__________

TRI D~~r az~cL

B ~n~~~~~~~ Q!O3S ?57~~~~~~~~~~~ O W!E5tER MA5S

AISC—c YR—Tb—LAUZF I ED

_________ IEND

DATE I_Eu FILMED

_____ 2—77

II

Al

1.0 L~~~ 2 5

_ _ _ ~2 2

1 . 1 ~ ~r 2 O

• _ _

.25 Bh11~ urn

Y I I~ j S(I1 U ~. 1

-~

[AD

ANMRC CTR 76-16

GRINDING, OF SILI CON NITRIDE TURBINE BLADE SHAPES

JUNE 1976I.

SPENCER LI. BAKERNORTON COMPANYWORCESTER , MASSACH USETTS 01606

FINAL REPORT - CONTRACT NUMBER DAAGLI6_76 _C_0024

Approved for public r&esis; dIstribution unllmited.

Prepared for

ARMY MATERIALS AND MECHANICS RESEARCH CENTERWatert~~n, Massachuset ts (p112 D D C

~~jpr~ rpm nr~~ j~U’ JAN 25 ~TT 1111

a— —I- -

~~~~~~~~~~~~~~~~~ ~~~‘

~~“ j

-~~~ ~- --- - -—— —

1-. ’

Ilk j

Ths flndln, In th pon m t,u,d..noffIcl.lDsp.r~nsnt of th. Army posétlon, unisis so ~ s~piswd by othsraithorlud documsn~.

Msn~on of soy tr ds nsmss or ~~~~~~~~~ In this mponthsél not bs conslru.d M~snhln nor a so officlil

-

-

lndwmons4lt or ~ipror& of suséi pro~acts or compinis, bydi. Unft.d Status Giw.nim.nt.

DIUPOSIf ION INSTaUCT1ONSDsuWo~ ~ Is ‘soso ~~~ ~t Is us ~~~~_ noa~OS ø~~ fl~wu Ii us d~ Ii ~~na.

•~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

— -

— -~~~~~

UNCLASSIFIEDSICUR SYY CJ .A~ $IFICATION O~ THIS PAGE (Rb., Sal. Søii ,•d~

BEFORE CONPLET1NG P00WEPORT DOCUMENTAT ION PAGE REA D DS$TRUCTIONS

~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~

ACCESSION NO S. RECIPIENT S CATALOG NUMSIR

~~~~~~~~~~ L IT,tr?L11~IPlUIr.1 Y~~. —~~ ——~~~~

—rtu ~~ o cov E ~~

GRINDING OF SILICON NITRIDE ~~JRB Fina l )(ep~~t.~~BLADE SHAPES,

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _~~,,

~~~~~~

-_

~~~~~~~~~~~~S ff l r —-“ i—i ~~~~~~~~ ..ü~ u

~~~~~~NTRAc T OR ~~~~~~ ~~~ R(a)

Spencer H. /Bake~l ~~~~~ _ _ _ _ _ _ _ _ _ _ _ _ _ _~~~~~~~~~~

1sar

~

,

_ _ _ _

iwrton company 4Worcester~ Massachusetts 01606 _______________________

10. PROGRAM £LEMINT. PROJ ECT TASKA R I A S ‘0

S. PERFOIINING ORGANIZATION NAME AND ADDRESS

(2~~~________________________________________ OE 4741qencv AccII - CONTROLLING OFYICC NAME AND ADDRESS ~~~~~~~ ‘2. REPoR T DATL_.~~

Army Material s and Mechanics Research Cente June ~~76—Watertown, Massachusetts 02172 17

___________ ME S A OORESS(II diU.m.e i from Coni,oUin4 Offic.) IS. SECURITY CLASS. (of ihi. raped )IA NONIT IN GENC

line lass i fied111 OECLAS SIFICATION ’OOWNGR AO ING

SCM £ DU LE

I$. DS$TRISUtION STAT EMENT (of ihi. Raporf)

Approved for public release; distribution unlimited .

Il DISTRIUUTION STATEMENT (.1 A. .b.1,.el .øt.,.d In 91.ck 20. II dlll.,. -nS from R.p.M)

IS, SUPPLEMENTARY NOTES

IS KEY WORDS (C IMuS all mv.r.. aid. if ..c...al ’y a,d S*nilfy by block n~~.b.r)

Silicon nitrideMachiningAirfoils

20. A~~~ CT (C.~EMu. mv~~a. aid. If n.caa.~~~ ~~d I*nII ~~ by bleck nomb. ,)

~~ The objectives of this research program were to developmachining techniques which could be used to grind a small, onepiece gas turbine rotor out of a fully densified silicon nitridblank. Metal bonded diamond cup wheels and mounted points wereused to drive abrasive slurries in accomplishing the machining.A few sample blades of fair quality were machined using themounted point system, but the stock removal rate was found tobe too low to he co~~.reiAl1v fa&eib1~

DO ~~~~~~~~

1473 EOI~~ION OP NOVAS IS OSSOL(TE ‘V UNCLASSIFIEDSECURITY CLA$SIfl CA?I ON o~ TsstS PAGE fUV~m1 Sd.. t.wm.d )

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

--

