i t ’ s o ne end is bloc k ed with t o t al r e f l ecti v e mir r o r while o t h er e nd h a ving parti a lly r e flec t ed mir r o r . Fla s h tube is placed o utside ru b y c r ys t a l .  

14. W orki n g :  C a pa c i t o r b a nk is cha rg ed b y high v o l t a g e ene r gy supplied which ene r gi z e fla s h tube b y tri g ging s ys t e m . Fla s h tube f l a s hes whi t e l ig h t and C r a t o ms in ru b y c r ys t al a b s o rb this ene r gy and g e t e x ci t ed. This a t o ms p umped t o hi g h e n e r gy l e v e l and d r o p b a ck t o o riginal s t a t e. When a t o ms jump f r o m o ne t o an ot her l e v el it e mi t s ph o t o ns ( R ed   flu o r esce n t l ig h t ) . s ti m ul a tion e f f ec t . This pheno m enon is kn o wn as lasing action or  Due t o r e fle c tion this e f f e ct is enhanced and finally pho t o ns will c om e o ut f r o m partially r e flec t ed mir r o r with g r e a t i n t ensity c alled LASE R . La s er beam is f o cused with t h e h elp o f lens and w o rk is placed n ear f o c al poi n t o f len s . Due t o hi g h t e mpe r a t u r e w o rk m a t erial will m e lt and v apo r i z e .   Ru b y r o d be c o m es high e f ficie n t at low t e m p e r a tu r e . Thus it is c o n tinuous c oo led with wa t er o r liquid Nit r o g en.

15. LBM P r o c ess pa r ame t e r s:     V o l t a g e: 45 V Pul s e d u r a tion: 1 mi c r o se c o nd M R R: 0.1 m m 3 /min Sur f ace Fini s h: 0. 5 -1.2  m (CLA) A P PLIC A TI O N of LBM:    LASER LASER LASER drilling m e t al cu t ting w elding

16. A D V AN T A GE of LBM:      Small, c o mpl e x and mi c r o si z ed h o les. No di r ect c o n t act b e t w een t oo l and w o rk. Ac c u r acy is high and doe s n’t r equi r e fil l er m a t erial. Di s similar m a t erial c an ea s ily w elded. Au t o m a t ed ea s il y . DI S A D V AN T A GE:     It c an’t be u s ed t o drill deep hole s . Highly r e flec t i v e m a t erial c an’t be ef f ec t i v ely Ini t ial i n v e s tm e n t is high. machin e d. S a f e ty m u s t be f ollo w ed s tri c tly and ski l led ope r a t or r eq u i r ed.

17. Elect r on Beam M a chining ( EBM )

18. EBM is t h e r mo Electri c al p r o cess in w hi c h m a t erial is r em o v ed by hi g h v eloci t y el e ct r on b e am e mi t t ed f r o m t u ng s t en fila m e n t. Ki n e t ic ene r gy o f be am t r an s f er r ed t o w o rk, p r o du c ing he a t and m elt o r v apori z e m a t erial lo c all y .

19. Con s tr u ctio n :  It c on s i s t o f v acu u m c h ambe r , el e ct r on gun, magn e tic le n s t o f ocus be a m, d e flec t ing c o il, and w o rk t able f o r holding.  Ele c t r o n gun c o nsi s t o f grid cu p , tun g s t en fila m e n t ( c a thode), A n o d e . T h e filame n t and an o de a r e c o nne c t ed with D C po w er suppl y . W o rking:  The tun g s t en filame n t is he a t ed ab o ut 2500 - 300  C b y high v o l t a g e DC supply in o r d er t o e mit el e c t r o n s . Grid cup di r ect e l ect r o ns t o t r a v el t o w a r ds the w o rk. El e c t r ons a r e a t t r ac t ed b y t h e Anode , and pas s ed t h r ough a l r e a dy pla c ed hole without c o lliding with it. Due t o high po t e n tial di f f e r en c e elect r o ns acc e le r a t ed and i t ’ s v elocity r eaches near 2/ 3 o f lig h t v elocit y . Ele c t r o n b eam is r e f o cus e d b y elect r o magne t ic le n s s ys t e m s o t h a t be a m is di r ec t ed with c o n t r o l( typi c ally . 2 5 m m di a m e t er) t o w a r ds w o rk. F o r c o n t r o lling p a th o f cut d e flec t o r c o il is used t o d e flect ele c t r o n beam.      Kin e tic ene r gy of high v elocity be am is t r an s mi t t ed i n t o h e a t and t emp e r a tu r e o f w o rk in c r ea s ed abo v e boiling poi n t .

