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SUBJECT TITLE:
MODERN MANUFACTURINGTECHNOLOGIES
CREDIT HOURS: 02
TEXT BOOK:
MANUFACTURING PROCESSESFOR ENGG MATERIALS BY SEROPE
KALPAKJIAN
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ASSESSMENT INFO
• One Hour Class Tests wtg: 20% x 02 = 40%
• Quizzes wtg: 3% x 5 = 15%
• Assignents wtg: 5% x 1 = 5%
• !inal wtg: 40 % x 1 = 40%
• "iniu Atten#an$e e&uire#: '5%
• Course "aterial: 1( )e$ture *li#es2( e+eren$e ,oo-s
3( .nternet
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"anu+a$turing /ro$ess
*tarting aterial /ro$esse# art
*$ra an# waste
" a $ 1 i n
e r 2
T o o l i n g / o w
e r
) a 3 o r
Manufacturing is the transformation of materials into items of greater value by means of one or more processing and/or assemblyoperations.
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at is "anu+a$turing
"anu+a$turing is te organize# a$ti6it #e6ote# to
te trans+oration o+ raw aterials into ar-etale
goo#s
/riar .n#ustr *e$on#ar .n#ustr
Agri$ulture7 !orestr7 "ining7
"ineral 8xtra$tion et$ "anu+a$turing .n#ustries
A anu+a$turing sste usuall elos a series o+ 6alue9a##ing
anu+a$turing ro$esses to $on6ert raw aterials into ore use+ul
+or an# e6entuall into +inise# ro#u$ts
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"anu+a$turing .n#ustries
• Two ,roa#er Categories w(r(t ro#u$t
Consuer goo#s
Caital goo#s
• "ore tan 450 #i++erent tes o+ in#ustries
a e $lassi+ie# wi$ a e groue#
in 20
*ee tale in next sli#e ((
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Indust! P"du#t C$t%&"!
Aerosa$e Caital
*iuil#ing Caital
"a$ine9Tool anu+a$turing Caital
Autooti6es Consuer ; Caital
8le$troni$s Consuer ; Caital
Couter "anu+a$turing Consuer ; Caital
Couter *o+tware Consuer ; Caital
"etal7 $oal7 oil Consuer ; Caital
Cei$al .n#ustr Consuer ; Caital
Textile .n#ustr Consuer
)eater .n#ustr Consuer
Cloting an# +ootwear Consuer
To a-ing Consuer
oo# an# tier ro#u$tion Consuer
/aer7 rinting ; ulising Consuer
,uil#ing "aterials Consuer ; Catial
!urniture .n#ustr Consuer
!oo# ro$essing Consuer
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"anu+a$turing /ro$esses
Classi+i$ation
• , ro$ess te$nolog
• , ro#u$t
• , ro#u$tion &uantit• , le6el o+ autoation
• An oter wa
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M$t%'$( R%)"*$( P"#%ss%s
+M$#,'n'n&-
"a$ining re+ers to $utting oerations tat are ase# on
te reo6al o+ aterial +ro an originall roug9sae#
wor-ie$e7 +or exale 6ia $asting or +orging troug
ower #ri6en a$ines(
"a$ining is te ro$ess o+ reo6ing unwante#
aterial +ro a wor-ie$e in te +or o+ $is( .+ te
wor-ie$e is a etal7 te ro$ess is o+ten $alle# etal
$utting or etal reo6al(
"a$ining is a anu+a$turing ro$ess in wi$ a sar
$utting tool is use# to $ut awa aterial to lea6e te
#esire# art sae(
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.ortan$e o+ "a$ining
• ariet o+ wor- aterials
•ariet o+ art saes an# geoetri$+eatures
• oo# sur+a$e +inises
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M$t%'$( R%)"*$( P"#%ss%s
+M$#,'n'n&-
A complex process and difficult to analyze. Why?
