Jou nal o Manu ac u ing P ocesses 92 (2023) 500–520
A ailable online 15 Ma ch 2023
1526-6125/© 2023 The Au ho s. Published by Else ie L d on behal o The Socie y o Manu ac u ing Enginee s. This is an open access a icle unde he CC
BY-NC-ND license (h p://c ea i ecommons.o g/licenses/by-nc-nd/4.0/).
No el d ill geome ies o d y d illing o s ainless s eel
Luk´
aˇ
s Pelik´
an
a
,
*
, Michal Slaný
a
, Ondˇ
ej S ´
anský
a
, Libo Be ´
anek
a
, Zdeˇ
nek Pi muc
a
,
Lenka ˇ
Cepo ´
a
b
, ˇ
S ˇ
ep´
anka D oˇ
´
aˇ
cko ´
a
c
a
Depa men o Machining, P ocess planning and Me ology, Facul y o Mechanical Enginee ing, Czech Technical Uni e si y in P ague, 166 00 P ague, Czech Republic
b
Depa men o Machining and Assembly, Facul y o Mechanical Enginee ing, VSB-Technical Uni e si y o Os a a, 708 33 Os a a, Czech Republic
c
Facul y o Mechanical Enginee ing, TU Libe ec, S uden ska 2, 461 17 Libe ec 1, Czech Republic
ARTICLE INFO
Keywo ds:
D y machining
17-4 PH s eel
S ainless s eel
D ill geome y
D y d illing
Tool op imiza ion
ABSTRACT
One comple ely new geome y and wo modi ied chip b eake geome ies we e designed o inc ease he s abili y
and eliabili y o he s ainless s eel d y d illing p ocess. Expe imen s we e pe o med and he esul s o indi idual
ools we e compa ed wi h a con en ional solid ca bide wis d ill Güh ing Ra io wi h a diame e o 5 mm. A
ma ix o h ee eed a es (0,03–0,07 mm/ e ) and h ee cu ing speeds (20–30 m/min) was designed o he
cu ing condi ions. P ecipi a ion-ha denable s ainless s eel 17-4 PH was chosen as a wo kpiece. Du ing he
expe imen , he alues o h us o ce, spindle o que, empe a u e o he ool, su ace oughness, chips
mo phology and chips di ision we e eco ded and compa ed wi h he e e ence ool.
The esul s showed ha compa ed o he e e ence ool A, he ool C - a mul ipoin d ill wi h g oo es h ough
he cu ing edge achie e app oxima ely 4 % lowe alues o h us o ce and 10–15 % lowe alues o spindle
o que. Tool D wi h a s ep d ill geome y achie e app oxima ely 17 % lowe alues o h us o ce and 10–15 %
lowe alues o spindle o que and he e is no chip clogging in he lu e wi h C and D geome ies. This e ec is
con i med by he ac he spindle o que basically does no inc ease wi h he inc easing dep h o d illing. Tool B –
new designed geome y achie e app oxima ely 15 % lowe alues o h us o ce and simila spindle o que
alues as he e e ence d ill A. Tool empe a u e is a e y impo an ac o when d y d illing. Compa ed o he
e e ence d ill A, i was possible o achie e he ool empe a u e educ ion o 20 % wi h he new geome y B, as
well as wi h he mul ipoin d ill C educ ion by 26 % and wi h he s ep d ill D educ ion app oxima ely by 30 %.
All he modi ied d ills also achie ed a educ ion in he su ace oughness o he d illed holes. By 17 %, 35 % and
48 % lowe su ace oughness Ra was achie ed wi h d ills B, C and D. Chip mo phology was signi ican ly
di e en o he es ed d ills. Con en ional wis d ills A and B gene a ed helical sho chips. While C and D wis
d ills wi h di ided cu ing edges gene a ed ibbon sna led chips. Thanks o he educ ion o cu ing o ces and
empe a u e, i is possible o s ably ope a e he d illing p ocess wi h a highe cu ing speed and eed a e, which
leads o an inc ease in he e iciency and eliabili y o he machining p ocess.
1. In oduc ion
Ac oss p oduc ion ields, d illing echnology is one o he mos
impo an me al cu ing ope a ions. Mo e han ¾ o me al cu ing p o-
cesses in ol e d illing ope a ions [1] [2]. The mos widesp ead use o
his echnology is in indus ies such as au omo i e and ae ospace. The e
is also a high consump ion o cu ing luids in hese a eas, whe he hey
a e emulsions o oils. Wo ldwide, his amoun s o se e al million li e s
o cu ing luids pe yea . This consump ion ep esen s hund eds o
billions o USD in o al global machining cos s, aking in o accoun only
he wo ld's la ges economies [3].
The use o cu ing luids in indus y also has a nega i e impac on he
en i onmen and on he heal h o machine ope a o s. The high wa e
consump ion associa ed wi h he use o cu ing luids is nowadays a
undamen al p oblem in many egions, because he ecycling and
disposal o used cu ing luids is an ene ge ically and en i onmen ally
demanding p ocess [4]. In ela ion o machine ool ope a o s, ae osol
inhala ion and skin con ac pose he g ea es isk [5] [6]. Fo hese
easons, i is inc easingly p e e able o conside machining wi h mini-
mum coolan (MQL), o comple ely d y machining [7].
Howe e , he use o cu ing luids has a signi ican e ec on he
cu ing p ocess. App op ia ely applied cu ing luids has a posi i e
* Co esponding au ho .
E-mail add ess: [email p o ec ed] (L. Pelik´
an).
Con en s lis s a ailable a ScienceDi ec
Jou nal o Manu ac u ing P ocesses
jou nal homepage: www.else ie .com/loca e/manp o
h ps://doi.o g/10.1016/j.jmap o.2023.03.006
Recei ed 30 Decembe 2022; Recei ed in e ised o m 3 Ma ch 2023; Accep ed 4 Ma ch 2023
Jou nal o Manu ac u ing P ocesses 92 (2023) 500–520
501
impac on lub ica ion and hus educing ic ion, educing empe a u e,
imp o ing chip e acua ion, educing a o ma ion o a build-up edge and
imp o ing he opog aphy o he machined su ace [8]. Especially o
he me al d illing p ocess, he in luence o he cu ing luid is c ucial. I
signi ican ly helps o emo e chips om he cu ing zone, s abilizes he
cu ing p ocess and helps o achie e be e quali y o d illed holes in
e ms o su ace quali y, dimensions and geome ic speci ica ions [9]
[10]. When conside ing d illing wi hou cu ing luids (d y machining),
all o he pa ame e s a ec ing he d illing p ocess a e essen ial. We a e
mainly alking abou ool geome y, wo kpiece ma e ial, cu ing con-
di ions, ool ma e ial and coa ing [11].
