Surface Roughness Optimization of EDM Process of Hastelloy C22 ...

1st International Conference o f Advanced Materials and Manufacturing Technologies (ICAMT’17) 25-27 October 2017, Safranbolu, Karabuk, Turkey

Surface Roughness Optimization of EDM Process of Hastelloy C22 Super Alloy Engin NAS1*, Hasan GOKKAYA2, Sitki AKINCIOGLU3, Gul§ah AKINCIOGLU4 1 University o f Duzce, Cumayeri Vocational School, Endustriel Molding, 8 1 7 0 0 , Duzce - TURKEY, e-mail:[email protected] (corresponding author) 2Machine Engineering, Karabuk Universty, Karabuk 78600, Turkey, e-mail: [email protected] 3University o f Duzce, Gumu§ova Vocational School, Mechine Design, 8 1 7 0 0 , Duzce - TURKEY, e-mail: [email protected] 4University o f Duzce, Gumu§ova Vocational School, Mechine Design, 8 1 7 0 0 , Duzce - TURKEY, e-mail: [email protected]

Abstract

- In this study, the super alloy Hastelloy C22 abrasion process was conducted with a copper electrode in electro erosion machine tools. The parameters used in the experimental study were three different pulse durations (10, 20 and 30 ps), waiting time (5, 10 and 15 ps) and discharge currents (5, 10 and 15 amps). As a result of the work done, the minimum mean surface roughness value was measured as 20 ps in the pulse duration, 10 ps in the wait time and 2.86 pm in the 5 amp current. The highest average surface roughness value was found to be 10 ps, 10 ps in the waiting period and 4.07 pm in the 15 amperes current.

p e r fo r m e d b y

Key Words: Electro-Erosion Processing, Roughness, Machinability, Hastelloy C22

th e p r o d u c ti o n o f m o ld s [3, 5 ]. M e ta l r e m o v a l i n E D M is

th e r m a l e n e rg y ,

so

it is

c a te g o r iz e d

as

th e r m a l p r o c e s s in g m e th o d s . T h e r e is n o e f fe c t o n th e p r o c e s s in g p e r fo r m a n c e o f th e m a te ria l s tiffn e s s , to u g h n e s s a n d s tr e n g th o f th e m a te ria l to b e tr e a te d , w h e r e a s th e m e ltin g

te m p e ra tu r e

and

th e r m a l

c o n d u c tiv ity

of

th e

m a te ria l to b e tr e a te d a re in f lu e n c e d [4]. I n th is te c h n o lo g y , w h e r e e le c tr ic a l s p a r k s a re u s e d f o r m a te ria l a b ra s io n , th e r e a re n o m e c h a n ic a l s tre s s e s , t o r s i o n a n d v ib r a t i o n p r o b le m s d u r in g p r o c e s s in g a s th e e le c tr o d e a n d w o r k p ie c e d o n o t t o u c h e a c h o th e r. T h e s e p r o p e rtie s m a k e it p o s s ib le to u s e e le c tr o e r o s io n a s a n in d is p e n s a b le t e c h n o lo g y e s p e c ia lly i n

Surface

a c h ie v e d b y m e ltin g a n d e v a p o r a tin g w o r k p ie c e m a te ria l [1, 6 ]. A t th e s a m e tim e th e e le c tr o d e is w o r n w h ile th e

I. I N T R O D U C T I O N

c h ip is r e m o v e d f r o m th e w o r k p ie c e d u r in g m a c h in in g [7,

