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Preliminary report on the measurement of cutting-tool temperature Veenstra, P.C.; Bus, Chr.; Zweekhorst, E.T.W. Published: 01/01/1963 Document Version Publisher’s PDF, also known as Version of Record (includes final page, issue and volume numbers) Please check the document version of this publication: • A submitted manuscript is the author's version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website. • The final author version and the galley proof are versions of the publication after peer review. • The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication Citation for published version (APA): Veenstra, P. C., Bus, C., & Zweekhorst, E. T. W. (1963). Preliminary report on the measurement of cutting-tool temperature. (TH Eindhoven. Afd. Werktuigbouwkunde, Laboratorium voor mechanische technologie en werkplaatstechniek : WT rapporten; Vol. WT0072). Eindhoven: Technische Hogeschool Eindhoven. General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ? Take down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. Download date: 24. May. 2018

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Page 1: Preliminary report on the measurement of cutting-tool ... · PDF filePreliminary report on the measurement of cutting-tool temperature ... Preliminary report on the measurement of

Preliminary report on the measurement of cutting-tooltemperatureVeenstra, P.C.; Bus, Chr.; Zweekhorst, E.T.W.

Published: 01/01/1963

Document VersionPublisher’s PDF, also known as Version of Record (includes final page, issue and volume numbers)

Please check the document version of this publication:

• A submitted manuscript is the author's version of the article upon submission and before peer-review. There can be important differencesbetween the submitted version and the official published version of record. People interested in the research are advised to contact theauthor for the final version of the publication, or visit the DOI to the publisher's website.• The final author version and the galley proof are versions of the publication after peer review.• The final published version features the final layout of the paper including the volume, issue and page numbers.

Link to publication

Citation for published version (APA):Veenstra, P. C., Bus, C., & Zweekhorst, E. T. W. (1963). Preliminary report on the measurement of cutting-tooltemperature. (TH Eindhoven. Afd. Werktuigbouwkunde, Laboratorium voor mechanische technologie enwerkplaatstechniek : WT rapporten; Vol. WT0072). Eindhoven: Technische Hogeschool Eindhoven.

General rightsCopyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright ownersand it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.

• Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ?

Take down policyIf you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediatelyand investigate your claim.

Download date: 24. May. 2018

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laborotorhma VOOt ...-ehGt'lische tedmologie en werkplaotstechniek

. rGpport van d ... etie:Ma,chinlng

fltel: ~lt-RU7 .,. .... tu .....,.. ••• , .f .. ttlnc-tool

. ' • .,.rat.,...

auteur(s): P.rot .41'. p.e. " ... atra, Cllr .. h. III&_

II'. I.~.W. z..ekhorat.

' •• 1I_1oci.al Vrd.v •• elt,- liB4hov •• - HollaDd ..

sec:tieleider: Chr. Bus lug.

hoo9fi;aar:Prot .• Dr. P.C. Veell4ltra

prOgMS.

biz. 1 van 14 bl z.

rapport Dr. 0072

c:odering:

M 5,P 7 a 1

trefwoord:

cutting tool

temp.

Temp. meting

van draa i ... ,

beitel

ne.l.i.P.n

conferenoe

Cincinnati""

196:; U.S.A.

datum:

24-7-196:;

oantal biz. 14

r----~ geschikt voor I publicatie in:

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biz. 2 van 14 bIz.

o 1;' ..... 8' ,.,,,

'0

15

u

J

._~""'.f tUB hY.fiip.tifl1a lato the .. a8U ..... t.f tile t ....

pe"''''' ot fd' -ale P4Ite' o"ttu,toola ia to eoll.ct bforaa-. t1 .. t"&1"'4. a .~ .. U'-ya-t __ rature relatio ••

·--x~):'r~;.<:-~ • .' . - '

Fn_ the at pr._at kno •• aD4 "e.eloped' .. tbodatho ••• d .....

01'111.. ~,. Gott.el./I.rben has bee. OM_a.