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M$t%'$( R%)"*$( P"#%ss%s
+M$#,'n'n&-
Tere are se6en asi$ $i +oration ro$esses:
./ Tun'n&
2( *awing3( >rin#ing
4( "illing
5( *aing
D( ,roa$ing
'(
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M$t%'$( R%)"*$( P"#%ss%s
+M$#,'n'n&-
Tun'n& is a machining process in which a single-point tool removes
material from the sur+a$e o+ a rotating $lin#ri$al wor-ie$eF te tool is
+e# linearl in a #ire$tion arallel to te axis o+ rotation7 as illustrate# in
!igure(
!or all etal $utting ro$esses7 it is ne$essar to #istinguis
etween speed 7 feed an# depth of cut
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M$t%'$( R%)"*$( P"#%ss%s
+M$#,'n'n&-
Cutting araeters
*ee# 6B is te riar $utting otion7 wi$ relates te 6elo$it o+ te
rotating wor-ie$e wit rese$t to te stationar $utting tool(
6 = G
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M$t%'$( R%)"*$( P"#%ss%s
+M$#,'n'n&-
Cutting *ee# in Turning
Cutting see# is te see# at te outsi#e e#ge o+ te art as it is rotating( Tis is
also -nown as sur+a$e see#(
Ta-e two weels7 one weel wi$ is tree +eet in #iaeter an# te oter weel
wi$ is one +oot in #iaeter7 roll ea$ weel one $olete turn !igureB(
,'#, ,%%( '(( t$*%( ;$t,%7 ,!7
Te larger weel will tra6el +arter e$ause it as a larger $ir$u+eren$e an# as
ore sur+a$e area( Cutting see#s wor- on te sae rin$ile
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M$t%'$( R%)"*$( P"#%ss%s
+M$#,'n'n&-
Cutting *ee# in Turning
Te /" setting #een#s on te $utting see# an# te #iaeter o+ te art( Te
/" setting will $ange wit te #iaeter o+ te art( As te #iaeter o+ te art
gets saller7 te /" ust in$rease to aintain te re$oen#e# sur+a$e
see#(
Tin- o+ te art as a weel an# te $utting see# as a #istan$e( A larger weel
artB will nee# to turn +ewer re6olutions er inute to $o6er te sae #istan$e in
te sae aount o+ tie tan a saller weel artB( Tere+ore7 to aintain te
re$oen#e# $utting see#7 larger #iaeter arts ust e run at slower see#s
tan a saller #iaeter art(
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M$t%'$( R%)"*$( P"#%ss%s
+M$#,'n'n&-
Cutting *ee# in Turning
Cutting see#s #een# riaril on te te o+ aterial ou are $utting
an# te -in# o+ $utting tool ou are using(
Te ar#ness o+ te wor- aterial as a great #eal to #o wit tere$oen#e# $utting see#(
Te ar#er te wor- aterial7 te slower te $utting see# an# 6i$e9
6ersa(
Te ar#er te $utting tool aterial7 te +aster te $utting see# an#6i$e96ersa(
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M$t%'$( R%)"*$( P"#%ss%s
+M$#,'n'n&-
Cutting *ee# in Turning
E6$)(%
A $ut is to e a#e wit a ig9see# steel H**B tool on a 29in$ #iaeter
ie$e o+ 101I steel wit a rinnel ar#ness o+ 200( Cal$ulate te /" setting to
er+or tis $ut(
Cutting *ee# = 100 +B
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M$t%'$( R%)"*$( P"#%ss%s
+M$#,'n'n&-
Cutting araeters
Te #et o+ $ut #B is te #istan$e te tool is lunge# into te wor-ie$e(
Te turning oeration re#u$es te #iaeter o+ te wor- +ro its original
#iaeter $o to a final diameter $f # as determined !y the depth of cut d%
nits: in7 7
# =
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M$t%'$( R%)"*$( P"#%ss%s
+M$#,'n'n&-
Cutting araeters
!ee# +B is te #istan$e tool o6es towar#s wor-ie$e or te aount o+
aterial reo6e# er re6olution o+ te tool o6er te wor-ie$e(
Te +ee# in turning is generall exresse# in re6( Tis +ee# $an e$on6erte# to a linear tra6el rate in in te +orula
+ r = ?+
+ r = +ee# rate inB+ = +ee# re6B 9 set anuall
? = otational *in#le see#
re6inB
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M$t%'$( R%)"*$( P"#%ss%s
+M$#,'n'n&-
Cutting araeters
"a$ining tie $an e $al$ulate# using te +ollowing e&uation:
) = wor-art lengt B
T = "a$ining tie inB
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M$t%'$( R%)"*$( P"#%ss%s
+M$#,'n'n&-
"aterial eo6al ate "B: .t is te aount o+ aterial reo6e# te$utting tool in unit tie(
nits: in3in7 3in
"= 6B +B #B
Te units o+ L+L are expressed
simply as mm &in'# in effect
neglecting the rotationalcharacter of turning(
Cutting araeters
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M$t%'$( R%)"*$( P"#%ss%s
+M$#,'n'n&-
!ee# in "illingB
+ =+ tn?