A lo n g w i t h th e d e v e lo p m e n t o f p r o d u c ti o n te c h n o lo g ie s ,

is n o t s u ffic ie n t, s h o rt c ir c u it a n d a r c - ty p e p u ls e s b e tw e e n

th e u s e o f n e w m e th o d s i n th e m a n u f a c tu r e o f m a te ria ls

th e

w h i c h a re d if f ic u lt to p r o c e s s h a s b e c o m e w id e s p r e a d a n d

e x c e s s iv e lo c a l c o n ta m in a tio n o f th e p r o c e s s in g w a s te s

e le c tr ic e r o s i o n is o n e o f t h e m [1]. T h e b a s is o f th e p r o c e s s

d u r in g p r o c e s s in g [9]. A s a re s u lt, d e c r e a s e i n w o r k p ie c e

o f m a te ria l r e m o v a l b y e le c tr ic a l s p a r k is b a s e d o n 1 7 0 0

m a c h in in g s p e e d (E A H ), in c r e a s e i n e le c tr o d e w e a r ra te

8 ]. I f th e s h a p e a n d s p e e d o f th e d ie le c tr ic f l u id a p p lic a tio n

w o r k p ie c e

and

th e

e le c tr o d e

w ill in c r e a s e

d u e to

y e a rs . T h e u s e o f t h e e le c tr ic a l a rc f o r w e ld in g w a s c a r r ie d

(E A H ),

o u t b y M e r ite n s i n 1 8 8 1 . T h e c u r re n t u s e o f th e E D M

r o u g h n e s s (R a ) is o b s e rv e d . N o n - to le r a n c e d im e n s io n s o f

( E le c tr ic a l D is c h a rg e M a c h in e ) is b a s e d o n th e e le c tro

th e w o r k p ie c e a re o b ta in e d . [8, 10, 11]. T h e s u c c e s s o f th e

e ro sio n

s c ie n tis t

d ie le c tr ic f lu id a p p li c a t io n d e p e n d s o n th e d ie le c tr ic f lu id

L a z a r e n k o a n d h is w if e i n 1 9 4 8 [2]. T h e r a te o f p r e fe r e n c e

a p p li c a t io n ra te , th e s p e e d a n d th e w a itin g tim e b e tw e e n th e

f o r s o m e in c r e a s e s a n d d e c r e a s e s o v e r tim e

tw o d is c h a rg e s . T h e s h o r te r th e tim e , th e s h o r te r th e c ir c u it

m a c h in e

m a n u f a c tu r e d

by

R u s s ia n

sh o w ed a

s te a d y in c r e a s e o f 3 0 % p e r a n n u a l a f te r th e 1 9 7 0 s [1 ,2 ].

re la tiv e

w ear

(B A )

and

w o r k p ie c e

s u rfa c e

[1 2 ]. H a s te llo y C 2 2 is a s u p e r a llo y w i t h h i g h c o r ro s io n re s is ta n c e i n a c id ic e n v ir o n m e n ts a n d s e a w a te r. H o w e v e r ,

E le c tr o - e r o s io n m a c h in in g is a n u n u s u a l m a n u f a c tu r in g

b ecau se

m e th o d u s e d to p r o c e s s g e o m e tric a lly c o m p le x a n d r ig id

of

th e

m a c h in a b ility

m a te ria ls [3]. A l th o u g h th e e le c tr ic e r o s i o n m e th o d u tiliz e s

m a c h in in g

e le c tr ic e n e r g y a s e n e rg y , th e m a te ria l r e m o v a l p r o c e s s is

is

h ig h

n ic k e l

d if f ic u lt

m e th o d s .

[1 3 ].

to

c o n te n t a c h ie v e

H ig h

in by

th e

a llo y ,

c o n v e n tio n a l

t e m p e ra tu r e s

d u r in g

m a c h in in g o f s u p e r a llo y s d e s tr o y c u ttin g to o ls , d is r u p t

153


p r o d u c t q u a lity c u ttin g

to o l.

a n d in c r e a s e th e

The

u se

of

F ig . 2 A 10 m m d ia m e te r e le c tr o ly tic c o p p e r

am o u n t o f co nsum ed

n o n - tr a d itio n a l

m e th o d s

fo r

B. Electro Erosion Machine

p r o c e s s in g s u c h d i f f ic u lt- to - h a n d le m a te ria ls m a y in c re a s e p r o d u c t q u a lity a n d re d u c e p r o d u c ti o n c o s ts [1 3 ].