- ~~~~~~~~

- _ _ _ _

UNCLASSIFIEDISCUSItY C~ A$SIPICAtIOM øP TNt , PAOS(~~ 005

UNCLASSIFIEDSECURITY CLAUIPICATION OP twul PAOE(~~ mI 5.1. Fnr.. 4)

CONTENT S

Page

• FORWARD

ABSTRACT

Aims and Objectives 1

.- Results 1

- Problems and Solutions 1

A. Mounted Point Grinding 1

B. Cup Wheel Grinding 3

Conclusions 4

I[

-

,

.

_

I tTAB LES

Tab le I Machining Data and Calculations 5

Tab le II Cos t Calculations - Di amond CoatedMounted Points with Diamond Slurry 6

Table I I I Cos t Calculations - Diamond CoatedMounted Points with B 4C Slurry 7

EXH I BITS

Exhibit A Ceramic Blanks Used in MachiningTest 8

Exhibit B Ceramic Blade Contour 9

Exhibit C Sample Shapes of Ground SiliconNitride 10

Exhibit D Di amon d Coated Mounted Points forContour Grinding 11

Exhibit E Sample of Di amond Coated Tooling 12

Exhibit F Diamon d Coated Cup Wheels forPlunge Grinding 13

- ... ~~~~~~~~~~~~ ~~~~~~~~~~ PLW~ ~7J~~’.r -

FORWARD

This report was prepared by the Industrial Cer amicsDivision of Norton Company under Army Mátérials and MechanicsResearch Center contract DAAG46-76—C—0024 and covers work per-formed during the period November , 1975 to May 1976. Thisreport is the final report and summarizes all activities underthe contract. The AMMRC Technical Monitor for this projectwas Mr. George E. Gazza.

~~~~UIM tu

SIHs —

NC ~~~~~ o

0

I,

~I_ _ _ _ _ _ _ _ _•Ii

- ________ _ _ _ _ _ _ _ _ _

IABSTRACT

The objectives of this research program were to developmachining techniques which could be used to grind a small, onepiece gas turbine rotor out of a fully densified silicon nitrideblank. Metal bonded diamond cup wheels and mounted points wereused to drive abrasive slurries in accomplishing the machining.A few sample blades of fair quality were machined using themounted point system, but the stock removal rate was found tobe too low to be commercially feasible.

-~~~~ -. - -— - -~~~~~— - —--- _ _ _--

~~~~~

----

~~

- - - - - - --

AIMS AND OBJECTIVES

The object of this investigation is to determinethe machining parameters and feasibility of machining simpleairfoil shapes from fully dense silicon nitride by smalldiameter mounted point tracer machining and by multiplecup wheel machining. The mounted points and most of thecup wheels are metal bonded diamond tools of varying gritsizes. The material ground is Norton s NC-132, high densityhigh strength silicon nitride. Because it is difficult tomold this material into complex shapes, this work is aimedat developing methods of machining a high speed ceramicrotor out of a single monolithic ceramic blank . This reportcovers wheel grit sizes, clown feeds, surface feeds, surfacefinish, thickness of cup wheels, and amounts of chipping orfracture. The report specifies grinding conditions, cuttingrates , wheel wear , finishes, accuracy, and estimated costdata for each method .