20. EBM p r ocess p a r am e t er:     V o l t a g e: 1, 5 0, 00 V V acuum r equi r eme n t: 1 3 3 x 1 -6 N/m2 M R R: 1.6 mm 3 /min Sur f ace Fini s h: 0. 4 -2.5  m (CLA) Appli c a ti o n: T o drill holes in p r es s u r e di f f e r e n tial d e vice and t o c o ndu c ti v e a nd h igh mel t ing poi n t m a t erial s . Ad v a nt a g e: machine low ther m al    D r ill v e r y sm a ll h o le with high acc u r ac y . B r i t tle m a t erial c an be e a sily machin e d. S e t up c an be au t o m a t ed ea s il y . Di s a d v a n t a g e:    V acuum chamber is es s e n tial E quipm e n t c o s t is high. Low MRR and skilled o pe r a t o r r equi r ed.

21. E lect r ochemi c al Machining ( E CM)

22. Serv ( c athode) n flow of e l e c tr o l yte D C P ump power su p ply + fo r T ank Ele c tr o l y t e E CM is m e t al ele c t r o pl a tin g . r e m o v al p r ocess based on p rin c iple of r e v e r se F i lt e r Tool u s e d Con s tant t oo l fe e d 1-- --- --, D o\ v t . Motor for pun 1 p R es e rv o i r E l e c t r olyte

23. Con s tr u ctio n :  It c o n s i s t c a t hode( t oo l), A node( w o rk ) , Se r v o m o t o r t o c o n t r o l t oo l f e ed, Ele c t r o l y t e t ank and i t ’ s ci r cu l a tion ar r an g eme n t, D C po w er Se r v o mo t o r c o n t r o lled the f eed o f t ool . Pump is pla c ed f or p r ovi d ing s t r ong s t r eam o f el e c t r ol y t e. suppl y .   W orkin g :  D C po w er s u pply p r ovides cur r e n t 5 t o 4000 A a t 5 t o 30 V f o r a c r o ss t h e g ap o f . 05 t o 0.07 m m be tw e en t oo l and w or k . Elec t r ol y t e f l o w s th r o ugh this g ap a t v elocity 3 t o 6 m / s .  Cur r e n t s t ar t ed flowing t h r o ugh el e ct r o l y t e with po s iti v ely ch a r g ed ions a t t r ac t e d t o w a r ds the t oo l and ne g a ti v ely ch a r g ed ions a t t r ac t ed t o w a r ds w o rk.  Due to this flow e l ec t r o chem i c al r e action t a k es place and m e t al r em o v es in f o rm slud g e . This slud g e is t a k en a w a y f r o m g ap b y s t r o ng s t r eam o f ele c t r o l y t e . 

24.  F oll o wing r e a ctions t a k es pla c e while ma c hining of pu r e i r on th r ough E C M using NaCl + H 2 O as el e ct r ol y t e.

25. E CM P r o c ess P a r ame t er:      V o l t a g e: 4 t o 30 V Cur r e n t: 50 t o 40 00 A M R R: 16 m m 3 /min Sur f ace Fini s h: 0. 1 -2.5  m Gap: .025 t o 0.75 mm (CLA) P r operties of El e ct r ol y t e: Ele c t r o l y t e p r ovides s e v e r al func t ions li k e c o mpl e t e the ci r cu i t, R em o v e m a t erial f r o m cu t ting r egion b y p r es s u r e, C a r r y a w a y he a t t o g ene r a t ed. High thermal and E l ec t ri c al C o ndu c tivity Low v is c o sity Cheaper a nd A v ailable Non c o r r o si v e and Non t o xic Chemi c ally S t able a t p r o cess t emp e r a tu r e. be     