I n th e e x p e r im e n ta l w o rk , K in g b r a n d Z N C

- K -3 2 0 0

p lu n g e e r o s i o n m a c h in e w a s u s e d . T h e c o n tr o l p a n e l o f th e u s e d d e v ic e is s h o w n i n F ig .3 .

I n th is s tu d y , th r e e d if f e r e n t p u ls e d u r a tio n s (1 0 , 2 0 a n d 3 0 q s), w a itin g tim e s (5 , 10 a n d 15 q s) a n d d is c h a rg e c u r re n ts (5 , 10 a n d 15 q s) w e re m e a s u r e d i n d if f e r e n t p r o c e s s in g p a r a m e te r s w i t h H a s te llo y C 2 2 s u p e r a llo y e le c tro e r o s io n c o u n te r, a n d th e p a r a m e te r s a f fe c tin g s u rfa c e r o u g h n e s s w e r e in v e s tig a te d . II. M E T H O D

A. Material and Electrode H a s te llo y C 2 2 is a m a te ria l w i t h re s is ta n c e to tin g lin g , c r a c k c o r r o s i o n a n d s tre s s c o r r o s i o n c ra c k in g . H a s te llo y C 2 2 h a s e x c e lle n t re s is ta n c e to a w id e ra n g e o f c h e m ic a l e n v ir o n m e n ts

su ch

a s f e rr ic

c h lo r id e ,

F ig . 3 T h e c o n tr o l p a n e l o f th e d e v ic e

c o p p e r c h lo rid e ,

C. Test Parameters

c h lo rin e , d is tu r b e d s o lu tio n s , fo r m ic , a c e tic a c id , a c e tic a n h y d rid e ,

s e a w a t e r a n d b r in e

s o lu tio n s .

[1 3 ]. I n th e F o r th e H a s te llo y C 2 2 s u p e ra llo y , 2 7 e x p e r im e n ts w e re

e x p e r im e n ta l s tu d y , H a s te llo y C 2 2 s u p e r a llo y 8 0 m m i n d ia m e te r (F i.1 ) a n d 10 m m d ia m e te r (F ig .2 ) e le c tr o ly tic c o p p e r w i t h a d e n s ity o f 8 .9 g r / c m 3 w e r e u s e d . c h e m ic a l c o m p o s itio n o f H a s te llo y

C 22

c a r r ie d o u t b y d e te r m in in g th r e e d if f e r e n t p u ls e (T o n ) tim e s (1 0 , 2 0 a n d 3 0 q s ), a w a itin g (T o ff) tim e (5 , 10 a n d 15 q s)

The

a n d a d is c h a r g e c u r re n t (5 , 10 a n d 15 a m p e re s )

s u p e r a llo y is

s h o w n i n T a b l e 1. III. R E S U L T S TABLE I E x p e r im e n ta l w o r k w a s c a r r ie d o u t a t r o o m te m p e ra tu r e

T h e c h e m ic a l c o m p o s it i o n o f H a s te llo y C 2 2 s u p e r a llo y

Ni 58,2

Cr 21,28

Mo 12,94

Fe 4

W 2,87

(F ig .4 ) a n d th e a v e r a g e s u rfa c e ro u g h n e s s v a lu e s o b ta in e d a re g i v e n i n T a b l e 2.

Diger 0,71

F ig . 1 H a s te llo y C 2 2 s u p e r a llo y 8 0 m m i n d ia m e te r u s e d i n th e e x p e r im e n ta l w o r k

F ig . 4 P h o to d is p la y o f p r o c e s s i n g m o m e n t i n p lu n g e e r o s i o n d e v ic e

154


T A B L E II

p e r io d s in c r e a s e s th e p a r a m e te r s

____________ p a r a m e te r s Vault Ex durati Demurr Curre nt age on P. Toff Ampe No Ton r (A) (M s) (Ms) 1 10 5 5

a p p r o p ria te ly o n th e t r e a te d s u rfa c e [1 7 ].