!h ... th ••• ' ..... 4 .n ........... 'of radiatbuha ... e ROt be.n

•• ter •• 4u t. t,h. taot of tlle pe.t 41ttio.lt1. •• 1i1 olltaiaiac

a .. o11.a.le re1&ti08 lJ.t ••• a the ra41ation IMaaured aD4 the aufae.

t ..... rat.... .ft •• radiator.

Ike t .. I_ .... 1.ctrl0 llethodappeara to be a straight'orward one;

aad it 1 ..... acce.sible to physical anal7a1 ••

........ the ca11'bratloD. of t ... _aaur .... t can 11. p.rformed ia

a41ftct ad accurat •• &'3.

Eaowa 1. •• fM._that t.he Gott •• in-aethod u, to IlOW ~.a1. l •• da

,. ~Hbaol,. tar t .. 10. tip,. •• ot tile tPiperat-lIft'. of. o.tti .. . · ... 1 ...

Ia •• 1' op1a1oa tllU :La aaial1 cau_d b1 poor cal1.bntioa t.chaiq ..

aM perllap. '1 t ... e •• rlooki.ac o,a,'l ... e ther.eoapl •• h the

•• eurt.a. 81rc'tlit. fo .. tbi.s rea ......... 40ralll. amouat of .tte.tioa lIu b •• a giY ••

to the 4e .... lop •• 't ot a c&llbratloa .. t-up aft tile 41ec1pl1.o of

_"'1"188 taer."".lectrio teBaio •••

a) a. ..... ratur. elrtM.ia.4 with tbe Gott •• ia-.. tho4 ia U& a «004

~tioJl tbe aurace of the te.mperatur ••• f the 111' .... of.

Matact ", ...... tool. wen:p1.He an .. obi". on the 00 .. 1t10_ that

...... tile trau1tttta nsietu. •• ia tare.pout t ......... tile 18-

t..,-Ml "'.81._ce of tae '001 1. hip .ompue4 rita tlletra.a1.t.i •• ... at .....

Ia __ Ga._ ·t ...... aUtuu are DOt fulfill .. wtd.oh MU". t.lae

... nre4_emperatur.b\ing lo •• r ,tha,.."tlie p:~I,L"tempeJ;'a ture.

technisch. hog.school eindhoven

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rapport nr. 00?2 biz. 3 van 14blz.

r----------------------------------------------------------------------

o I- 'It) J1Il.alr.eulta or M&aUl"'''.''

51-

10 -

15 -

20 '--

2J I-

30 -

35 -

-40 ro-

.u I-

50 l-

lI!l. SaD.~ Coraaant - throw-away bits aumb.r: 194.4-1623 oarbid..· gra. S2 (I.S.O. - P20; U."S.A.. - C6)

P1P1." _t,riHt, st •• l c45 • 0.4~; 0.25%81; o,65%Ma; O,045~. x(p+s)

!Mitt" H.l, lathe A. I - DR 200, mod.ifi.d;-auJlib,r of rlYa:

o - 5OOQ/ata. coatiau"usly f •• ds: 0,0025-40.0 ..tr.Y, contiauously

laput pow.r: 60 kW max. motor: d.c., maga.tio amplifi.r control.

.pth .t cut, .. te.d, ..treY. cuttiag ap •• d aYerage t.mperatur. ~. .vat.a. 00

2 0,13 100 745 2 0.52 100 870 2 0,13 1.58 820 2 0,52 I 158 1005

6.56 0,10 200 870

6.56 0.69 aoo 1055

3. 1xDe£1 .. nt~ Tech!igu,s • . ) 'DIl • ... sur .... t of tem;2eratur. - .. !lle .xp.riments hav, b.en performed with a fixed toolg.o .. try

accorUq to the Sandrtk standard. toolho14er typ.: hR 174.2-2.52.5

a) ••• It rue angle • 0° lP) true rake angle • + ,0 .) ••• r.ll.! aftgl. 1III ,0 d) ai4. reli.f aa~ • • ,0 .) .ad. outtine .dg. aagl.