Tool geome y is one o he main ac o s ha can be di ec ly in lu-
ence o imp o e he d y machining p ocess pa ame e s [12] [13] [14].
This pape deals wi h he no el d ill designs o he needs o s ainless
s eel d y d illing. Ma ensi ic p ecipi a ion-ha denable s ainless s eel
17-4PH was chosen as he wo kpiece ma e ial. I is high s eng h,
co osion esis an , good weldabili y, and oxida ion esis an s eel [15].
S ainless s eels in gene al a e ega ded as di icul - o-machine ma e ials
due o hei high endency o wo k ha den, hei oughness and ela-
i ely low he mal conduc i i y [16]. Fo hese easons, he designed
ools a e buil on he basis o solid ca bide d ills wi h coa ing. When d y
d illing, i is essen ial o o m a sui able chip, he shape o which will
allow i o lea e he cu ing zone smoo hly. The goal is o design a d ill
geome y ha will gene a e chips capable o lea ing he cu ing zone
quickly and wi h minimal esis ance. The d ill will gene a e low cu ing
o ces and empe a u e concu en ly.
Fo wis d ills, cu ing o ces and chip o ma ion a e signi ican ly
in luenced by he geome y o he chisel edge. Ve y low o ze o cu ing
speed is achie ed in his a ea. The chisel edge can con ibu e >55 % o
he o al h us o ce, while he chisel edge occupies abou 20 % o he
cu ing edge o al leng h, depending on he speci ic geome y [17] [18].
Chip o ma ion and i s esul ing shape a e also signi ican ly in luenced
by he geome y o he chisel edge o web hinning [19] [20]. Published
chisel edge modi ica ions a e implemen ed on HSS d ills and we
machining is conside ed. The di e en p ope ies o cemen ed ca bide
and he di e en coe icien o ic ion du ing d y machining mus be
conside ed. The i s modi ied design (d ill A) ope a es p ima ily wi h
he chisel edge modi ica ions. The modi ica ions aim o inc ease he chip
ensile s ess in he a ea o he ansi ion be ween he chisel edge and he
main cu ing edge and he eby achie e a highe le el o chip cu l.
Ano he e ec o he modi ica ions lies in he enla gemen o he a ea o
he chips o ma ion and e acua ion om he chisel edge. The e ec o
enla ging he chisel edge a ea on he o ma ion and e acua ion o chips
is no well desc ibed, unlike he e ec o enla ging he helix on he
e acua ion o al eady o med chips [21].
Ano he op ion o di iding chips in o smalle elemen s is d ills wi h
a spli cu ing edge. This is ad an ageously used in s ack d illing. By
changing he cou se o he h us o ce and dis ibu ing he cu ing
o ces o e mul iple cu ing edges, s ep d ills help o educe delamina-
ion [22] [23]. The dis ance be ween he i s and second s eps o d ill is
usually a ew millime e s in s ack d illing applica ions. The s ep d ill
concep is used by some manu ac u e s (Milwaukee, MSTM) o s eel
d illing applica ions as well. Howe e , he indi idual s eps a e only a
ew en hs o a millime e apa . This concep is no commonly used in
combina ion wi h s ainless s eel d illing, o e en d y d illing. Ne e -
heless, his concep was chosen as ano he modi ied d ill design (D ill
D) because i s abili y o b eak he chip in o smalle elemen s can be
bene icial.
G oo es o pins on he ace o he d ill a e o en used as ano he
a ian s o chip b eake s. A educ ion in cu ing o ces o 5–9 % has been
achie ed when machining aluminum alloy using a pin chip b eake
[24]. Wi h he g oo e ype o chip b eake , a educ ion o cu ing o ces
in he d illing dep h o 3D and mo e has been achie ed when machining
low ca bon s eel. A he same ime, ool li e was inc eased due o he
educ ion o chip e acua ion o ces [25]. Bo h examples o chip b eake s
we e es ed using cu ing luid. Some manu ac u e s (Isca , MSTM) use
g oo es in he cu ing edges ha lead h ough he lank. This concep
educes he s uc u al s eng h o he cu ing wedge compa ed o chip
b eake s on he ool ace. On he o he hand, i b ings lowe empe a-
u es in he cu . Due o his ad an age, g oo ed chip b eake design is
being conside ed o use in bone d illing [26].
In o de o op imize he d illing p ocess, e alua ion c i e ia mus be
de e mined. Th us o ce and spindle o que a e widely used o e alua e
he d illing p ocess and ha e a di ec impac on hole quali y, ool wea
and p ocess s abili y. The empe a u e has a di ec e ec on ool wea
and chip o ma ion, as he plas ici y o he machined ma e ial inc eases,
he cu ing empe a u e inc eases [16] [27]. These pa ame e s a e
moni o ed in his s udy as key in o ma ion abou he machining p ocess
pe o mance.
Table 1
Mechanical p ope ies a e hea ea men .
UTS [MPa] 0,2 % YS [MPa] Rockwell ha dness [HRC]
1172 1138 38
Table 2
Chemical composi ion o 17-4 PH s eel.
Elemen C Mn P S Si C NI Cu Nb Fe
W % <0,07 <1 <0,04 <0,03 <1 15–17,5 3–5 3–5 0,15-0,45 emainde
Fig. 1. D ill geome y speci ica ions.
Table 3
D ill angles.
D ill
α
β γ δ R
A, C, D 78◦35◦30◦1◦1.3
B 100◦45◦30◦6◦1.3
L. Pelik´
an e al.
Jou nal o Manu ac u ing P ocesses 92 (2023) 500–520
502
D y d illing is la gely sol ed o aluminum alloys [28] [29], i anium
alloys [7] [30], o composi es [31] [32]. D y d illing o s ainless s eels is
done a ely, due o hei di icul machinabili y. I expe imen s a e
ca ied ou , hen wi h AISI 304 s ainless s eel [33] [34]. F om he poin
o iew o ool op imiza ion, he published pape s mainly deal wi h
poin angle and compa ison o HSS ools [33] [35]. In e ms o long- e m
s abili y o he p ocess, howe e , HSS ools a e no able o wi hs and d y
d illing condi ions. While changing he poin angle does no b ing a
signi ican change in he o ma ion o chips - one o he essen ial ac o s
o d y d illing.