u se d in Avg. surface roughn ess Ra (Mm) 2.93

th e e x p e rim e n ts .____________ Vault Avg. surface Ex durati Demurr Curre nt age on P. Toff Ampe roughn ess Ra No Ton r (A) (Ms) (Mm) (Ms) 15 20 10 15 3.92

2

10

5

10

3.13

16

20

15

5

3.45

3

10

5

15

3.40

17

20

15

10

3.49

4

10

10

5

2.93

18

20

15

15

3.95

5

10

10

10

3.47

19

30

5

5

2.97

6

10

10

15

4.07

20

30

5

10

3.44

7

10

15

5

3.27

21

30

5

15

3.59

8

10

15

10

3.07

22

30

10

5

3.47

9

10

15

15

3.20

23

30

10

10

3.70

10

20

5

5

2.93

24

30

10

15

3.84

11

20

5

10

3.60

25

30

15

5

3.21

12

20

5

15

3.63

26

30

15

10

3.57

13

20

10

5

2.86

27

30

15

15

3.60

14

20

10

10

3.83

a)

by

s u rfa c e ro u g h n e s s v a lu e i n s o m e

A v e r a g e s u rfa c e r o u g h n e s s m e a s u r e m e n ts a c c o r d in g to th e

c a u s in g

th e

m e ta l

to

re -s o lid if y

m o re

C u rren t 5 (Amper)

Dem urrage, (Toff)

Ton(10^s)

b)

Ton(20^s)

Ton(30^s)


T h e m e a n s u rfa c e r o u g h n e s s v a lu e s g i v e n i n T a b le 2 w e re p l o tt e d a c c o r d in g to th e v a lu e s o f th e w a itin g tim e (T o ff), th e

d u r a tio n

ro u g h n e s s

(T o n )

v a lu e s

and

a m p e ra g e .

g e n e r a lly

A v e rag e

in c re a se d

w ith

s u rfa c e

in c r e a s in g

c u r re n ts i n e x p e r im e n ts w i t h 10, 2 0 a n d 3 0 p s s w e e p tim e s a n d 5, 10 a n d 15 p s s ta n d b y .

T h e h ig h e s t a v e r a g e s u rfa c e

ro u g h n e s s v a lu e w a s a c h ie v e d a t 15 A m p e r e s c u r r e n t a n d

Ton(10^s)

10 p s a t 10 p s s ta n d b y tim e . T h e m in im u m a v e ra g e s u rfa c e

Ton(20^s)

Ton(30^s)

ro u g h n e s s v a lu e w a s 2 0 p s p e r p u ls e d u r a tio n a n d 5 a m p e re c u rre n t.

It

w as

d e te r m in e d

th a t

th e

a v era g e

s u rfa c e c)

ro u g h n e s s v a lu e s in c r e a s e d w i t h in c r e a s in g c u r re n t v a lu e (F ig .

6 ),

w h ile

th e

a v era g e

s u rfa c e

ro u g h n e ss


v a lu e

d e c r e a s e d w i t h d e c r e a s in g c u r re n t [1 4 , 15]. W h e n th e g r a p h i n F ig .5 is e x a m in e d , th e b e s t m e a n s u rfa c e ro u g h n e s s v a lu e (a t 2 0 p s v a u lt d u r a tio n , 10 p s d e m u rra g e a n d 5 A c u r re n t) is 2 .8 6 p m . A s th e a m p e r e c u r r e n t v a lu e s in c re a s e , s u rfa c e r o u g h n e s s v a lu e s in c re a s e . T h e h ig h e s t s u rfa c e ro u g h n e s s v a lu e s w e r e d e te r m in e d a t 2 0 a m p e re c u rre n t. I n o r d e r to o b ta in g o o d s u rfa c e ro u g h n e s s , th e a m p e r e c u r re n t m u s t b e re d u c e d .