III 1" f) aid. cutti ... dg. angl, • 15' g) .'8. rad.1us • 3/64" ll) a. chi:e br.aker

tbe 'o.lAold.r haa b •• a modifi.d according to fig. 1 on. the pur-PO" of temperature .. asure.eat.

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rapport nr. 0072

work i.c.: ells

Rod C.t.5 inaul.t.ed. r ... "" ""lNlll.

-biz. 4 vaR 14 biz.

Tool hold.eY' ,., .. ulol.d. f ... o- la h

co.,t.o.c~. C.Ld. J'" ftC io-,,'----I--I----------t--4

l06~ ic el._c. .... t 5='ltS ''''.''' \.cat.c.ci .... ...

t.ool .... ld: ...

ri9 1 ~C.HEMATtC DIA 6RAM OF TOOLMOLDER MOOI.'E.O ON PUR.PO~£' 0.,. TE.MPJiRATURE MiAfJUREM1NT

fIae b1t 1. elaJiPed 111 tile .01'_1 way aIlt 18 toro •• at the ......

... '0 ... ela.tie .l .... t.... nt .f· the .orkpi.o. _t.rial.

WIle. '1M' , .. 1 1_ i. aoti •• the 81.' •• r.pr .... '. tae th • ..-..ple: .t .. 1-..... 14.-.t •• l. This theraoeo.pl. 1 •••• ,tl" ... __ a_. of the diff.l'.aoe in temper.tva b.t •••• tIMcnlltttas .... _4 , ..

real' ..... f the' b1t.

Th. elastio.le •• llt ooutaia. ia ita tip a Cr-Al th.e1"l108o.u .. hi ••

allow8 to _aaured1re.t11 tile t.aperat UN at t1M plaoe .f _oat .. , with the bit. A_._ in fig • .2 the th.r ...... l.ctric t.neio&8 of betll .t t_ ar ..... are feet iato tw. _rYO record..r ••

Oae .f tum (2) ... oo&+d.. the t • .,eratve of the rear .... t tile Ittt

tile ot •• r ... (1) reads the diff.rential voltage •• t ..... the eut-

iiDg .dge and the rear e.4 otthe bit. Typical recor4iaga are

shown •

werkplaat.tec:hnlek technlsch. hog.school eindhoven .",-.---~--~---.-----------------------.....,.------'

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rapport nr. 0072

0-

C 45 rod. tNSULATI.D 'ROM 6PINDLI.

chuck

5-

10 !-

15 i-

25i-

35-

40-

SOi-

r.: - -i-H::i:iii-Z = -II ~ II I 1 'I I

I I I I I I

Rot.ating ","ere:!. .. ¥' y conCoct:.

cold jU'nc:lio",",

, 1 I II 'I

" I, II I I I I I I 1 I I I I I I , I I I h I II I' I.L.L-------- ... <..:;; - - - - -~'

I'

I t

~"I.MATIC DIAGRAM O'F TEMPERATURE ME.A6URI.M!.NT

werkplaat.technie"

biz • .5 van 14 biz.

work piece C 46

ins'" l(l~ion

____ 1 ____ _ l

PC. Veenst.ra technische hogeschool eindhoven

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5

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25

rapport nr. 0072 . biz. 6 Waft 14 biz. 't\f~

, .

AslIWIiqaoal.1brati ... 0,,"_ 1. available rit. r08,peCt '0 tile

'leaperatve .a. tJa.,._-eleotrta t_DAn 1'01'. tld.. p.nlealar c ....

tdnatloa of cub1.. au _eel, it 1. poae1l1w to "'01'tl1u t ..

euttt.q ... g. t • .,e ... tv.f",scthe .. Ncorilaga,.,btaiD.ed.

!lie pr1clple ·of tIM .. tbo. ia .... 1 .. f1S. ~.

reor end tevnpera.i:..ure reo.d.in',3 of recoroLQ yo 2

coli bv-a ti O~ diog1"o

Sa ~ C 45

\ °C

culli~ edge teV"'t'\'pev-a.td .. .tV-<i':.