26. Elec t r ochemi c al Grinding ( E C G) or Elect r ol y tic Grinding or Ano d ic Machin i ng

27.  It is c o mbin a tion o f c o n v e n tional me c hani c al grinding and e le c t r o ch e mi c al machin i ng in w hi c h m a t erial r em o v ed b y ele c t r o l y tic activi t y . I n t his p r ocess mo s tly m a t erial r e m o v ed b y el e c t r oche m i c al de c ompo s it i on and r emaining m a t erial is r em o v ed b y ab r a s ion o f m e t al.  E C G is widely u s ed be c au s e it gi v es bur r s f r ee s ur f ace w ithout p r o du c ing he a t a nd a f t er E C G, a n y se c o nda r y machin i ng o pe r a tion not r equi r ed.

28. Con s tr u ctio n :  It c on s i s t o f m e t allic grinding w h eel a s c a t h ode, W or k -pi e ce a s anode, Ele c t r o l y t e t ank and ci r cu l a tion s ys t e m . Grin d ing wh e el is maid s u ch th a t dia m o nd o r aluminum o xide p articles e mbed d ed in it and it slig h tly p r o jec t ing o ut f r o m t h e sur f ace s o th a t t h e y t ouch w ork sur f ace with a v e r y li t tle p r es s u r e . T his ab r asi v e parti c les p r e v e n ting di r ect c o n t act b e t w een wheel and w o rk pie c e. As Elect r o l y t e , non c o r r o si v e s a lt s o lut i o n is used w i th wa t e r . It w o r k s as both Ele c t r o l y t e and c oo la n t .   W orking:  DC po w er is supplied b et w een elect r o des and Grin d ing wh e el s t art r o t a ting b y means o f mo t o r . Pump ci r cu l a ting ele c t r o ly t e F r o m r e se r v o i r t ank t o machin i ng plac e . When el e c t r o l y t e e n t r apped in sm a ll c a vities b e t w ee n w o rk and a b r a s i v e particl e s it f o rms ele c t r o l y t e ce l l . Cur r e n t s t ar t ed flowing grinding wheel (C a thode) t o w o rk (Anode) O xide film f o rms o n sur f a c e o f w o rk d u e t o ele c t r o c hemi c al o xid a tion and this film is r e m o v ed b y p r o jec t ing a b r a s i v e particl e s, which r e sults in ac c u r a t e sur f ace finish.   

29. A p p l i c a t i on:  F o r grind i ng C a rbide t oo ls, re f r ac t o r y m e t als and C o balt b a s ed alloy E C G is used. A d v a n t a g e:    P r ocess is ind e pe n de n t of m a t erial ha r dn e ss and s t r en g t h . Not c o mpl e t ely depen d s o n ab r a s i v e p r o cess. W o rk is not s ubjec t ed t o a n y m e chani c al di s t o rtion and no he a t g ene r a tion. Hi g h s ur f ace finish and t o o l w ear is ne g li g ibl e . Rapid M R R .   Disad v a n t a g e:    P o w er c o nsum p tion is mo r e and High C a pi t al c o s t. Not appli c able f o r no n - c o ndu c ti v e w o r k -pie c e. It is not s ui t able f o r s o ft m a t erial s .

30. Plasma A r c Machining ( P AM)

31.  It is me t hod o f m e t al cu t t ing with a r c o f pla s ma( jet o f high v el o ci t y ioni z ed g a s ) th a t r em o v es m a t erial f r o m w o rk-pie c e.  A t v e r y hig h er t e mpe r a tu r e a t o ms o f g as be c o m e ioni z ed and this s t a g e o f g as is kn o wn a s Pl a sm a .