"illing7 a ultile toot ro$ess as
two +ee#s: Te #istan$e tat tewor-ie$e +ee#s into ea$ toot as
it rotates7 $alle# te ;%%d %
t""t,7 + t7 tootB an# te rate at
wi$ te tale translates ast te
rotating tool7 $alle# te t$5(% ;%%d7
+ 7 in
ere n= no( o+ teet+ t
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Ot,"&"n$( Cutt'n& M"d%(
, #e+inition7 ortogonal $utting uses a we#ge9sae# tool in wi$ te
$utting e#ge is eren#i$ular to te #ire$tion o+ $utting see#(
As te tool is +or$e# into te aterial7 te $i is +ore# sear
#e+oration along a lane $alle# shear plane, wi$ is oriente# at s,%$
$n&(% M
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P')$! $nd S%#"nd$! S,%$ >"n%s
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Ot,"&"n$( Cutt'n& M"d%(Te tool in ortogonal $utting as onl two eleents o+ geoetr: 1B ra-e
angle an# 2B $learan$e angle( A $3% $n&(% 's t,% $n&(% 5%t%%n t,%(%$d'n& %d&% "; $ #utt'n& t""( $nd %%nd'#u($ t" t,% su;$#% 5%'n&
#ut/ Te ra-e angle LNL #eterines te #ire$tion tat te $i +lows as it is
+ore# +ro te wor-artF an# te $learan$e angle ME ro6i#es sall
$learan$e etween te tool +lan- an# te newl generate# wor- sur+a$e(
?
4ϕ
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F"#%s 'n M%t$( Cutt'n&
*e6eral +or$es $an e #e+ine# relati6e to te ortogonal $utting o#el(
!igure A: !or$es in etal $utting: aB +or$es a$ting on te $i in ortogonal
$utting7 an# B +or$es a$ting on te tool tat $an e )%$su%d(
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F"#%s 'n M%t$( Cutt'n&
Te friction force ( is te +or$e resisting te +low o+ te $i along
te ra-e +a$e o+ te tool( Te normal force to friction ) iseren#i$ular to te +ri$tion +or$e( Tese two $oonents $an e
use# to #e+ine te $oe++i$ient o+ +ri$tion etween te tool an# te
$i:
Te +ri$tion +or$e an# its noral +or$e $an e a##e# 6e$toriall to
+or a resultant +or$e7 R.
R is oriente# at an angle P7$alle# te +ri$tion angle(
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F"#%s 'n M%t$( Cutt'n&
.n a##ition to te tool +or$es a$ting on te $i7 tere are two +or$e
$oonents alie# te wor-ie$e on te $i: sear +or$e an#
noral +or$e to sear(
Te shear force ( s# is te +or$e tat $auses sear #e+oration to
o$$ur in te sear lane( Te normal force to shear ( n* is
eren#i$ular to te sear +or$e(
,ase# on te sear +or$e7 te sear stress tat a$ts along te sear
lane etween te wor- an# te $i is #e+ine# as:
were As =area o+ te sear lane( Tis sear lane area $an e
$al$ulate# as:
Te sear stress reresents te le6el o+ stress re&uire# to er+or
te a$ining oeration(
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F"#%s 'n M%t$( Cutt'n&
!our +or$e $oonents (# )# (s# an# (n $annot e #ire$tl
easure# in a a$ining oeration7 e$ause te #ire$tions in wi$
te are alie# 6ar wit #i++erent tool geoetries an# $utting
$on#itions(
Howe6er7 it is ossile +or te $utting tool to e instruente# using a
+or$e easuring #e6i$e $alle# a #naoeter7 so tat two a##itional
+or$e $oonents a$ting against te tool $an e #ire$tl easure#i(e(
Te cutting force ( c # is in te #ire$tion o+ $utting7 te sae #ire$tion
as te $utting see# 67 an# te thrust force ( t is eren#i$ular to
te $utting +or$e an# is asso$iate# wit te $i ti$-ness e+ore te$ut t o.