Tt6 . .Lt U~E 01= THE c.Al.leRATION CURVE TO DETERMINE· CUTT'N6-- £D4£ 'TE.M PE. RAT U RE

TlM re.4iq of re •• rior 2 1D °c 1. plotto' oa tho horiaoatal ad...

of t.he aalibratloa cliqraa. 'lho rea,tiac of recortler 1 1. plott"

1a t.e way abOWII. 18tor .. ot10a wit. ta. 0aU.1trat1oa evYe of t. AOriS.lltal 11 .. draw. froB ta. ".:1at 4.fi .... ill this W..., Oil tile

.ertlcal an. ".term11l88 the teap .... tvo·.f tile Cllt'US .... .

It 1. olear 1f q1l.it. • '-01" of .,..chJteao •• 1ator ... U ... 1 •••

ta the recor4iaga .f fig. I' ~l of th •• &a.... to re.ult 18 tile __

teaperatue a. the ".uibri1Ul of the cnattiag e'p18 r ...... Sa

a .ery abort time.

werlcplaatstMhnlek fectmische hogeschool eindhoven

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o

,

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15

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25

35

rapport nr. 0072 biz. 7 YIn 14 biz.

'fA1. all... to set a ",.ry goo.. aocuracy of the .. asuremeat .f til.

ayer... yalue accor4iag to the principl. ahown in fig. 5.

- --- ----- -~~-~-=-=-~-~-~-~-~-~-~--- ----- -- ---- col, byol::.ion

di0'9 yO \"Y'\ N ., .. .. , I.

t t --~- .... 'll " d • . ..

to. "

- --- - --1----;

fig 5

1 •

52- - C~5

... °C

co'leu lQ.tio~ or o.vev"QS Q. va-Lue

PR1NCIPLI OF ~YNCHR.ONOUS 'NTER~ECTtON6

'fll.up tile quality of SaDdvik oit8 ie of a very high standard

t.ere occur slight variations in the coapoeitioa which are ot

eoll.8 influ.ace on the thermo-.lectric properties.

'flUs forces to a correction for .,.ste .. tic errcrs in the .. asure­meate.

'fo this p.II.rpose three out ot the tour cutting edge. o't the Dit are

used tor normal measurementa.

The t.urth one ia applied for cutting uaing atandard conditions ot cutting ceometry and cutting speed.

r------------~-------------------------------------------~

werkplaotltechnl.k technische hogeschool eindhoven

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o

5

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25

30

35

50

~I • r

rapport nr. 0062 biz. 8 VIII 14 biz.

4,p171 .. tk. ..thod 4e8Orl\).d earlier aa4 ua1q • .t ........ oali­

brat.loll cur .... t.he meaaurelleat deli"ers a w.l1 4efl •• d ellttiag­

edge te.perature il1 ... 01"e4 with .. uakao •• sl.te .. t1eerror.

N.xt the cut is repeat.d with i ... tical standard. coudit~oa. but

now uuq a 80lid rod of sa .. terial carefull,.. groud. to. cuti

tool with the same geometr,.. .8 the bit.

Tlii. long rod allows a cooling of the far end eit ... r to roo.

te.perature or to the ice-point. Th. thermo-electric potential

corr.spond8 merel,.. to til. syst •• S2/c45 aatel is recorde4.

The same rod is u.ed in the calibration array as de.oribe4 later. Tbi.a calibration gives the staatdard calibratioll CU1'Y ...

III this VI.,.. it i8 p08.ible to deterlline the "true" te.,.rat.re

corresponding with the .tandard oonditione of cutting aJl4 the

method allow. the fixation of a point of reference aa ahow. ia

fig. 6 and the determaatioa of a ncorr~ctioD factor" for eacll

particular bit. stGPtda \"'01

fig 6

.... t. • " $. o " • "

ca'ibl"Qtion d.iQ..S ......... St - Clt5

absoL",l.. corVtU:t • .,r' ___ r~ ... bit~ /

/ /

/

/ /

/, ~

h-

reo"" GII""O l:.eVY'\ pevoQ.t.u ... Q~ Qrcnt .

tcw.p"..-QtYre of . cul:.b"" S edse

/'

yl I I

I

x

II< ·c

DETERMINATION OF C.ORREC.TION'FAC.TOR FOR /Itt. PA~T.eUL"R BIT

werkploatstechnlek technlache hogeschool eindhoven '-----------------,..-----------------_.-

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01-

5 .....