32. Con s tr u ctio n :   Plasma t o r ch ma k es plasma and di r e c t it f or cu t ting. Plasma t o r c h c on s i s t g a s chambe r , N o zzle as Anode and T u ng s t en el e ct r ode as C a thode and p o w er suppl y . A r g on, n i t r o g en, h y d r o g en, o r co m p r essed air i n t r oduced a r ound ca thode.  W orki n g Pr i nci p le:  I n g as cha m ber high v elocity a r c is g e n e r a t ed b e t w e e n Anode and C a thode. G a s mole c ules a r e c ollide with high v elocity elect r ons of a r c and d u e t o this g a s g ets ioni z ed and la r g e amou n t o f he a t en e r gy lib r a t e d .  This high v e locity s t r eam o f hot i o ni z ed g as ( Plasma) is d i r e c t ed o n the w ork - pie c e t o melt the m a t e r ia l .

33. P AM P r o c ess P a r ame t er:      V ol t a g e: 30 -2 5 V Cur r e n t: U p t o 6 A P ow er: 2 -2 K W V e l ocity of plas m a j e t: 5 m / s MRR: 1, 5 0, m m 3 /m i n A d v a n t a g es:    A n y e l ectri c al l y c on d u c ti v e m a t er i al machined r e g a r dle s s i t ’ s ha r d n es s . Doe s n’t r equi r e a n y su r f ace p r epa r a ti o n. It has h igh c u t ting r at e. Disad v a n t a g e:     P ow er c onsum p tion is v e r y high. High equipme n t co s t. It p r od u ced t ape r ed sur f ace. Noi s e p r o t ection is r equi r ed.

34. Chemi c al Machining (CM)

35.  I n Chemi c al Machining p r ocess m at erial is r e m o v ed b y chemi c al diss o lution using ch e m i c al r e a g e n ts o r e t ch a n ts ( A cids o r A l k aline s o lution s ) . Ch e m i c al r eaction t a k es pla c e b e t w een w ork sur f ace and e t c ha n ts r esulting i nt o r em o v al o f m a t erial f r om sur f ac e .   The s ur f ace which e t c h ed a w a y , e x po s ing p r ocess is c o n tinued till the desi r ed amou n t Cl a ssifi ca tion o f Ch e mi c al Ma c hining: the l o w er l a y e r s and o f m a t e r ial r em o v e d .     Chem i c al Chemi c al Chemi c al blan k ing M i lling eng r a ving

36. S t e p s f or C M : 1) R esidual s t r ess r elieving Cle a ning the w ork pie c e Masking E t ching D e - masking 2) 3) 4) 5)

37. A p p l i c a t i on o f CM:  C M is used a s chemi c al blanking f o r burr f r ee e t ch i ng o f p ri n t ed ch e mi c al pri n t ed ci r cu i t bo a r ds, de c o r a ti v e panel s .  Chemi c al milling is c o mm o nly used in ae r o sp a ce indu s t r y sh a ll o w l a y e r s o f m a t erial f r o m la r g e ai r c r a ft c o mpone n ts skin panels and airf r ame parts. A d v a n t a g e : t o r e m o v e li k e mis s ile  It doe s n’t d i s t o rt t h e w o rk and all the f aces of w o rk m a ch i ned simul t ane o usl y . Low s e tup, mai n t enance and t oo ling c o s t. It c an be used t o machine c o mp l e x p r o files design part s . Imp r o v es p r o du c tivit y .   o f deli c a t e and i n tri c a t e  Disad v a n t a g e :    La r g e t ank and la r g e fl o o r a r ea r equi r ed. High o pe r a tion c o s t . Chemi c als used in p r o cess m a y be dan g e r o us t o healt h .

38. Ult r asonic Grinding or Ul t r asonic Ma c hining (U S M) or Ult r asonic impact Grinding

39. It is m e c h ani c al m a t erial r e m o v al p r ocess in whi c h m a t erial is r em o v ed b y r ep e ti t i v e impact o f ab r a s i v e slur r y o n w o rk s ur f ace, b y using hi g h f r equen c y o scill a tion o f sh a ped t oo l.