RESULTS

Hot pressed silicon nitride is difficult to machineby any method. This is because of its 2200 Knoop hardness,and its density which is close to theoretical. It is possible,however, to machine airfoil shapes by both mounted point grind-ing and by cup wheel grinding , but these grinding operationsare slow. In the case of mounted point grinding, it tookabout four hours to machine a blade from a blank. Thus, for a30 bladed rotor, about 150 hours would be required. The cupwheel grinding turned out to be unsuccessful in the case ofdiamond coated tooling wherein a good deal of chipping waswitnessed due to the high pressure caused by a high wheelcontact area . Resin bonded diamond cup wheels caused almostno chipping, but the operation was even slower than the dia-mond coated cup wheel due again to the high contact area .

PROBLEMS AND SOLUTIONS

A. MOUNTED POINT GRINDING

A small Gorton Tracer grinder was used to end grind asmall blade shape out of an NC—l32 billet . The NC-132 billetwas 0.71 x 0.71 x 1-3/4 inch long. A 0.050 inch slice was madedown the center of the billet to a depth of 3/4 inch. SeeExhibit A. This billet was then used for machining two turbineblade shapes shown in Exhibit B. The billet was cemented in

a1

steel cup shown in Exhibit C. The grinding was done with3/16 inch diameter diamond coated mounted point s of variousgrit sizes. The steel profile of this point is shown inExhibit D . The coated po int is shown in Exhibit E. Themounted point was guided manually by a blade shaped cam madeto 10 to 1 for accuracy . The Gorton Grinder was equipped tovary the grinding RPM from about 1700 to 12 , 000 , but we chosefrom past experience to test the speed range from 2700 to5000.

The first test performed was at 2700 RPM with a 60 gritdiamond point. A cut was made to 0.70 inch depth in a singlepass with water coolant in the surrounding cup. See Table Ifor machining data. We were not able to apply enough pressureto maintain the grinding action and found that one point wouldonly grind a length of cut of 0.010 inch before the sharpnessof the diamond was lost. In this report we consider the mea-sure of wheel wear to be equivalent to the length of cut aspindle can make before losing the cutting action of thesingle laye~ diamond coating. We found a stock removal rateof 0.006 in’/hr. Excessive pressure only served to break thepoints, and would have broken a thin blade shape had we beenable to progress that far. Because of the poor cutting actionand heavy chipping with this system, the test was cancelled .Finer diamond sizes would have shown even poorer performance.Better surface finish and accuracy than demonstrated in thisbrief test can be reasonably easily reached with finer abra-sives and more accurate tooling.

We then tried a system of introducing a loose diamondslurry in the cup and found that the cutting action could bemaintained to give a greater length of cut with far lesspressure. To suspend th~ loose diamond we used methaleneiodide, quite toxic. The first test was with a 105 gritdiamond point and 240 grit loose diamond. With a mountedpoint speed of 2700 RPM we were able to cut to a 0.15 inchlength before loosing most of the cutting action. There wasmoderate chipping with a rate of cut of 0.05 in3/hr. The same0.70 inch depth of cut was maintaine~i throughout all contour-ing tests except one as noted later. The blade finishing opera-tion for the last 0.030 inch of stock removal was the same asthe above roughing operation except that we used a 240 gritdiamond point coupled with a 400 grit loose diamond slurry.We made a 0.15 inch length of cut at 2700 RPM before loosingthe cutting action. This system gave 0.06 iri3/hr with onlyminor chipping at the top of the blade. A sample of two bladesmachined with the above roughing and finishing operations wastransmitted to AMMRC, as were all the samples shown in thephotograph in Exhibit C. The factory cost/blade was $319 or$12,500/30 blade wheel, as shown in Table II.