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15 !-

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30..,...

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roppert nr. 0072 blz.9 van 14 biz.

As easily will b. deri •• d from fiS. 6 the "correctton factor" of ,

a bit can'be defined as ~ t i.e. the value 1 obtained with that y

particular bit and using the standard calibration CUrTe should

b,eDltiplied with the factor.. to obtai. the real value "XU t

Y elef1n11lg with the same calibration curve the tltrue" temperature.

- In pract:i.c. it proves that the correction factor ahows 0.98 to'

1,12 as ultimate values.

Syachroaous intersections define very well the average apparent value of temperature while on the other banel a long run with the

standard rod define. the "true" temperature to a high grade of

accuracy, a.suming reliability of the calibration.

werkplClCltltechnlelc technische hogeschool eindhoven

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01-

II-

1Q I-

ts-

20-

25 -

101-

rapport nt. 007 2 bI Z. 10V811 14bJz.

.... TIM cfllibratioa of the slste. oarbide/steel.

Ae mentioned 'before the relia ... ili'7 of the GottweiD method depen4a

greatll" on the acouracl" of the calibration of the thermo-electric . I

Sl".tem.

Points of attentioa of major importance are:

1. the conditione of the calibration have to be comparable .ith

the conditione of cutting.

The contact surfaces between the workpiece material and the

carbide must be precision ground aad thouroughJ.7 018 .. ed in

order to provide a real intermetallic contact. Precautiou mUt

be taken to avoid oxydation of those .urtac •• , hence the cali­

Gratio., haa been pertormed in a protective gas atmosphere.

The specific mechanical load of the contact surfac.. haa to be

pretty high, i.e. the two componenta of the thermo electric

sy.tem are spring-loaded and t.. area of mechanical contact has

been min1malized as far as the construction of the calibratioa­unit allo ••• ·

Thi. is alao of importance fTom a thermal point of view.

2. the tempera,tuTe of the sy.tem is to be measured in the vflrt

spot ot .·c~::uita:ct between carbide and steel. As thu ie tpqeioal1y

impossible'the temperature ia measured in the centre of a air ...

oula1r area, the greater part of it being the contact surface.

'!'lie smaller this area is chosen, the greater the certa1.nQ' of

temperature equality throughout the contact surface.

,. temperature variations in the are. of contact shquld be .~D~"_

11zed by re.ducing the heat flo. originating from thia zone

eltlulr into' the workpiece material or into the aarbid. rod. fhi.B

caB be done by reducing the effectlve diameter of both th. rod

and the 'workpiece material to a very small ai •••

The calibration unit is _ho.n in fig. 1. As mentione\'! beforjt the carbide rod ia used on dual purpo ....

In the array according to fig. 7 it i_ used as a aalibratio.

rod. In the experimental cutting technique it is used aa a tool

to provlde points of reference with respect to carbide bit.

.hich are .elected at random from a lot of equal gr.4. aad

quality.

~--------------------------------------------------------------------------~

werkplaotstechn'.k tec:bnische hogeschool eindhoven

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rapport nr. 0012

TIG-·1

C.ALI SRATION UNIT werkplootstechnlek

bIz. 11 van 14 btz.

:SYNOANIO

DR. P.C. VEENSTRA

technische hog.school eindhoven

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0-

to i-

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rapport nr. 0072 biz. 12 VBft 1"- btz.