40. Con s tr u ctio n :  It c o n s i s t o f U l t r a so nic g ene r a t o r and t r an s du c e r , C o nc e n t r a t o r , t oo l, Ab r a s i v e slur r y and i t ’ s f eed me c hani s m, and t oo l f eed me c hani sm . C o nc e n t r a t o r is t oo l c o ne which made f r o m ti t anium o r SS. T oo l is a t t a c hed t o b a se o f c o nce n t r a t o r b y mean o f sil v er b r azing or sc r e w s . T o o l is shaped a s app r o xi m a t e mir r or ima g e o f c a vity desi r e d . The g ap b e t w een t oo l and w o rk is ab o ut . 2 t o .1 m m. Ab r a s i v e slur r y is mixtu r e o f ab r a s i v e g r ains and c arri e r fluid w hi c h is p r o v ided bet w e en t oo l a nd w o rk-pi e ce. Gene r ally w a t er is u s ed as c ar r ier fluid.     W orkin g :  The ult r a so nic t r an s du c er c o n v erts e lec t ri c al en e r gy i n t o ult r a so nic w a v es o r vib r a tions using magn e t o s tri c ti v e e f f ec t s . T oo l vib r a t es longitudinal l y a t 2 t o 3 k H z with a mpli t ude . 2 mm p r essed o n t h e w ork sur f ace with li g h t f o r c e .   C o nc e n t r a t o r in c r ea s e t h e amplitu d e of vib r a ti o n in o r der to gi v e r equi r ed f o r ce amplitu d e r a tio.

41.  Th e ab r a s i v e parti c le in f orm o f ab r asi v e slur r y is c o n ti n uous c i r c u l a t e b e t w e en t o o l and w o rk. T h e t oo l p er f o rms hampering action on ab r a s i v e particl e s . The vib r a tion o f t oo l tip acc e le r a t es the ab r a s i v e p a rti c les a t hi g h r a t e  and it imparts the ne c es s a r y f o r ce f o r cu t ting action.  The t oo l is g r adua l ly m o v e s down mai n t ain c o n s t a n t g a p . by m e a ns of t oo l f eed m e chan i sm to US M P r o c e ss P a r a m e t e r :      Vib r a tion f r equen c y: 1 5 t o 3 kHz Vib r a tion amplitu d e: 2 5 t o 10  m Gap: . 2 t o .1 mm Sur f ace finis h : .2 t o .8  m ( C L A) M R R: 30 m m 3 /min

42. A p p l i c a t i on o f US M:  It is u s ed f o r machin i ng o f ha r d and b r i t tle m a t erial li k e c e r ami c s, bo r o n c arbide, ti t anium c arbid e .  USM enables a de n ti s t t o drill a hole o f a n y sh a pe o n t e e th painles s l y . A d v a n t a g e o f US M:   No n - c o ndu c ti v e m a t erials c an al s o machin e d. The r e is no a n y chan g e in mi c r o s tru c tu r es, p h y si c al or ch e m i c al p r o perti e s . B e t t er sur f ace finish and hi g her s tru c t u r e i nt egr i t y . Noi s eless o pe r a tion.    W o rk pie c e ha r der than 6 H R C li k e c arbide, Ce r amics machin e d by US M . Disad v a n t a g e o f USM :     Low M RR. High po w er c o nsum p tio n . High t oo ling c o s t and it w ea r s r apidl y . Not sui t able f o r s o ft m a t erials

43. F ac t o r s a f f e c t i ng MRR and sur f ace fi n ish in USM:       T oo l ampl i tude and f r equen c y . T oo l shape. Ab r a s i v e g r ain si z e. Ab r a s i v e c once n t r a tion. W o rk h a r dnes s - t oo l ha r dness r a tio. F eed f o r ce.

44. Ab r asi v e j e t m a chining or Mic r o-ab r asi v e Bla s ting

45. Ab r a s i v e jet ma c hin i n g is m e ch a ni c al en e r gy based un c o n v e n tional machin i ng p r o cess u s ed t o r e m o v e u n w a n t ed m a t erial f r o m a gi v en w o rkpie c e .