2

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

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~ .-

~ -

~~--—-.

~~~~~~~ ——

~~~~ ~~~— --

We then decreased the depth of cut from 0.70 inch to0 0.10 inch in hopes of achieving a higher stock removal rate.

tn the test we found that we could continue the cutting actionover a 0.22 inch length of cut but only with high pressurewhich finally broke the 3/16 inch 60 grit mounted point. The0.10 inch end of the point was worn smooth by the abradingaction of the 120 grit loose diamond . The stock removal ratedecreased to 0.02 in3/min. The previous roughing cut at the0.70 inch depth with the 105 grit point coupled with 240 gritloose diamond had given us 0.05 in3/min. We therefore aban-doned the shallow cuts because of this low stock removal rate.

In a search for higher stock removal rates and lessmounted point wear , we increased the RPM to 3300 and again to5000. tn both cases poorer performance was found. Both testswith the 240 diamond p~ints and 400 grit loose diamond slurryyielded only 0.0025 in’/hr stock removal, and in both teststhe cutting action stopped after a 0.04 inch length of cut.

It became apparent that the loose diamond slurry wasabrading the diamonds on the coated diamond points. In orderto reduce this wear we turned to a softer abrasive slurry ,boron carbide. Here we found the cutting rates about the sameas those with a loose diamond slurry , but our wear was reducedto about one-third giving three times the length of cut foreach spindle. On the second set of blades we used a roughingoperation consisting of 120 grit boron carbide slurry . Thesuspension agent was cloroethoxyethane and tetrabromoethane.roughly 50/50. This roughing method gave a stock removal rateof 0.06 in3/hr and a total length of cut of 0.36 inch beforethe pr int had to be changed . Chipping was moderate. Thefinishing cut was made with a 240 diamond coated point coupledwith 400 grit boron carbide. Here the stock removal rate was0.03 in3/hr. This point cut 0.20 inch of material before need-ing replacement. The finishing operation was performed on thelast 0.030 inch of stock around the blade contour. A sample oftwo blades machined with the above techniques is pictured inExhibit C. The factory cost/blade was $169, or $6,400/30 bladewheel. See Table ‘(II. The RMS was the same as with the dia-mond slurry, about 100 RMS. Better surface finish is availableby finer diamond grits on the points.

B. CUP WHEEL GRINDING

We attempted to contour blades out of Norton ’s NC-l32material by the use of cup wheels. For this test we triedboth the diamond coated metal cup wheels and a resin bondedcup wheel. The diamond coated cup wheels were about 1 inchin diameter with wall thicknesses of 0.020 inch and 0.040

inch3

as shown in Exhibit F. One set of cups of the two wallthicknesses was coated with 105 grit diamond , the other with120 grit. Based on the best abrasive system developed duringthe mounted point contouring test we chose to try the 1 inchcup x 0.040 inch wall coated with the 105 grit diamond opera-ting in a slurry of 240 grit boron carbide. The 500 RPM gave130 SFPM about the same as the best point grind ing test. Weplunge cut the cup into the top of the 0.71 inc’h x 0.71 inchbillet and cut to a 0.70 inch depth as shown in E*.hibit C.The first cut was made in 15 minutes, the second in 30 minutes.The third cut could only be made to 0.150 inch depth in 30minutes. Microscopic examination showed that the diamonds onthe end of the cup were worn flat. Because of the cost of thecup wheels, $142 each , the high level of fracturing of thepiece, and the slow cutting action, we discontinued furthertests with this type of diamond coated tooling.

We then tried a 3 inch resin b~~’ded cup wheel made speci-fically for this test at a cost of $lsO. The wall thicknesswas 1/8 inch with a 1/8 inch diamond depth in 3Dl20-R100B69.The 1/8 inch x 1/8 inch diamond section had a slight reversewedge to avoid jammi~:g in the cut. We used a normal grindingspeed of 5300 RPM to give 4200 SFPM. Water was used as thecoolant. We were only able to cut to a 1/2 inch depth in 4hours even when we applied constant dressing to t’z~e wheel face.During this test we lost 0.020 inch of the usable diamonddepth. As with the diamond coated cut wheels, the surface areawe were trying to cut was found to be too great. However, theresin bonded core drill cut cleanly with minor chipping as canbe seen in the sample shown in Exhibit C.

