Note: Descriptions are shown in the official language in which they were submitted.
21 ~,3~/~t9
Borosili~ Glass
The invention concerns a 6Gro~ te glass having a linear U,erl.,al ex,ua"sion
be~:een 20~C and 300~C of 3.9 to 4.5 x 10 6K '.
It is used for manufacturing laboratory glass, housecl~I glass, ~,har",~ce~ ~tic~l
recept~cle glass, lamp glass, flat glass, as well as other industrial and optical
high-quality glass produc'ts.
In accordance with the invention the new glass is used when a borosilicate
glass with the ",e, ItiGI ,ed pro,uel ~ is to be man~ ~f~ red in known fully
electrically heated melting plants according to the cold-top principle.
Many types of bor~silic~te glass are known in the state of the art. Theproperties that det~r",ine their use-value are high chel"ical lesiak~l ,ce, low
thermal expansion, high U,er"~al fatigue r~sistance, and high mechanical
stability.
Thus, borosilicate glass 3.3 is usually used for laboratory, housecraft and
instrument glass in accordance with DIN ISO 3585 . This type of glass
cGntc.;.,s only a little alkali (less than 5%), SiO2 more than 79% and B203 to
approx. 13%. It has a thermal e~ansion of approx. 3.3x10 ~K
Fu, lhell"ore, sealing glass that contains boron is known. It has a high alkali
and/or all~line earth CGI~IIt, as well as sor,-~tir"es ad.lit;G.,al further oxides.
The U,err"al e,.~l,sion of these types of glass is 3.6 to 5.2x10 ~'. A further
21 93~99
known group is that of so-called neutral ~vhar-"aceutical borosilicate glass. IncGnbd~l to the sealing glass it achieves the l,ighest chemical resis~nce
values. Its alkali colltent is approx. 6.5 to 8.5% and 3.2% to 5.0~h alkaline
earth, the thermal e~,uansiGl) is 4.8 to 5.1x10 ~K '.
It is known, as desc,il,ed in patent specificdtiGn DE 37 22 130, to replace the
large range of types of bor~s.'i~~te glass by a glass, which satisfies most
requirements, of thermal eA~ausion 4.0 to 5.0x10 ~< '. It is also known to
improve and speci~'.se ~e.r~r.nance-det~r-..inir,g properties of borosilic~te
glass by means of an o~tin,ised cGm~osition and partial use of additional
oxides such as ZnO, SrO, CsO, Li20, etc., as desclil ed in, e.g., the patent
specifications DE 42 30 607, DE 40 12 288 or DE 43 25 656.
In the case of industrial production of borosili~ ~ glass 3.3, bec~ ~se of
improved ei~ergetic e~iciency, qualitative as well as ecol~gic~l advan69es, fullelect~ ic ll.elting after the cold-top process has prevailed. In this ~r~cess, the
melting heat is gener~t~l in the interior of the melting bath by means of a flowof electlic current, whereby the surface of the n,elti"g bath is continuously
belayed with new batch. Normally a stable, ~lficiel tly insulating layer forms,
which also retains volatile s~ s~nces and re-s~ ~r~'ies them to the melter.
Owing to this su~.eriG. ity and its cost cuffing relevance, the known borosilicate
glass is invesli5~t~d for fabrication acco~di"g to this ~ thod and i1~; devices.
21 93999
Thus far it has not been possible to melt neutral ,.~har,n~ceutic~l borosilic~t~glass fully electrically, since the required refining agents As203 andJor Sb203
destroy the usual molybdenum rod hedtin~ electrodes. Initial a,~,uroacl.es
toward a ~,rocess engineering problem solution are specified in DE-PS 43 13
217.
Borosilicate glass having a linear thermal expansion from 3.6 to 4.8x10 ~K 1
can only be melted full electrically under severe qualitative lin~itdtiolls. It melts
significantly faster than borosilic~t~ glass with a thermal expansion of 3.3x10 6
K ' owing to higher flux cont~n~ ~alkali, alkaline earth and boron oxide).