17-4 PH s eel is a e y p omising ma e ial. Wi h s anda d ools o
s eel d illing, i is e y di icul o implemen d y machining, because
he e a e di icul ies wi h he s abili y o he p ocess, o sudden
des uc ion o he ool due o high cu ing o ces and high empe a u es.
The new geome y is designed o imp o e hese p ope ies, while
keeping he classic wis d ill concep . This concep gene a es helical
chips ha a e ad an ageous due o packing and he e is no isk o
winding on he ool. The o he wo designs a e an al e na i e o he
exis ing d ills wi h chip b eake . They a e designed wi h cu ing edge
s i ness in mind, as his concep is no commonly used o d ill s ainless
Fig. 2. D ill A.
Fig. 3. D ill B.
L. Pelik´
an e al.
Jou nal o Manu ac u ing P ocesses 92 (2023) 500–520
503
s eel. This app oach b ings a signi ican educ ion in cu ing o ces and
empe a u e. Howe e , he disad an age is he con inuous chip, which
can wind up on he ool and is space-consuming.
2. Ma e ials and me hods
2.1. Wo kpiece
The expe imen al s udy was ca ied ou on ma ensi ic p ecipi a ion
ha dened s ainless s eel 17-4 PH. This ma e ial can be ound unde he
s anda d SAT Type 630, AISI 630 o DIN 1.4542. Specimen dimensions
we e 88 mm (leng h) ×72 mm (wid h) ×15 mm ( hickness).
The op su ace has been machined o gua an ee i s la ness. The
wo kpiece was hea ea ed in he H 1025 condi ion be o e machining.
This condi ion including hea ing o 551 ◦C, holding on empe a u e o
4 h and ai cooling below 32 ◦C. Used hea ea men leads o ollowing
specimen mechanical p ope ies [36] (Tables 1-2):
2.2. Tools
Fo his expe imen , he Güh ing Ra io 2473 d ill wi h a diame e o
5 mm was chosen as he de aul ool. This ool was used wi hou
Fig. 4. – D ill A (le ) and D ill B ( igh ) web hinning compa ison.
Fig. 5. D ill C.
Fig. 6. D ill C geome y speci ica ions.
L. Pelik´
an e al.
Jou nal o Manu ac u ing P ocesses 92 (2023) 500–520
504
modi ica ions as a e e ence ool unde he designa ion D ill A. Subse-
quen ly, 3 a ian s wi h modi ied geome y we e designed. The de aul
ool was always he Güh ing Ra io 2473, on which he modi ica ions
desc ibed below we e made.
Fo he pu poses o his expe imen , he ollowing igu e shows he
de ini ion o se e al ool angles ha we e adop ed (Fig. 1). Thei alues
a e p esen ed in he Table 3.
2.2.1. D ill A
I is a monoli hic ca bide d ill wi h a diame e o 5 mm, a leng h o
3D wi h an poin angle o 140◦and a helix angle o 30◦. Spli poin
design is used o web hinning. The ool is equipped wi h a coa ing wi h
he ade name nanoFIRE, which is based on TiN-TiAlN (Fig. 2).
Fig. 7. D ill D.
Fig. 8. D ill D geome y speci ica ions.
Table 4
Lis o expe imen al cu ing condi ions.
Condi ions 1 2 3 4 5 6 7 8 9
Cu ing speed [m/min] 20 20 20 25 25 25 30 30 30
Feed a e [mm/ e ] 0.03 0.05 0.07 0.03 0.05 0.07 0.03 0.05 0.07
L. Pelik´
an e al.

Jou nal o Manu ac u ing P ocesses 92 (2023) 500–520
505
2.2.2. D ill B
This ool ea u es a newly designed geome y. I has been modi ied
especially in he chisel edge a ea. Web hinning has been modi ied o
c ea e mo e space o chip o ma ion om he hinning edge. This
caused he chisel edge o hin. The co e igidi y o he d ill is he e o e
compensa ed by a smalle inclina ion o he elie (β) (Fig. 3).
The ollowing igu es show a compa ison o d ill A and B in he chisel
edge a ea. The ed line indica es he cu ing edge o d ill A. In he pho o
o d ill B, he enla ged a ea o he o ma ion and e acua ion o chips
om he cen e o he ool is highligh ed in yellow (Fig. 4).
2.2.3. D ill C
D ill C has he same geome y as d ill A. In addi ion, i was equipped
wi h a chip b eake in he o m o g oo es on bo h cu ing edges o he
pu pose o di iding he chip in o smalle elemen s. The g oo es on bo h
cu ing edges a e in di e en posi ions o compensa e o each o he and
no lea e a cu ing edge shape a he bo om o he hole (Fig. 5).
The igu e below shows a de ail o he g o es design in he cu ing
edges o he d ill (Fig. 6).
2.2.4. D ill D
D ill D is a s ep d ill. The i s s ep has he same geome y as he
e e ence d ill A. The second s ep is o se by 0.2 mm and has a poin
angle o 140◦. The cu ing edge is di ided in o wo sepa a e pa s ( wo
s eps) and hus sepa a e smalle chips should be c ea ed (Fig. 7).
The igu e below shows a de ail o he s ep d ill geome y (Fig. 8).
2.3. Expe imen al se up
The expe imen was pe o med on a e ical milling machine HAAS
VF2 wi h maximum spindle speed o 8100 pm and powe ou pu 22.4
kW. The ool was clamped o he spindle using a o a y dynamome e
Kis le RCD 9163. I is a 4-componen dynamome e o measu ing o
cu ing o ces in x, y and z di ec ion and o ques on he o a ing ool
spindle. Th us o ce and spindle o que we e eco ded using he
dynamome e . A p o ec i e plexiglass was emo ed on he side o he
milling machine and a FLIR T640 he mal came a was secu ely ixed
ou side he machining a ea. The empe a u e was measu ed h oughou
he machining ime. The peek empe a u e was always eached when
he ool was wi hd awn ou o he hole. This poin was always chosen as
Fig. 9. Expe imen al se up.