CONCLUS IONS

Neither of the mounted point grinding techniquesappear to be economically feasible for production. Thediamond coated points coupled with a loose diamond slurryshowed an out-of-pocket cost of $319/blade while the diamondcoated points coupled with a loose boron carbide slurry at$169/blade. It is difficult to envision improvements ineither technique sufficient to make grinding of blade ringsfrom a solid billet feasible.

Stock removal by cup wheel grinding appears to bealtogether inadequate. Diamond coated cup wheels coupledwith an abrasive slurry chip the workpiece badly, an effectundoubtedly due to the dulling of the diamonds on the thinbase of the cup. Resinoid cup wheels grind far too slowlybecause of the high contact area of the workpiece.

4

___________ .‘.-~~.--— ,-.- .-——-, -.~~~‘— ,

C)4) N

.1-4 0 0 t’)Ct) ~~ — 0

~~ U, ~~ 0I—— ’ ~O ~~ (—‘414 0 U, (4 0 0 •0 t’ 4) X 0 C) ~~.~~~ 0 0 0 0 0 0 0 0 0

4) . 4 ~~~ . . . • . 0 1-j 4.4 m 0 0 0 0 0 0 0 0 U

—c~ ~~~~ ~~~ L) ” —’ .-4C) p.

p..~-f 4J ~~~~)F—’ ~~~~ ~~ O~ C)

U -4 1~~ U, C) C) U, U, C) C) 4-~ I14 -~-4 ‘-4 t~~ ‘ 4 ‘l ‘-4 ‘-4 ‘-0 ‘0 04 >- 14

“ ~0.. ’—’ 14 CC ~~U 4) 0 •-4

~ = ~C)Cl) C) ~~ C) 0 0 0 0 0

C) U, C) C) C) C) U, C)~~ U, ‘4 I—4 U, — — (~1 —

0 4 )

o , 4 4 -—‘ 1 ~~ • 4-’ 4-~ 4-’ 4-’—4 ~~~0. 04 ~~ .~~

• ~~~~ .~~~

•

4-’ 01 CC 0 ~O ~~ bO -~~ bO

CC O~ 4-4 .,-4 C~ E •,-4 0 .p-4 - i-I 0 ~—4 L ) O ,~~~ ‘ 4 E ‘-4 ‘-4 E r-4

UU-4

CC 1-4U

— 4-’ — U, ~~4 (‘4 ~~ ‘0 0 4) 4-40 ‘-4 —4 r~i 0 0 t’~ (‘4 0

• . . . • . CC-~ CC C) C) C) C) ~~ C) 0 0 0 .~~

-~ 4-~ U4) 4) 4’)

4.) -~~ 0 4.J :

cC CC (‘4 (4 00 € 4 E C) ~-i.’ t i €4 ti ~ 4 €4 ri ri ri 0 -4 ~~~ 0-~~

. . • . . . . . 14 00 .~~4-i ..-4 C) C) C) C) C) C) C) C) •0 p.

cCU 1-’ ‘0

4.).~~‘ .~ I C)

4-~ I 0 0 C) 0 C) 0 0 0 4-’ EU ~~ ~

.. N. ~~ ~ 4 N. (-. N. ~~ 4’) ~~CC 4)] . . . . .

I C) 0 0 0 0 o o o 0CC U 4-4 -1

-~~ 4) O C ~ -.

~.1-f C) ~~~

-~~ ~~ ~~ U U ~~ cC~~~~ U 4 ~4 4.i

I-i ~~4 •.-4 ~~ ~~14 ‘~~~ 4-’ 0 ~0 4) 5 U cfl 4) C).1-4 ~~

{~C)) 4.4 4) ~~~~•.-4 4-4 0

-4 N C) C) 0 C) C) 0 0 4) 0 ‘~~ 0 1-’ ~4) 1-. ..-4 I ~~ C) (‘i 0 0 ~~ C) .~~ 0 7~~ C)) (.1 ~~ ,-4 ~~ (‘4 ~~ 4) 4.4 4) ~~ CC S

.1-f 1-4 4) p. 4.4 .,-4 4.41-. CC 0 >. ~~~~~~~~~~CC 4) 4) 4)~~~~ 1 4 4 . 4 ~~~ 4 ) (~~.,-4

14 0 U ‘~~~ ~~~ 4 . 4 0.0 C) C) C) C) C) ~~ ~ 0 C C 4)~~~- 4 C ) e- 4 ~~~~~

f , U ~ 5 u ~~ 5 CC 01-’ I I I I

X C) 0 0 0 0 0 0 0 5 5p. 0 0 0 0 0 0 0 0 4-è ~~ CO U C) • ‘-4 4) p.