However, bec~use for complete glass forllldtiGn, hGIllogenisdtion and refining,
approximately the same melting temperatures are required despit~ the flux
CG nlerlb, the efficiently insulating, cold batch layer required for the full electric
cold-top ",elling ,~.rocess cannot arise in a stable ~)lanner; the heat bc.lance is
disturbed. At the worst the process no longer al!Qws thç açhiçvçmçnt of thç
desir~d telnperat-lres, so that bubbly glass or u..i..ell_d particles leave the
furnace.
If alkali and alkaline earth are added as usual as the carLGnale, whichdepending on origin is co~ i.lindt~d with sulphate, the carbon dioxide and
sulphur dioxide arising during melting cannot be completely removed ~rom ~e
melter. On the one hand, the released gas q~a~ti~s are re!ative!y hjgh f,or
21 93999
the tough borosilic~te glass. On the other hand, the high s~l ~hility of C02 andS02 C~ uses excessively high gas resiciues in the glass. From other glass, it isknown that the sol! ~bility of C02 and S02 increases with the basicity module
(ratio of network transformers to network f~,r",er~). If one lralls,~)oses this
regularity to bolosilicate glass, the higher C02 or S02 solubility of the alkaliand alkaline earth rich borosilicate glass toi"pared with borosilic~t~ glass 3.3is then plausible. At the latest as reboil glass, C02 and S02 is again released
and appears as seeds or bubbles in the finished giass. Suitable refining
agents, such as As203 and/or Sb203, can remove these gases in
combination with further oxidants, they are, however, unus~'e in fully
electrically heated furnaces owing to their destructive effect upon molybdenum
electrodes. Owing to their high alkaline earth conte, It~, the gl~sses described,
e.g., in patent specil~c~tiG"s DE 42 30 607, DE 37 22 130 and DE 25 656,
have this decisive disadvank3ge.
In additioll, further, partially used oxides such as PbO, SnO, CuO, NiO, CdO,
FeO, Cr203 and ZnO act corrosively upon the Mo t~e~ lechodes.
Measures to protect the ele~t,o ies, such as the known r;,~tl,od for direct-
current passivation, are ruied out bec~ ~se of the required use of known noble
metal devices in the feeder.
Furthermore it is known that the full electric cold-top Illelti~ pr~ess, in which
the melting ten-perarture for every type of glass is deterr"ii ,ed and is especi~lly
21 9:39~9
-5 -
high in the case of borosilic~tç glass can only be used for a specific range of
glass viscosity and electric cond!~ctibili~r. A excess electric condu~tibility of the
glass at the usual ",elti"~ temperature owing to high alkali or alkaline earth
co, Itenb causes high current and energy densities overl,edli"y electrode
wear and blisters can occur. In the event of excessively low electric
conductibility an il ,creasi. ,9 part of the current flows through the stone
",at~rial. Fxcessive glass viscosity requires ul-~cce,c1-hly high temperatures
for refi"i"5~ or only enables this only incon":letely in a too thin-bodied glassunr"elted particles or unrehned melted l"dlerial are frequently mixed into the
finished glass. The full clectlic cold-top method proven for borosilicate glass
3.3 is consequently not transferable to other gl~sses which at comparable
,nelti"~ .".,~r~tures ha~e Ji~rent viscosities and condu~ ities without
significant cGnsequences. Many known types of L~r~,sili~c~ glass with a linear
thermal ex,uansion ~reater than 3.9x10 CK ' have e.g. a total alkali p~us
alkaline earth content of more than 7%1 also that from patent specifi~iion DE
37 22 130. They cannot be melted bubble-free at the required ",eltin~
te""xr~tlJres over 1550~ C with the proven full electric cold-top prvcess.
From the ~ ll ,o.ls known state of tne art references for fixing and controllingthe redox po~,ltial of ~Grosilic~te glass are not known.
~1 ~399~
It is the object of the invention to specif~r a soft borosilic~t.e glass of thermal
expansion 3.9 to 4.5x10 6K~' of high che~"ical resislal~ce, which can be
fabri~ated under the advan~eol~s eco logi~al and enerye~ic conditions of ~e
known full ele ~IIic cold-top process.