In t~e construction of the calibratioa uait it baa .een care full,

attended not to intrOduce actiye thermocovples in parallel or 1a , .

seri .. with the oae being the aim of iaye.tigatioa. To this purpose

both the workpiece material aad the carbide rod extend up to .•

considerable distance from the heating furnace while all joiats

to 'differ,en1;' aaterials are kept at icetemperature. Recorded. are

s1multaaeou~11 the temperature of the cold joint, the temperature

of the hot joint b1 means of a Cr-Al thermocouple and tJ:a.e eleotro--" mot,i ... e force of the 87stell a8 is clear froll the figure .. MereavO'

provisions are taken that at will a measurement caB be perfol'lle4

in a coapeneation circuit.

A special, and in our opinion a .er1 important feature of tile ~11 ...

bration is tile dynam.1cal w., of lIeu.ring. So the oalibratlo11 18

performe~ either at incr".in& or decreaaiDg temperature &ad .. atopa are, inserted to allow the ."st .. eoulat1q of theJ'liOco'lllpl.

and furnaee reaching temperature-equilibrium.

Synchronous intersection of the three recordin.. renders reliable

calibration pOints, on the condition that the heat tlow throUCh .

the thermocouple is of a negligible 8Ilall amount.

This method of .easuring allows to account for the influeitee of

the phase-transitions (allotropic transitions) of the workpiece

material on the electromotive force of the thermocouple.t which

it is a partner.

The ettect is shown ."er1 clear17 in a t7Pical calibrat1.oa cur ....

according to fig. 8.

During the he~ting cycle extra heat is absorbed bt ~ •• ~st,. ...

to the phase transition Ac 1 at 723°0, the magnetiC transition

at the Curie point Ac 2 at·7?OoC and the Ac 3 transition at about

800°C.

The .. reactions result in a.relative l.ncre .. e of eleoveaoI1 ••

torce with respect to the "nol'mal" trend.

. / ,

During the cooling down of the system a decrease 1s 00.erve4."e to

the fact that in comparison with the grain size of the material a

considerable amount of material is participating in the proo ... "

the resolving power of this particular measurement is very poor.

werlcplaatltechnhtk technlsche "ogeschool eindhoven

.. ~

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t

'1 III on 'P 0 '1 c+

tl 0

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.i I\)

!Q .. ' V , :

v .... lfil f'" i ,1'

I ifOj

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1$'

'k'

'.,. .. *' i9O,'

"'" "0 ... a ..

a' , ""n I-' !'I • ..:.

\.N

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1t ,.-

15 -

20-

25-

30-

35-

.to-

SOl-

, \

rapport nr. 0012 biz. 14 van 14 biz.

The effect of phase transitions is observed oyer a broad temperatur.

region and not of course at one de·finite point of temperature.

Anyhow and apart from the problem whether these phase transitions

really occur in the zone of contact between tool-and chip the

measurement giye. an ord.r of magnitude of a "natural .. uncertainty"

. of the temperature m .... urement when cutting two phase materials

like steel.

A .econd important point is that microphotograph. of the contact

area haYe been taken after a number of calibrations.

The general trend is that the electromotive force of the system

increas •• as a function of the number of he .. ting and cooling cycles

of the system. By means of micro photographY' it can easily be shown

that a .erious deoarbonizing of the steel in the contact area

occurs as .. function of the number of cycles.

As a matter of fact the .Y'.tem Carbide - steel C45 deYelop_ pro-/

bab17 by diffusion into the 8ystem:Carbide/Carbon - pure iron -

eteel.

It is clear that the.e graduate changes of the compo.ition of the

partners of the thermo-electric system have a yery significant

influence to the thermo.electric properties.

In general the •• changes result in a calibration which lags with

real temperature.

In our opinion once this kind of calibration techniQue. being a

routine job they have. to be performed with fresh and carefuly

prepared components.

We do realise that probably the beatingtime during the calibration

up t~ the region of cutting temperatures takes too long.

I_t might be useful to flash temperature up by means of high power­

high frequency heating in order to obtain a calibration which with

re8pect to time gets into an order of magnitude comparable with

the cutting proce8s.

By now develop.ent and experiments are directed this way_ At the

mean time atte.psare made to increase the thermal resolving power

of the system in order to get more detailed intormat1qn on the

effects of phase transitions.

werkplaatstechn 1.1e technlsche hogeschool eindhoven