-~~ ~~ r- r— r— r-~ ~~ ~~ r-.

~-. 4.4 )4 ç~ S

~ r’i ti ri -i t’t U, (.4 4)0 4 ) : 4-’ .-~E 4-”O~~ 4-) Q)

,-4 .~ 4 •.4 N 0 U, C) 0 0 0 0 0 I I

- I-f 0 •— 0 14 • -.0 0 ~~ ‘0 ~~ NiC) U u’i 0. ~~ (I) ,—4 Ni r i Ni ‘-4 ri — Ni

S

- ,- ‘

- . ~~~~~~~~~~~~~~~~~~~~~~~~~~ - ~

-, ‘-‘-- .

~~~~~~ ~ ~~~~~ ~ ~- “. - ~~~~~~~~~~~

11.

TABLE II

COST CALCULATIONS

Diamond Coated Mounted Points with Diamond Slurry

The only methods of grinding small blade configuration whichseem at all reasonable are those which involved point grindingwith an abrasive slurry . The time to do the mach ining seems slow ,but the quality at least seems reasonable. Below is shown thecalculation of the out-of-pocket , or factory cost for the diamondcoated mounted points with diamond slurry .

DiamondSpindle Diamond Hours Number ofGri t Slurry 2 Blades Sp indles

Roughin g Cut 105 240 5 12

Finishing Cut 240 400 2 5

Miscellaneous 1

8 17

Assume d cos t per hour $18

Cost per spindle $29

Factory cost/2 blades $144 $493

Factory cost/blade $ 72 $247

Total Factory Cost/blade $319

Estimated Factory Cost per 30 bladed wheel $12 ,500(including a better blade and root finish

at double finishing cost)

NOTE: The factory cost is an out-of-pocket cost and doesnot contain the normal overhead cost, rejection rates ,setup costs , j i g ging, e tc ., and should not be construedas selling price .

6

—..~ .- ‘—~- - ~- r— ””p - - -~ --~~——~ - — - - - ~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~ . -.— — .. ~

. - -

.-------- --- _

TABLE III

COST CALCULATIONS

Diamond Coated Mounted Points with BpC Slurry ~

DiamondSpindle B4C Hours Number ofGrit Slurry 2 Blades Sp indles

Roughin g Cut 120 240 5 4

Fin ishing Cut 240 400 2 2

Miscellaneous 1

8 6

Assumed cost per hour $ 18Cost per spindle $ 29

Factory cos t/2 blades $144 $174

Factory cost/blade $ 72 $ 97

Total factory cost/blade $169

Estimated Factory Cost per 30 bladedwheel $6,400

It should be noted that a 0.050 inch slot 3/4 inch deepwas made in the center of the billet at a cost of around $8for each cut. Had this cut not been made , the spindle grindingcosts would have been about 10 percent higher. The abrasiveslurries are reusable and considered a neglible cost.

7

-

-

~~~~~~~~~~~~~~~~

‘

~~~~-

‘-~~~~~• -

9~I3~--~-: •

~-~~~ J~ ’

) ,~~~~~~~- -~~~~ ~~~~~~~~

SLOTTE D SOLID

for Blade Contour Grinding for Cup Wheel Grinding

ff / / ’f —

I I i If ii lil a Il II ii IIu ,

~ &—II \‘ \ \ ‘~‘L _ _ _ _ _ _ _

~~~~~~ — —— Th 1 i I , I I ~~I I I I ~I:

______ _____________

i i t i t

I : : 11 ’ :;~ : :~‘ i i ’ I I I .7o’I i : 1 1 ’ ii I i

I i II ‘ )