In aGcGr~l~a. ,ce with the invention this object is solved therein that it has aprocessing temperature at 10 4 dPa s of 1200 to 1 270~C, a \riscosity at 15~0
C of 1 O~'to 102 ~dPa s, a specific electric r~sisl~nce at 1 550~C of 20 to 33
....cm and an electric conductivity at 1 550~C of 3.0 to ~.0 ~/m, melts under
cold-top conditions at approx. 1 600~C with 0.3 to 0.5 mm/min, and has the
following basic col"position:
SiO2 + ZrO2 77.0 to 81.0 weight %
B203 + Na20 + K20 + CaO + MgO + BaO 16.0 to 18.5 weight %
of which Na20 + K20 + CaO + MgO + BaO 5.4 to 7.0 weight %
of which CaO + MgO + BaO to 0.9 weight %
Al203 3.7 to 4.9 weight %
Cl O.OS to 0.4 weight %
with the relations:
Ratio CaO + MgO + BaO 0.0 to 1.5
ZrO2
"- 21 q399~
-7 -
Ratio Na20 + K20 + CaO + MgO + BaO 0.060 to 0.075
B203 + SiO2 + A1203 + ZrO2
Adva,ltcgeous embodi,.,eilt~ are specified in s~ cl~NIs 2 to 5.
In the case of the borosilicate glass according to the invention specific
experiences wim the specified process and its devices are to be observed.
Although the principle relatio"ships l,etween glass properties and cGIl~posiliGnof borosilic~te glass are known, the ,vr~cess-linked limitdtiGIls lead to a new,per se cont,ddictoiy and U,erefore thus far unusual objective.
The new glass belongs to the group of chel"ically resistant bor~silicate glass,
ch-dr~cl6rised by the following properties: -
- linear lher",al ex~a"sion between 20~C and 300~C:
3.9 to 4.5x10 K~'
- l.al ~srorI"dtiGn teln,uerdtLIre: over 540~C
- hydrolytic resi~nce per DIN 121 1 1:
1 st ctass
- acid resist~nce per DIN 12116:
1 st class
- Iye resistance per DIN 52322:
2nd class
Owing to its use as ,~har-"~cellffc~l andJor housecraft glass, the glass is
credt~d without toxic heavy-metal oxides. It CG nt. i~s components to increase
'- 21 93~99
the brilliancy and can be ~ d. In order that it can be melted fully
ele~ bically in the known fu,l,aces it may contain no PbO, SnO, CuO, NiO
CdO FeO Cr203 ZnO As203 andtor Sb203.
For eco'ogi~l ~asons no fluorides are used as refining agents.
In order to maintain a low gas content in tne glass, during ~"elti.,~ e or no
carbon ~ cide and no sulphur dioxide is ~ le~;e~l.
In order to avoid the failure of noble metal built-in parts the glass does not
have a r ad~ l condition. The ability for influel~cin!a by means of the usual
oxidisil,g burner adjual",el-t is not available in the case of fully el~bically
heated " ,~lt;. ,9 plants. For ecological reasol~ the usual addition of nitrates (02
separdtiG" and oxi- l~t;Gn of polyvalent ions) is ruled out be~use of their
relea3e of NOx.
In ~ddition to the ,,I,~sical chemical glass prope,ties, the CGIl.pO~it;ol, of the
borosilicate meltable fully electrically under cold-top conditions also accountsfor ,l)r~ess-linked require",en~.
AccGruling to the inven~on the full electric cold-top pr~cess is usable for
borosilicate glass with a ll,er",al expansion to 4Sx10 ~' and enables a
good glass quality if high t~."p~r~hre physical cl.ara ~,ia~cS such as
viscosity and conductivity lie, for pr~ess r~asons in the proximity of those of a
borDsi~ ? glass 3.3. In order that stable cold-top conditions prevail, the batchis melted at more or less the same rate used for borosilicate glass 3.3.