L. Pelik´
an e al.
Jou nal o Manu ac u ing P ocesses 92 (2023) 500–520
506
he eco ded alue.
The su ace oughness o he d illed holes was measu ed using a
Ma Su LD 120 machine om he Mah company. Measu emen was
pe o med using p obe a m LD B 4–10-27,144 a 5 di e en loca ions.
The measu ed da a we e p ocessed using Ma Win so wa e. To e alua e
he su ace oughness, he basic wa eleng h λc 0,8 mm was chosen and
hus he o al measu ed leng h Ln 4 mm. The su ace scanning speed was
0,5 mm/s.
A ull ac o ial design wi h 3 cu ing speeds a 3 eed a es was used
o his expe imen . Each expe imen al condi ion was epea ed ou
imes o a e aged alues. Howe e , he aim o he expe imen is no o
e alua e he dependence o he obse ed alues on he cu ing condi-
ions, bu o compa e di e en ly modi ied ools. These 9 combina ions o
cu ing condi ions we e chosen because each ool can achie e he bes
pe o mance unde di e en cu ing condi ions. To selec cu ing con-
di ions, a p elimina y es was pe o med wi h e e ence d ill A. Highe
cu ing speeds and highe eed a es we e es ed un il he d ill ailed. The
ange o cu ing condi ions was chosen in a sa e window so ha he e is
no dange o sudden des uc ion o he d ill (Table 4).
Since he expe imen ocuses on he esea ch o d ills sui able o d y
d illing, o cou se no coolan was used. Blind holes we e d illed o a
dep h o 13 mm in he 15 mm hickness wo kpiece (Fig. 9).
3. Resul s and discussion
The measu ed alues we e eco ds o a combina ion o h ee cu ing
speeds and h ee eed a es. F om he esul s o h us o ce, spindle
o que, and empe a u e, a colo map was c ea ed demons a ing he
magni ude o hese alues. The colo anges a e always iden ical o a
speci ic da a se , so ha i is possible o easily compa e indi idual ools
wi h each o he .
3.1. Th us o ce
Th us o ce and spindle o que we e measu ed using he o a y
dynamome e . In he ollowing igu e, ypical h us o ce cu es o
indi idual ools can be seen. These o que cu es we e measu ed unde
condi ions o V
c
=25 m/s and =0,05 mm/ e (Fig. 10).
Du ing he d illing o he en i e dep h o he hole, an almos cons an
cou se o h us o ce was obse ed in all expe imen al uns. The median
alue om he en i e d illed dep h was used o p ocess he measu ed
da a.
Fig. 11 shows he dependence o h us o ce on cu ing condi ions
o indi idual ools. I can be s a ed ha o all ools he e is an inc ease
in h us o ce wi h inc easing eed a e. The e ec o he cu ing speed is
p esen ed only by a sligh inc ease in he h us o ce when he cu ing
speed inc eases.
D ill A achie es he highes alues o h us o ce in he en i e ange
o es ed cu ing condi ions. The g aph shows ha he e is a signi ican
inc ease in h us o ce wi h inc easing eed a e compa ed o d ill B and
D. D ill C also shows a signi ican inc ease in h us o ce wi h inc easing
eed a e. The absolu e alues o he eed a e a e app oxima ely 20 N
lowe compa ed o d ill A.
D ill B and D showed a lowe inc ease in h us o ce depending on
he inc easing eed a e. Absolu e h us o ce alues a e also lowe . A a
eed a e o 0.07 mm/ e , bo h he B and D d ills achie e a 100 N lowe
h us o ce compa ed o he e e ence d ill A (Figs. 12-15).
3.2. Spindle o que
Likewise h us o ce, spindle o que was measu ed using a o a y
dynamome e . In he ollowing igu e, ypical spindle o que cu es o
indi idual ools can be seen. These o que cu es we e measu ed unde
condi ions o V
c
=25 m/s and =0,05 mm/ e (Fig. 16).
A simila cou se can be obse ed in he en i e ange o measu ed
cu ing condi ions. The e alua ion o he spindle o que ook place on
he linea egion on he op o he d illed hole. A signi ican inc ease in
o que wi h inc easing hole dep h can be seen o ools A and B. This
phenomenon is caused by he clogging o chips in he d ill lu e [37]. Fo
d ill B, his e ec is sligh ly less signi ican . Thanks o he modi ied
geome y o he cu ing edge, i gene a es smalle chips and he e is a
be e di ision o chips and hus easie e acua ion om he cu ing zone.
Fo d ills C and D, he o que cu e is essen ially linea du ing d illing o
he en i e dep h o he hole. This is due o he o ma ion o a comple ely
di e en shape o chips (see chap e 3.5). Long con inuous chips had no
endency o clogging in he lu e and we e smoo hly e acua ed om he
cu ing zone.
Fo compa ison, he g aph in Fig. 17 shows he o que a di e en
eed a es a V
c
=25 m/min o indi idual d ills. The hick ligh e line
shows he alue o he linea egion o he o que when d illing a a
shallow dep h. The hin da k line shows he maximum o que ha was
achie ed when d illing a he la ges d illed dep h o 13 mm. I can be
seen om he g aph ha o d ills A and B he e is a signi ican inc ease
Fig. 10. Th us o ce eco d - d ill bi s compa ison.
L. Pelik´
an e al.
Jou nal o Manu ac u ing P ocesses 92 (2023) 500–520
507
Fig. 11. Th us o ce - d ill bi s compa ison.
20
25
30
300
345
390
435
480
525
570
615
660
0.03
0.05
0.07
Cu ng speed [m/min]
Th us o ce [N]
Feed a e [mm/ e ]
D ill A - Th us o ce
300-345 345-390 390-435 435-480 480-525 525-570 570-615 615-660
Fig. 12. Th us o ce - d ill bi A.
L. Pelik´
an e al.
Jou nal o Manu ac u ing P ocesses 92 (2023) 500–520
508
in o que a a g ea e d illing dep h. Fo d ills C and D, he inc ease in
o que is minimal. Howe e , he alue o he maximum o que is only
indica i e, as signi ican oscilla ions o he eco ded alue occu . Fo
u he e alua ion, alues om he linea ange a e used (Fig. 18).