Ton(10^s)

I n g e n e ra l, i t is k n o w n t h a t w h e n t h e d u r a tio n o f th e s e s s io n

Ton(20|is)

Ton(30^s)

a n d th e w a itin g tim e a re fix e d , th e s u rfa c e r o u g h n e s s v a lu e in c r e a s e s w i t h th e in c r e a s e o f th e a m p e r a g e v a lu e [1 6 ]. I n th is s tu d y , it is c o n s id e r e d t h a t m o re t h a n o n e v a r ia b le

F ig . 5 C h a n g e o f s u rfa c e r o u g h n e s s a c c o r d in g to c u rre n t, a )

a f fe c ts th e s u rfa c e r o u g h n e s s v a lu e s . I t is b e li e v e d t h a t th e

5 a m p e r, b ) 10 a m p e r a n d c ) 15 a m p e r

c o o lin g e f f e c t o f th e d ie le c tr ic f l u id d u r in g th e h i g h - d u ty

155


W h e n th e d a ta o b ta in e d a c c o r d in g to th e p u ls e d u r a tio n s in F ig u r e 6 a re e v a lu a te d ( a c c o r d in g to th e p u ls e d u r a tio n o f

W hen

10, 2 0 a n d 3 0 p s), th e h i g h e s t s u rfa c e r o u g h n e s s v a lu e s

a c c o r d in g to th e v a u lt d u r a ti o n ( T o ff), th e h ig h e s t v a lu e s

w e r e m e a s u r e d a s 4 .0 7 , 3 .9 5 a n d 3 .8 4 p m re s p e c tiv e ly . T h e

w e r e m e a s u r e d a s 3 .5 9 , 4 .0 7 a n d 3 .9 5 p m i n th e w a itin g

l o w e s t s u rfa c e r o u g h n e s s v a lu e w a s m e a s u r e d a s 2 .9 3 , 2 .8 6

p e r io d o f 5, 10 a n d 15 p s, re s p e c tiv e ly . T h e h ig h e s t s u rfa c e

a n d 2 .9 7 p m r e s p e c tiv e ly .

r o u g h n e s s v a lu e w a s m e a s u r e d a s 2 .9 3 , 2 .8 6 a n d 3 .0 7 p m .

a)

s u rfa c e

ro u g h n e s s

w e re

e v a lu a te d

Toff(10^s)

Toff(15^s)

5Amper

10Amper

15Amper

V ault duration, T on (20 ms)

Toff(5^s)

Toff(10^s)

5Amper

Toff(15^s) c)

c)

r e s u lts


Toff(5^s)

b)

th e

10Amper T off 15

15Amper

ms


5Amper Toff(5^s)

Toff(10^s)

10Amper

15Amper

Toff(15^s) F ig .

F ig . 6 C h a n g e o f s u rfa c e r o u g h n e s s a c c o r d in g to v a u lt

7

C hange

of

s u rfa c e

ro u g h n e ss

a c c o r d in g

D e m u r ra g e , a ) 5 T o ff, b ) 10 T o f f a n d c ) 15 T o f f

d u r a tio n , a ) 10 ^ s , b ) 2 0 ^ s a n d c ) 3 0 ^ s

156

to


IV .

[12] Cogun, C., Keeping electric discharge machining under control. Machine Design. Vol. 62. 1990: Penton Media, Inc.,. [13] Akincioglu, S., Gokkaya H., and Uygur I., The effects of cryogenictreated carbide tools on tool wear and surface roughness of turning ofHastelloy C22 based on Taguchi method. The International Journal of Advanced Manufacturing Technology, 2016. 82(1-4): p. 303-314. [14] Qo§kun, I. and I§ik F.M., Turning with electro-erosion method. Journal of Politechnic, 2008. 11(4). [15] Sen, B., et al. Developments in electric power supply configurations for electrical-discharge-machining (EDM). in Power Electronics and Drive Systems, 2003. PEDS 2003. The FifthInternational Conference on. 2003. IEEE. [16] Salman O., Kayacan .C.M., Investigation of surface roughness of hardened powder metal material processed with EDM. Engineer Machine, 2004. 47(560): p. 16-22. [17] Lee, H.T., Hsu, F. C., Tai, T. Y.,, Study ofsurface integrity using the small area EDMprocess with a copper-tungsten electrode. Materials Science and Engineering A, 2004(364): p. 346-356