_ _ :~.: J~~~ h_ 1JJ_ e~~~~. Li Li L4 —

i~A

1 1 1

5ca/e: 2X

EXHIBIT A Ceramic Blanks Used in Machining Test

8

‘I ____________________________- . - ‘ I’ - ‘ ‘~ r ’— ’ • ‘ I ~~~~~~~~~~~~~~~~~~

-7--—-— __,_i.- ~~

‘- ~ ~ ~~~~~ ‘~~~~~~

-

~~~~ ~~4 - ~~~ .,,~ ~~- • - — ___ _ __ _

- --

.4

~~ 9,O?~~s~~~

____________ • e%O _________ _____________________________________

_ _

~!j~

EXHIBIT B Ceramic Blade Contour

t

9

________ ~~1*J1 PPT’ :. ~~~~~~~~~ ~~~~~~~~~~~~~~~~~~~~~~~~ S . ‘T

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~‘~~~~~~~~~~~ ‘

-

.

.~~~ ‘ ‘ -

14

A - Grinding setup for loose abrasive slurriesB - Diamond spindle with waterC - Diamond spind le with loose d iamondD - Diamond spindle with loose boron carbide£ - Diamond cup whee l with loose boron carbideF - Resin bonded cup wheel

EXHIBIT C Sample Shapes of Ground Silicon Nitride

10

— - - - -— ----- --.—-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~

- - .. ‘ . -..~~~

-— t. . .—. -. - ,--. ~‘.~~~

- ;‘___.-‘~

---___ - ‘- -‘-—.,—---—-- —

H P

_ _ _ L

.11

— ~4 _ — — .~___ I

/ c0 1177I ~~

‘— • 010I - eaoR

—-j---~~~~

EXHIBIT D Diamond Coated Mounted Points forContour Grinding

11

_ _ _ _- ~~‘:, _ _

C D

A — One inch core drill - 105 grit diamond coatedB - One inch core drill - 120 grit diamond coatedC - 3/16” mounted point - 120 grit diamond coatedD - 3/16” mount ed point - 240 grit diamond coated

EXHIBIT E Samples of Diamond Coated Tooling

12

_____ —__

Th4#i~~I~~~~~~~_ - — — ~~~~~~~~~~~~ —

_ _ _ _ _ _

~~~Ø oir~~~7_ -

I’!I

-.

,

0

- - — — — — - .

‘7f’ 1cooYec/ c/~o%~I ii

wa/I _JL i i

0.201 . 040

EXHIBIT F Diamon d Coated Cup Wheels forPlunge Grinding13

—- . -— -

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~

F— — — — — — — — —

II- -~ a O . . I- . ~~ ... , .c 0— — U.S~ C •I ~ ~~~

... i ~• ~~~~I ~~~~~~ I -:0_ c 0 ~~~~~— _ . I . s _ — c• $ 0 Q ~~~~~ — — I -

— A c — ’I ~-~.0 t_ Ia ,

I I0 ~• — — . Ii ~

. ‘ —

0 0 0 — ~~‘0 1 •I — —~~ ~~S = £ 0* ~ .c 4 • A .~ t~ -i

-

• ~~~~~‘ ::~ ..

~~-

I c . . ! . - ~• _ • - FI £ ~I ~~~~— 0 — S ..’ •I~ Z I. •‘—~~ ‘- — O ~~)~ -

~ ~~~~~~ ~~u— —~~ I

~~ ~: !-

~~~~~°

i ~:°‘~~ a ~~~~~~ o .~ ~~~ ~~

~~~~~~~~~~ I

~~~~~~~~~~~~~~

~~1.I111 1111110 .1.1..... — — — “1

~r ~ ; ~~; - .

-F

I I ~~~~~tF I p

I

w: J a llh1IT~ ~ r

~• a:; : ~~~~ ~ •

~ . 0 0 ~~. F l

• p ~I ~~~~~ ~=.: ~~~~~~~~~~~ —b~:~ 1~ I _

_-~~~~.‘.

‘ ~~ ~~~~~ : ~i~-~li-F S

L _ — — — _.~_. —— —

~-F0• ~~,~~~-V0—.—• ~ ~~~~~~~~~~~ ‘_ . - -.. - , ç.

~ •- -