When compa ing he linea ange o spindle o que, i can obse ed
ha e e ence d ill A achie es he highes alues. D ill B achie es
app oxima ely 0.1 Nm lowe alues in he en i e ange o cu ing con-
di ions. Fo d ills C and D, he alues a e e en 0.05–0.1 Nm lowe han
in he case o d ill B (Figs. 19-22).
F om he pe spec i e o he dependence o spindle o que on cu ing
condi ions, an inc ease in o que wi h inc easing eed a e can be seen
o all d ills. I is a na i e e ec , as a la ge dep h o ma e ial is being cu .
Fo d ills A, B and C, a sligh inc ease in o que can also be obse ed wi h
inc easing cu ing speed. In gene al, he opposi e end can be obse ed
in machining, as he empe a u e in he cu inc eases wi h inc easing
cu ing speed and he mechanical p ope ies o he machined ma e ial
dec ease. In his case, wo phenomena may occu :
In he case o d y d illing wi h inc easing cu ing speed, he e is an
inc ease in ic ion no only be ween he ool and he wo kpiece in a
cu ing zone, bu also be ween he chips and he lu e and he wall o he
d illed hole [16].
S ainless s eels ha e high oughness and low he mal conduc i i y
and easily s ick o he ake ace as he empe a u e inc eases [38].
Fig. 13. Th us o ce - d ill bi B.
20
25
30
300
345
390
435
480
525
570
615
660
0.03
0.05
0.07
Cung speed [m/min]
Th us o ce [N]
Feed a e
[mm/ e ]
D ill C - Th us o ce
300-345 345-390 390-435 435-480 480-525 525-570 570-615 615-660
Fig. 14. Th us o ce - d ill bi C.
L. Pelik´
an e al.
Jou nal o Manu ac u ing P ocesses 92 (2023) 500–520
515
signi ican ly lowe compa ed o con en ional A and B wis d ills.
D ill D achie ed app ox. 48 % lowe su ace oughness Ra compa ed
o he e e ence d ill A. Unde condi ions o V
c
=25 m/min and =0.05
mm/ e , i was 1.12
μ
m. As wi h ool C, ool D also bene i s om he
o ma ion o con inuous chips ha quickly lea e he cu ing zone.
Compa ed o d ill C, d ill D shows a lowe su ace oughness Ra unde
mos cu ing condi ions. This is ela ed, among o he hings, o he lowe
cu ing o ces and lowe o que achie ed by he d ill D.
3.5. Chip o ma ion
Chip shape is one o he mos impo an ac o o su icien d illing
p ocess. The d illing p ocess can only be s able and eliable i he e is
smoo h chip e acua ion [41]. I depends on he shape o he lu e,
ic ion coe icien be ween chips, d ill and wall o he hole, bu abo e
all on he shape o he chip [42]. Mac oscopic e alua ion o he chips
was ca ied ou using an op ical mic oscope (Fig. 31).
Fig. 26. Max empe a u e - d ill bi B.
Fig. 27. Max empe a u e - d ill bi C.
L. Pelik´
an e al.

Jou nal o Manu ac u ing P ocesses 92 (2023) 500–520
516
Acco ding o ISO 3685, we can e alua e he shape o he chips as
ollows:
D ill A gene a ed mos ly helical sho chips. Only a he lowes eed
a e o 0.3 mm/ e does he ul ima e ensile s eng h in he chip mo e
a ound he c i ical alue. The c i ical alue mus exceed he ul ima e
ensile s eng h o he machined ma e ial unde he ac ual condi ions o
chip sepa a ion o occu . A =0.3 mm/ e , some chips a e helical sho
because he c i ical alue has been exceeded and some chips a e helical
sna led because he c i ical alue has no been exceeded.
D ill B gene a ed helical sho chips. These chips a e di ided in o
indi idual cones. A a eed a e o 0.3 mm/ e , he e is a g ea e
de o ma ion o he chips be o e hei sepa a ion. Because o his, he
chips a e longe . As he eed a e inc eased, he s i ness o he chips
inc eased and his leads o easie b eakage [43].
D ill C gene a ed ibbon sna led chips. The e a e g oo es on he
cu ing edge o he ool ha a e deepe han he dep h o he eed a e.
Ne e heless, he e was no spli ing o chips in o na ow sepa a e ib-
bons. Indi idual chips a e he wid h o he en i e cu ing edge (Fig. 32).
On he chip pa e n we can see 2 s ipes om he g oo es in he
cu ing edge. In hese a eas, s ong plas ic de o ma ion occu ed, and
because o his, he chip emains con inuous ac oss he en i e wid h o
he cu ing edge.
D ill D gene a ed ibbon sna led chips. E en hough he e a e wo
s eps o he d ill and hus he e a e 2 sepa a e cu ing edges on each side,
he chips a e wide and con inuous (Fig. 33).
The e is no no iceable ansi ion be ween he indi idual cu ing
Fig. 28. Max empe a u e - d ill bi D.
Fig. 29. Roughness measu emen loca ions in he hole.
L. Pelik´
an e al.
Jou nal o Manu ac u ing P ocesses 92 (2023) 500–520
517
0.00
0.50
1.00
1.50
2.00
2.50
3.00
3.50
20 25 30
Ra [μm]
Cung speed [m/min]
Su ace oughness Ra
= 0.05 mm/ e
D ill A D ill B D ill C D ill D
0.00
0.50
1.00
1.50
2.00
2.50
3.00
3.50
0.03 0.05 0.07
Ra [μm]
Feed a e [mm/ e ]
Su ace oughness Ra
Vc= 25 m/min
D ill A D ill B D ill C D ill D
Fig. 30. Su ace oughness Ra - d ill bi s compa ison.
Fig. 31. Mac oscopic chips mo phology.
L. Pelik´
an e al.
Jou nal o Manu ac u ing P ocesses 92 (2023) 500–520
518
edges on he de ail o he chip. These chips a e signi ican ly wide han
hose gene a ed by d ill C. The edges o he chips a e mo e agged and
he chips a e di ided in o sho e elemen s. All his indica es ha he e is
e en mo e plas ic de o ma ion han in he chips gene a ed by d ill C.
3.6. Chip di ision
Chip di ision, oge he wi h i s shape, is a e y impo an ac o o
smoo h and eliable chip e acua ion. The pieces pe weigh a io
me hod was used. In his case, he numbe o chips elemen s pe 1 g o
chips is indica ed. Mo e chips pe 1 g means smalle chips elemen s.