Te rese$ti6e #ire$tions o+ tese +or$es are -nown7 so te +or$e
trans#u$ers in te #naoeter $an e aligne# a$$or#ingl
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F"#%s 'n M%t$( Cutt'n&
8&uations $an e #eri6e# to relate te +our +or$e $oonents tat
$annot e easure# to te two +or$es tat $an e easure#(
sing te +or$e #iagra in !igure ,7 te +ollowing trigonoetri$
relationsis $an e #eri6e#:
.+ $utting +or$e an# trust +or$e are
-nown7 tese +our e&uations $an e
use# to $al$ulate estiates o+ sear
+or$e7 +ri$tion +or$e7 an# noral +or$e
to sear an# +ri$tion(
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Te "er$ant 8&uation
Assu)t'"n:
Te sear strengt o+ te wor- aterial is a $onstant7
una++e$te# strain rate7 teerature an# oter +a$tors(
Tere+ore te e&uation +or is an aroxiate relation
rater tan an a$$urate ateati$al e&uation(
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Te "er$ant 8&uation
Te sear lane angle $an e in$rease# :
1B.n$reasing te ra-e angle NB
2B
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Te "er$ant 8&uationA greater shear plane angle results in lower cuttingenergy , lower power requirements, and lower cuttingtemperature.
A i ti + T i
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Aroxiation o+ Turning
Ortogonal Cutting
!igure: Aroxiation o+ turning te ortogonal o#el: aB turningF an#
B te $orreson#ing ortogonal $utting(
A i ti + T i
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Aroxiation o+ Turning
Ortogonal Cutting
Con6ersion -e: turning oeration 6s( ortogonal $utting(
C tt' F ' T '
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Cutt'n& F"#%s 'n Tun'n&
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Types of Chips in Machining
• Chip formation affects the surface finish, cutting forces,
temperature, tool life and dimensional tolerance.
• Understanding the chip formation during the machining
process for the specific materials is useful to determine the
machining speeds, feed rates and depth of cuts for efficient
machining and increase tool life.
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Types of Chips in Machining
During the machining process, four basic types of chips
are formed:
1. Discontinuous
2. Continuous
3. Continuous with uilt!up "dge
#. $errated chip formation
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Types of Chips in Machining
Discontinuous chips: %hen relati&ely brittle materials 'e.g. cast iron( are
machined at low cutting speeds, the chips often form into separate
segments 'sometimes the segments are loosely attached(. )his tends to
impart an irregular te*ture to the machined surface. +igh tool!chip friction
and large depth of cut promote the formation of this chip type
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Types of Chips in Machining
Continuous chip: %hen ductile wor materials are cut at high speeds and
relati&ely small feeds and depth of cut, long continuous chips are formed.
- good surface finish results when this type of chip is formed. - sharp
cutting edge of the tool and low tool chip friction encourage the formation
of continuous chips. ong, continuous chips can cause problems with
regard to chip disposal and /or tangling about the tool. )o sol&e these
problems, turning tools are often e0uipped with chip breaers.
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Types of Chips in Machining
Continuous chip with built-up edge: %hen machining ductile materials at low tomedium cutting speeds, friction between tool and chip tends to cause portion of the
wor material to adhere to the rae face of the tool near the cutting edge. )his
formation is called a built up edge 'U"(. )he formation of U" is cyclical it forms
and grows, then becomes unstable and breas off. uch of the detached U" is
carried away with the chip, some times taing portions of the tool rae face with it,
which reduces the life of the cutting tool. ortions of the detached U" that are notcarried off with the chip become imbedded in the newly created wor surface, causing
the surface to become rough.
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Types of Chips in Machining
Serrated or Shear localized chips: )hese chips are semi continuous inthe sense that they possess a saw!tooth appearance that is produced by a
cyclical chip formation of alternating high shear strain followed by low
shear strain. )his type of chip is formed during machining of metals
such as titanium alloys, nicel!base super!alloys, and austenitic stainless
steels at higher cutting speeds. +owe&er, the phenomenon is also found
with more common wor metals 'e.g. steels( when they are cut at high
speeds.