R E S U L T S a n d D IS C U S S IO N

A s a r e s u lt o f th e w o r k d o n e ;

•

T h e lo w e s t s u rfa c e r o u g h n e s s v a lu e w a s m e a s u r e d a s 2 .8 6 p m i n 2 0 p s p u ls e d u r a tio n , 10 p s s ta n d b y tim e a n d 5 a m p c u rre n t.

•

T h e h ig h e s t s u rfa c e r o u g h n e s s v a lu e w a s f o u n d to b e 10 p s p u ls e d u r a tio n , 10 p s w a it tim e a n d 4 .0 7 p m a t 15 a m p e r e s c u rre n t.

•

I t h a s b e e n o b s e r v e d th a t m u ltip le p a r a m e te r s

•

If

a f fe c t s u rfa c e ro u g h n e s s v a lu e s . no

p r e s s u r iz e d

w a te r

is

k e p t b e tw e e n

th e

m a te ria l a n d th e e le c tr o d e d u r in g th e te s t, i t is d e te r m in e d

th a t

th e

e ro d ed

m a te ria l

and

th e

e le c tr o d e p a r ts m o v e th e h e a d w h ic h p e r fo r m s th e p lu n g e

by

s h o r t- c ir c u itin g

th e

d e v ic e .

If

no

p r e s s u r iz e d w a t e r is k e p t b e tw e e n th e m a te ria l a n d th e e le c tr o d e d u r in g th e te s t, it is d e te r m in e d th a t th e e r o d e d m a te ria l a n d th e e le c tr o d e p a r ts m o v e th e h e a d w h i c h p e r f o r m s th e p lu n g e b y s h o r tc ir c u itin g th e d e v ic e .

REFERENCES1234567890 [1 ] Qogun, C., Kocaba§ B., and Ozgedik A., Experimental and theoretical investigation of workpiece surface profiles in electrical discharge machining (EDM). Gazi Universty. Journal of Faculty of Engineering and Architecture, 2004. 19 (1). [2] Avlar, E., Experimental investigation on technological feasibility study of spherical tool electrodes in edm rough machining: Machining of rectangular pockets. Selcuk University, 2006, Institute of Science and Technology. [3] Gulcan, O., Processing with electro-erosion inpure water . Engineer &the Machinery Magazine, 2014(648). [4] Lee, J., et al., Modern manufacturing, mechanical engineering handbook. Boca Raton, 1999. [5] Ho, K. and Newman S., State of the art electrical discharge machining (EDM). International Journal of Machine Tools and Manufacture, 2003. 43(13): p. 1287-1300. [6 ] Huang, F., Influence ofkerosene and distilledwater as dielectrics on the electric discharge machining characteristics of Ti-6A1-4V. Journal of Materials Processing Tech., 1999. 1(87): p. 107-111. [7] Bayramoglu, M., Electrical discharge machines and numerical control. Machine and Metal Technology, 1995. 45: p. 157-160. [8] Masuzawa, T. and Heuvelman C., A self-flushing method with sparkerosion machining. CIRP Annals-Manufacturing Technology, 1983. 32(1): p. 109-111. [9] Ozgedik, A. and Qogun C., An Investigation on the Effect of the Applied Machining Tank Vibrations on the Machining Performance in Electrical Discharge Machining. Electronic Journal of Machine Technologies, 2011. 8(3): p. 13-25. [10] Schumacher, B., About the role ofdebris in the gap during electrical discharge machining. CIRP Annals-Manufacturing Technology, 1990. 39(1): p. 197-199. [11] Ozgedik, A. and Cogun C., An experimental investigation of tool wear in electric discharge machining. The International Journal of Advanced Manufacturing Technology, 2006. 27(5): p. 488-500.

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