Di ided small chips p e en ool b eaking, because hey enable hei
smoo h e acua ion and he e o e a smoo h d illing p ocess. A he same
ime, i imp o es he quali y o he holes and inc eases he ool li e [44].
Howe e , i depends no only on he size o he chips, bu on he com-
bina ion o size and shape o he chips [45] (Fig. 34).
F om he g aph, we can obse e ha he smalles chip elemen s a e
gene a ed by d ill B. Due o he modi ied geome y, especially in he
a ea o web hinning, ine chip di ision occu s unde mos condi ions
compa ed o he e e ence d ill A.
D ill C gene a ed almos exclusi ely long ibbon chips. The e o e, we
can obse e he smalles numbe o chip elemen s pe 1 g.
D ill D gene a ed signi ican ly sho e ibbon chips ha we e
accompanied by sho elemen s. Thanks o his, he numbe o chips
eached highe alues compa ed o he d ill C.
4. Conclusion
In his s udy, ool geome y modi ica ions we e analyzed when d y
d illing o p ecipi a ion ha denable s ainless s eel 17-4PH. Th ee ge-
ome ies sui able o d y d illing we e designed and compa ed wi h a
con en ional wis d ill design. D ill A is he e e ence ool – a con-
en ional monoli hic ca bide wis d ill. D ill B has a modi ied geome y
specially adap ed o d y d illing. The o he wo d ills a e equipped wi h
chip b eake s, which a e no no mally used o d y d illing. The e o e,
he chip b eake s ha e been modi ied wi h ega d o he s i ness o he
cu ing edge. D ill C is equipped wi h g oo es in he cu ing edges. D ill
D is a s ep d ill wi h wo s eps.
The ools we e es ed unde a ious cu ing condi ions in a combi-
na ion o 3 cu ing speeds and 3 eed a es. The e ec on h us o ce,
spindle o que, ool empe a u e, su ace oughness and chip di ision
du ing d illing numbe o holes was analyzed. The ollowing conclusions
may be d awn om his wo k:
1. Th us o ce inc eases wi h inc easing eed a e, while cu ing speed
has e y small e ec . The p og ess o he h us o ce depending on
he d illing dep h was nea ly cons an . D ills B and D achie ed
app oxima ely 100 N lowe compa ed o he e e ence ool.
2. Spindle o que inc eases wi h inc easing eed a e and cu ing speed.
Wi h inc easing d illing dep h inc eased o que up o +200 % o
d ills A and B a a maximum d illing dep h o 13 mm. This is caused
by he clogging o chips in he d ill lu e. While d ills C and D show
only a small inc ease (10–20 %) in o que depending on he d illing
dep h, because hei chip shapes allowed smoo h e acua ion om
he cu ing zone.
3. The empe a u e o he ool inc eases wi h inc easing cu ing speed
and eed a e. The highes empe a u e alues we e eached by
e e ence d ill A, up o 300 ◦C a e being pulled ou o he hole.
Modi ied d ills gene a ed an a e age o 20 %, espec i ely 26 %
lowe empe a u es and up o 40 ◦C, espec i ely 50 ◦C lowe em-
pe a u e a he highes cu ing condi ions o d ill B, espec i ely
d ill C. d ill D has a e y di e en empe a u e p o ile depending on
he cu ing condi ions. Unde he highes cu ing condi ions, i ea-
ches up o 70 ◦C less han d ill A.
4. The su ace oughness dec eases wi h inc easing cu ing speed, while
inc easing wi h inc easing eed a e. The e e ence d ill eached
su ace oughness om Ra 1.2
μ
m o Ra 3.4
μ
m, depending on he
cu ing condi ions. Modi ied d ills achie ed an a e age o 17 %, 35
%, espec i ely 48 % lowe oughness Ra o d ill B, C, espec i ely D
compa ed o he e e ence d ill.
5. The shape o he chips a ied signi ican ly be ween indi idual ools.
D ills A and B gene a ed helical sho chips. While d ills C and D
gene a ed ibbon sna led chips. Chips gene a ed by he d ill B we e
di ided in o he smalles elemen s - up o 200 single elemen s pe 1 g
Fig. 32. Chip de ail - D ill C.
Fig. 33. Chip de ail - D ill D.
L. Pelik´
an e al.
Jou nal o Manu ac u ing P ocesses 92 (2023) 500–520
519
o chips. While d ill A eached 180 elemen s pe 1 g. D ill D gene a e
>80 elemen s pe 1 g and d ill C only 60 elemen s pe 1 g.
As a esul , i can be s a ed he modi ica ions o he d ills led o a
educ ion in cu ing o ces and empe a u es and, hanks o his, o an
inc ease in he s abili y o he cu ing p ocess, which enables long- e m
ope a ion unde highe cu ing condi ions. This was achie ed du ing d y
machining o ma e ial 17-4 PH, which is no mally conside ed di icul o
machine e en wi h he use o cu ing luid [46].
Tes s o he ool li e and long e m s abili y o he p ocess should be
he subjec o u he in es iga ion as well as machinabili y o he
wo kpiece ma e ial unde highe cu ing condi ions.
Decla a ion o compe ing in e es
The au ho s decla e ha hey ha e no known compe ing inancial
in e es s o pe sonal ela ionships ha could ha e appea ed o in luence
he wo k epo ed in his pape .
Re e ences
[1] Günay M, Me al T. Modelling and mul i esponse op imiza ion o minimizing bu
heigh , h us o ce and su ace oughness in d illing o e i ic s ainless s eel 2020;
45. h ps://doi.o g/10.1007/s12046-020-01490-3.
[2] Am an M, Salmah S, Hussein N, Izamshah R, Hadzley M, Si a aos, Kasim M,
Sulaiman M. E ec s o machine pa ame e s on su ace oughness using esponse
su ace me hod in d illing p ocess. P ocedia Eng 2013;68:24–9. h ps://doi.o g/
10.1016/j.p oeng.2013.12.142.
[3] As akho V. Ecological machining: nea -d y machining. Machining 2008:195–223.
h ps://doi.o g/10.1007/978-1-84800-213-5_7.
[4] Gaj ani K, Ram D, Sanka M, Dixi U, Su in P, Kailas S. Machining o ha dened AISI
H-13 s eel using minimum quan i y eco- iendly cu ing luid. In: In e na ional
jou nal o addi i e and sub ac i e ma e ials manu ac u ing. 1 ed. Inde Science;
2018. p. 240–56. h ps://doi.o g/10.1504/IJASMM.2017.089925.