46. Con s tr u ctio n :  It c o n s i s t o f C o mp r es so r ( T o p r es s uri z e t h e g as ) , Fil t e r , mix i ng ch a mbe r , H o ppe r , Vib r a t o r , N o z z le, P r es s u r e g au g e and flow r egul a t o r . The n o z z le is made o f a ha r d m a t erial li k e tun g s t en c arbid e .   Ab r a s i v e u s ed a r e alum i num o xi d e, Sili c on c arb i de, or Sodium bi c arb o n a t e . The g a s es c o mmonly u s ed a r e ai r , N 2 , C O 2 . H o pper is placed abo v e mix i ng chamb e r f o r f eeding purpo se . Vib r a ti n g devi c e pla c ed be l ow mi x ing c h am b er t o vib r a t e mi x t u r e of ab r a s i v e and g a s .    W orkin g :   Fi r s t d r y air o r g as is fil t e r ed and then it c o mp r es s ed b y c o mp r es so r . A p r essu r e g au g e and flow r eg u l a t or c o n t r ols t h e p r ess u r e and r eg u l a te the flow o f the c o mp r es s ed ai r . C o mp r es s ed air e n t e r ed i n t o the mixing cham b er whe r e it mi x ed with ab r a s i v e particl e s . 

47.  The n mixtu r e pas s es t h r o ugh n o z zle w he r e hi g h v eloci t y fi n e ab r a s i v e j e t is p r o du c ed. The n o z z l e in c r ea s es v el o ci t y ab o ut 20 t o 40 m / s at the e xpense o f i t ’ s p r es s u r e .  As a r esult o f r epe a t ed impact m a t e ri a l r em o v ed f r o m w o rk due to by e r o si o n . A g a i n n e w sur f a c e e xpo s ing e r o si o n . A JM P r o c e ss P a r a m e t e r : a n d so on m a t erial r em o v ed     Ab r a s i v e si z e: 2 5  m N o z z le diam e t er: . 1 3 t o 1 .2 mm M R R: .8 m m 3 /min Sur f ace Finish: . 5 - 1 .2  m (CLA) A p p l i c a t i on:    D r illin g , Cle a nin g , and poli s hing o f ha r d sur f ace. T o machine i n tri c a t e sh a pes which is di f ficult t o machin e . Ai r c r a ft fuel s ys t em, Medi c al appliances and H y d r aulic v al v e s .

48. A d v a n t a g e o f A b r asi v e J e t Machi n i n g:      N o he a t is g ene r a t ed in w o rk. So it is sui t able f o r N o p h y si c al c o n t act b e t w een t oo l and w o r k . Thin and f r agile m a t erials al s o machin e d. Low i n v e s t m e n t . Smo o th sur f ace finis h . he a t sen s iti v e m a t erial s . Disad v a n t a g e :    Low M R R . Ab r a s i v e p o w der c annot be r euse d . N o z z le li f e is less and mai n t enance o f n o z z le r equi r e d . F ac t o r s a f f e c t i ng per f or m ance o f A JM:      Ab r a s i v e g r ain si z e and I t ’ s ma s s flow r a t e M i xing r a tio. V elocity o f ab r a s i v e particl e s . Gas p r es s u r e . N o z z le tip di s t anc e .

49. Comparison b e t w een v arious No n -c o n v e n tion a l Machining P r ocess

50. S u r f ace finish m ( CLA) P o w e r c o n s u m p ti o n T o o li n g Co s t I n v e s tm e n t c o s t M R R P r o ce ss Me d i u m E f f ic ien cy L i qu i d die l ect ri c EDM 0.2-1.2 800 L o w Hi gh Med i um Hi gh E CM E l ect r o l y t e 0.1-2.5 1500 Medium Medium V e r y high L o w Hi gh (Chemi c al c o s t) L i qu i d c h e mi c al CM 0.5-2.5 15 l o w Medium Medium LBM Air 0.5-1.2 0.1 V e r y l o w L o w L o w V e r y high EBM V acuum 0.5-2.5 1.6 L o w L o w Hi gh V e r y high P AM A r g on R ough 75000 V e r y l o w L o w V e r y l o w V e r y l o w Ab r a s i v e i n w a t er USM 0.2-0.5 300 L o w L o w L o w Hi gh Ab r a s i v e i n g as A JM 0.5-1.2 0.8 l o w l o w V e r y l o w Hi gh