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Cutting Temperature
O+ te total energ $onsue# in a$ining7 nearl all o+ it aroxiatelKI%B is $on6erte# into eat( Tis eat $an $ause teeratures to e 6er
ig at te tool9$i inter+a$e9o6er D00 RC is not unusual( Te reaining
energ aout 2%B is retaine# as elasti$ energ in te $i
Cutting teeratures are iortant
e$ause ig teeratures 1B
re#u$e tool li+e 2B ro#u$e $is
tat ose sa+et azar#s to te
a$ine oerator an# 3B $an
$ause ina$$ura$ies in wor-art
#iensions #ue to teral
exansion o+ te wor- aterial(
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Cutting Temperature
Tere are 6arious was to easure re#i$t teerature:
1(!8 Analsis
2(Teral .aging Caera
3(/roeters
4(Tero$oules
an# an ore S
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Temperature at the Tool-Chip
InterfaceC""3=s ;")u($
4.3334.# ('U Vt
T C K ρ
∆ =
T=ean teerature rise at te tool $i inter+a$e7 C !BF =se$i+i$
energ in te oeration( U3 in9lin3B = $utting see# s insB
t=un#e+ore# $i ti$-ness inBF V$=6oluetri$ se$i+i$ eat o+ te
wor- aterial U39C in9lin39!BF W= teral #i++usi6it o+ te wor-
aterial7 2s in2sB
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High Speed MachiningHig9see# a$ining H*"B eans using $utting see#s tat are
signi+i$antl iger tan tose use# in $on6entional a$iningoerations(
*oe exales o+ $utting see# 6alues +or $on6entional an# H*"
are resente# in Tale 1
Tale 1: Coarison o+ $utting see#s use# in $on6entional 6ersus ig9see#
a$ining +or sele$te# wor- aterials
i S i i
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High Speed Machining
Oter #e+initions o+ H*" a6e een #e6eloe# to #eal wit te
wi#e 6ariet o+ wor- aterials an# tool aterials use# in
a$ining(
Te $t'" "; ,"s%"% t" )$6')u) s'nd(% s%%d7 or
r ratio( Con6entional a$ine tools usuall a6e a igerr ratio tan a$ines e&uie# +or ig9see# a$ining(
Te #i6i#ing line etween $on6entional a$ining an# H*" is
aroun# 0(005 r(
H'&, s%%d )$#,'n'n& @ 0/00 ,1)
C"n*%nt'"n$( )$#,'n'n& 0/00 ,1)
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High Speed Machining
Ad*$nt$&%s:
!aster ro#u$tion rates*orter lea# tiese#u$e# $osts greater nuer o+ ro#u$tsB
.ro6e# art &ualit
D's$d*$nt$&%s:
.nitial $aital $osteair ; aintenan$e issues*-ille# laour ; rograer
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High Speed Machining
R%8u'%)%nts ;" HSM
1BHig9see# sin#les using se$ial earings #esigne# +or ig
r oeration
2BHig +ee# rate $aailit ti$all aroun# 50 in 2000
ininB
3BC?C otion $ontrols wit MMloo-9aea#EE +eatures tat allow te
$ontroller to see u$oing #ire$tional $anges an# to a-e
a#Xustents a$$or#ingl
4B,alan$e# $utting tools7 tool9ol#ers7 an# sin#les to iniize
6iration e++e$ts5BCoolant #eli6er sstes tat ro6i#e ressures an or#er o+
agnitu#e greater tan in $on6entional a$ining
DBCi $ontrol an# reo6al sstes to $oe wit te u$ larger
etal reo6al rates in H*"(
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High Speed Machining
HSM A('#$t'"ns
A%"s$#% $nd A'#$;t 'ndust'%s in wi$ long air+rae stru$tural
$oonents are a$ine# +ro large aluinu lo$-s( "u$ etal
reo6al is re&uire#7 ostl illing( Te resulting ie$es are
$ara$terize# tin walls an# large sur+a$e9to96olue ratios(
Te a$ining o+ aluinu ultile oerations to ro#u$e a 6ariet o+
$oonents +or in#ustries su$ as $ut")"t'*% #")ut% $nd )%d'#$((
"ultile $utting oerations ean an tool $anges as well as ig
a$$elerations an# #e$elerations o+ te tooling(
Anoter ali$ation +or H*" is in te d'% $nd )"(d 'ndust!7 wi$
+ari$ates $olex geoetries +ro ar# aterials( .n tis $ase7 ig9
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