[5] Gup a K. A e iew on g een machining echniques. In: P ocedia manu ac u ing. 51
ed. Else ie ; 2020. p. 1730–6. h ps://doi.o g/10.1016/j.p om g.2020.10.241.
[6] S eeji h P, Ngoi B. D y machining – machining o he u u e, he in e na ional.
J Ma e P ocess Technol 2000:289–93. h ps://doi.o g/10.1016/S0924-0136(00)
00445-3.
[7] Can e o J, Ta dío M, Can eli J, Ma cos M, Migu´
elez M. D y d illing o alloy
Ti–6Al–4V. In J Mach Tool Manu 2005;45:1246–55. h ps://doi.o g/10.1016/j.
ijmach ools.2005.01.010.
[8] Shok ani A, Dhokia V, Newman S. En i onmen ally conscious machining o
di icul - o-machine ma e ials wi h ega d o cu ing luids. In J Mach Tool Manu
2012;57:83–101. h ps://doi.o g/10.1016/j.ijmach ools.2012.02.002.
[9] Ba˘
gci E, Ozcelik B. In es iga ion o he e ec o d illing condi ions on he wis d ill
empe a u e du ing s ep-by-s ep and con inuous d y d illing. Ma e Des 2006;27:
446–54. h ps://doi.o g/10.1016/j.ma des.2004.11.018.
[10] She e H, Sohani M. E ec o p ocess pa ame e s on hole diame e accu acy in high
p essu e h ough coolan peck d illing using aguchi echnique. In J Ma e Fo m
Mach P ocess 2018;5:12–31. h ps://doi.o g/10.4018/IJMFMP.2018010102.
[11] Kane iya N, Sha ma G. Expe imen al e alua ion and op imiza ion o d y d illing
pa ame e s o AISI304 aus eni ic s ainless s eel using di e en wis d ills. In: 5 h
in e na ional & 26 h all India manu ac u ing echnology, design and esea ch
con e ence. 543 ed. 2014. p. 1–7.
[12] Kı ak T, Sam as
¸ G, Çiçek A. Taguchi me hod based op imisa ion o d illing
pa ame e s in d illing o AISI 316 s eel wi h PVD monolaye and mul ilaye coa ed
HSS d ills. Measu emen 2012;45:1547–57. h ps://doi.o g/10.1016/j.
measu emen .2012.02.022.
[13] Gemi L, Mo ka uk S, K¨
oklü U, Gemi D. An expe imen al s udy on he e ec s o
a ious d ill ypes on d illing pe o mance o GFRP composi e pipes and damage
o ma ion. Compos Pa B Eng 2019;172:186–94. h ps://doi.o g/10.1016/j.
composi esb.2019.05.023.
[14] Koklu U, Mo ka uk S, U ekin L. E ec s o he d ill lu e numbe on d illing o a
cas ed AZ91 magnesium alloy. Ma e Tes 2019;61:260–6. h ps://doi.o g/
10.3139/120.111315.
[15] Sun Y, Zhong Y, Wang L. The in e ac ion be ween
ε
-coppe and disloca ion in a
high coppe 17–4PH s eel. Ma e Sci Eng A 2019;756:319–27. h ps://doi.o g/
10.1016/j.msea.2019.03.092.
[16] Kamdani K, Hamsah A, Ra ai N, Rahim M, Wong C, Chong Y. S udy o cu ing o ce
and su ace oughness on d illing s ainless s eel 316L unde a ious coolan
condi ion. Key Eng Ma e 2018;791:116–22. h ps://doi.o g/10.4028/www.
scien i ic.ne /KEM.791.116.
[17] Paul A, Kapoo S, DeVo R. A chisel edge model o a bi a y d ill poin geome y.
J Manu Sci Eng 2005;127:23–32. h ps://doi.o g/10.1115/1.1826076.
[18] Claudin C, Poulachon G, Lambe in M. Co ela ion be ween d ill geome y and
mechanical o ces in MQL condi ions. Mach Sci Technol 2008;12:133–44. h ps://
doi.o g/10.1080/10910340801918275.
Fig. 34. Chip o ma ion - d ill bi s compa ison.
L. Pelik´
an e al.
Jou nal o Manu ac u ing P ocesses 92 (2023) 500–520
520
[19] Paul A, Kapoo S, DeVo R. Chisel edge and cu ing lip shape op imiza ion o
imp o ed wis d ill poin design. In J Mach Tool Manu 2005;45:421–31. h ps://
doi.o g/10.1016/j.ijmach ools.2004.09.010.
[20] Ke F, Ni J, S ephenson D. Con inuous chip o ma ion in d illing. In J Mach Tool
Manu 2005;45:1652–8. h ps://doi.o g/10.1016/j.ijmach ools.2005.03.011.
[21] Abele E, Fuja a M. Simula ion-based wis d ill design and geome y op imiza ion.
CIRP Ann 2010;59:145–50. h ps://doi.o g/10.1016/j.ci p.2010.03.063.
[22] Qiu X, Li P, Li C, Niu Q, Chen A, Ouyang P, Ko T. S udy on chisel edge d illing
beha io and s ep d ill s uc u e on delamina ion in d illing CFRP. Compos S uc
2018;203:404–13. h ps://doi.o g/10.1016/j.comps uc .2018.07.007.
[23] Fei o N, Díaz-´
Al a ez J, L´
opez-Puen e J, Miguelez M. Expe imen al and nume ical
analysis o s ep d ill bi pe o mance when d illing wo en CFRPs. Compos S uc
2018;184:1147–55. h ps://doi.o g/10.1016/j.comps uc .2017.10.061.
[24] Sahu S, Bu ak Ozdoganla O, DeVo R, Kapoo S. E ec o g oo e- ype chip
b eake s on wis d ill pe o mance. In J Mach Tool Manu 2003;43:617–27.
h ps://doi.o g/10.1016/S0890-6955(02)00303-6.
[25] Na h C, Ku ess T. Obs uc ion- ype chip b eake s o con ollable chips and
imp o ed cooling/lub ica ion du ing d illing – a easibili y s udy. P ocedia Manu
2016;5:375–85. h ps://doi.o g/10.1016/j.p om g.2016.08.032.
[26] Akhba M, Sulong A. Su gical d ill bi design and he momechanical damage in
bone d illing: a e iew. Ann Biomed Eng 2021;49:29–56. h ps://doi.o g/10.1007/
s10439-020-02600-2.
[27] Ju ko J, Panda A. Simula ion o accompanying phenomena in he cu ing zone
du ing d illing o s ainless s eels. In: 2010 3 d in e na ional con e ence on
ad anced compu e heo y and enginee ing(ICACTE). IEEE; 2010. h ps://doi.o g/
10.1109/ICACTE.2010.5579026. pp. V1-239-V1-243.
[28] Habib N, Sha i A, Hussain A, Aami M, Giasin K, Pimeno D, Ali U. Analysis o
hole quali y and chips o ma ion in he d y d illing p ocess o Al7075-T6. Me als
2021;11. h ps://doi.o g/10.3390/me 11060891.
[29] Dasch J, Ang C, Wong C, Cheng Y, Weine A, Le L, Konca E. A compa ison o i e
ca ego ies o ca bon-based ool coa ings o d y d illing o aluminum. Su Coa
Technol 2006;200:2970–7. h ps://doi.o g/10.1016/j.su coa .2005.04.025.
[30] P asanna J, Ka unamoo hy L, Venka Raman M, P ashan h S, Raj Cho dia D.
Op imiza ion o p ocess pa ame e s o small hole d y d illing in Ti–6Al–4V using
Taguchi and g ey ela ional analysis. Measu emen 2014;48:346–54. h ps://doi.
o g/10.1016/j.measu emen .2013.11.020.
[31] Ameu M, Habak M, Kenane M, Aouici H, Cheikh M. Machinabili y analysis o d y
d illing o ca bon/epoxy composi es: cases o exi delamina ion and cylind ici y
e o . In J Ad Manu Technol 2017;88:2557–71. h ps://doi.o g/10.1007/
s00170-016-8967-8.
[32] Rawa S, A ia H. Cha ac e iza ion o he d y high speed d illing p ocess o wo en
composi es using machinabili y maps app oach. CIRP Ann 2009;58:105–8. h ps://
doi.o g/10.1016/j.ci p.2009.03.100.
[33] Çaydas
¸ U, Hasçalık A, Buy oz ¨
O, Mey eci A. Pe o mance e alua ion o di e en
wis d ills in d y d illing o AISI 304 aus eni ic s ainless s eel. Ma e Manu P ocess
2011;26:951–60. h ps://doi.o g/10.1080/10426914.2010.520790.
[34] Wang T, Zhang J, Li Y, Gao F, Zhang G. Sel -lub ica ing TiN/MoN and TiAlN/MoN
nano-mul ilaye coa ings o d illing o aus eni ic s ainless s eel. Ce am In 2019;
45:24248–53. h ps://doi.o g/10.1016/j.ce amin .2019.08.136.
[35] Vas JS, Fe nandes A, D’Souza A, Rai A, Quad os JD. Analysis o empe a u e
changes du ing d y d illing o aus eni ic s ainless s eels on wis d ills ha ing
di e en poin angles. J Mech Eng Au om 2016:121–5. h ps://doi.o g/10.5923/c.
jmea.201601.23. Scien i ic & Academic Publishing.
[36] 17-4 PH S ainless s eel ma e ial equi alen and p ope ies, Aes ei on s eels LLP.
h ps://www.aes ei on.com/17-4-ph-s ainless-s eel.pd . [Accessed 7 Oc obe
2022].
[37] Han C, Zhang D, Luo M, Wu B. Chip e acua ion o ce modelling o deep hole
d illing wi h wis d ills. In J Ad Manu Technol 2018;98:3091–103. h ps://doi.
o g/10.1007/s00170-018-2488-6.
[38] Chen W, Liu X. S udy on he a ious coa ed wis d ills o s ainless s eels d illing.
J Ma e P ocess Technol 2000;99:226–30. h ps://doi.o g/10.1016/S0924-0136
(99)00428-8.
[39] Himme C, U˘
gu K. D illing o AZ31 magnesium alloy unde d y and c yogenic
condi ions. J Ma e Manu 2022;2022:7–13. h ps://doi.o g/10.5281/
zenodo.7107296.
[40] Sul an A, Sha i S, Ku niawan D. E ec o machining pa ame e s on ool Wea and
hole quali y o AISI 316L s ainless s eel in con en ional d illing. P ocedia Manu
2015;2:202–7. h ps://doi.o g/10.1016/j.p om g.2015.07.035.
[41] K¨
oklü U, Koça O, Mo ka uk S, Giasin K, Aye ¨
O. In luence o ex usion pa ame e s
on d illing machinabili y o AZ31 magnesium alloy. P oc Ins Mech Eng E: J
P ocess Mech Eng 2022;236:2082–94. h ps://doi.o g/10.1177/
09544089221080820.
[42] Çiçek A, Kı ak T, Uygu I, Ekici E, Tu gu Y. Pe o mance o c yogenically ea ed
M35 HSS d ills in d illing o aus eni ic s ainless s eels. In J Ad Manu Technol
2012;60:65–73. h ps://doi.o g/10.1007/s00170-011-3616-8.
[43] Koklu U, Kayhanla H. An expe imen al in es iga ion on machinabili y o AZ31B
magnesium alloy unde d y and dipped c yogenic app oaches. J Ma e Eng Pe o m
2022;31:1285–96. h ps://doi.o g/10.1007/s11665-021-06264-4.
[44] Habib N, Sha i A, Hussain A, Aami M, Giasin K, Pimeno D, Ali U. Analysis o
hole quali y and chips o ma ion in he d y d illing p ocess o Al7075-T6. Me als
2021;11. h ps://doi.o g/10.3390/me 11060891.
[45] Zhang P, Chu i N, Pei Z, T eadwell C. Mechanical d illing p ocesses o i anium
alloys: a li e a u e e iew. Mach Sci Technol 2008;12:417–44. h ps://doi.o g/
10.1080/10910340802519379.
[46] Si aiah P, Chak adha D. Machinabili y s udies on 17–4 PH s ainless s eel unde
c yogenic cooling en i onmen . Ma e Manu P ocess 2017;32:1775–88. h ps://
doi.o g/10.1080/10426914.2017.1339317.
L. Pelik´
an e al.