2~ ~3qqq
In meltiny trials the fal'~ur;.,y of these values were proven:
- ~,rocessi"~ t ."perdture at 10~ dPa s:
1200 to 1270~C
- viscosity at 1550~C: 10Z ~to 10Z-YdPa s
- sp~cific elect~ic ~ t~nce at 1550~C:
20 to 33 Ohrn cm
- melting r~te of the batch without refuse glass:
0.35 to 0.45 mm/min.
By means of trial melts it was shown that the process linked high processi"
t~,l.per,Jt.lre speci~ed and the 1550~C vixosity could be achieved ~nth a
conbnt of SiO2 plus ZrO2 of more than 77% and a content of A1203 of 3.5 to
5.096. ~t above 81% SiO2 plus ZrO2 ~e processi".J t~r",~rature and the
VistG_ ~.y at 1 550~C incr~asa, but not to u..co, d.ollably high values and relicts
of these difficultto melt cG~IlpGllel~ts must be recl~n~ with. Under 77% SiO2
plus ZrO2, the linear thermal ~A~U&. ,sicn i- ,clec.ses over 4.5x10 ~' wffl the
Al203 cont~nt according to the inv~ . ~'bGI 1.
Furtl,e".,Gre it was ascell~;"6d that the process linked conductivity and the
s~c;fic ~le_b ic re~ 3nce specifiv~l fix the ratio of the sum of alkalis plus
alkaline earths to the sum from SiO2 ~ B203 + A1203 + ZrO2 at 0.060 to
0.075. Above that an ~ essive ele_t~ ic conductivity at 1 550~C over 5 S/m
leads to a high current density below that under 3 Slm too much current
2~ 939~9
-10-
flows through the stone material.
The sum of all oxides effective as fluxes ~alkali + alkaline earth + B203)
accelerates the melting behaviour. In order that the desired cold-top con.litiGns
prevail at melt;ng temperatures over 1 ~0~C required for ~ri"i.~g i.e. the batchsur~ace required for insulation does not melt this flux quantity may not exceed
18.5%. In orderto acl,ieve a batch surface cG,n,uarable to bor~silicate glass 3.3
up to this value at least 0.6~h of the required SiO2 is repl~ed by ZrO2 which
greater delays melting. Below 16~,6 flux the glass melts more slowly than
borosilic~te glass 3.3 this would require e~(cessively high temperatures and
the danger of the occurrence of residllal quarlz relicts. In dependei ,ce upon the
variable alkaline earth content ex~lained below the melting behaviour is
stabilised by a d~ined increase in ZrO2 in that the ratio of alkaline earth to
ZrO2 is maintained below 1.5.
As is known the B203 CG ntent influences the chemical resia~ance and is
limited downwardly by an ex&essive proceâsil Ig te~ uel~dt~lre over 1 300~C and
an ~xcessive 1 550~C viscosity. In cG""ection with the alkali and alkaline earthcontent explained below, a range of 10.5 to 12.5% B203 was det~r..,ined in
order to achieve the required cher ,ical resistance.
As ex~erience shows linear thermal ex,uansiG" is greatly influenced by the
alkali and alkaline earth cGntent. It was possible to det~r-"i"e that whilst
~ ~1 939~C~
accounting for the limits of alkaline earths for conductivity and ca, LGndte
addition, the arguments for which are below, at least ~.4%, but at most 7.0~h
alkali plus alkaline earth may be used to maintain linear II,er."al ek,uansion
between 20~C and 300~C in the range of 3.9 to 4.5x10 6K '.
Furlherr"ore, it was found that the desired chemical resi~la"ce can then be
achieved with utilisation of the mix alkali effect and additiGnally the mix alkaline
earth effect if, in addition to 5.0 to 5.8% Na20, also 0.3 to 1.5~,6 K20 or 0.6%to 0.9% alkaline earth, or a cGi"bindtion of K20 plus alkaline earth, is added.
Since among the all~l;"e earths, BaO demo"~l~ates here the desired effect, as
well as owing to the advantages explained below, it is preferred. Rec~use Li20
would increase the devitri~ication tendenc~, it is not used.
In addition to its effect of delaying melting, as is known, ZrO2 improves
chemical resi~l~nce, es,~eci~'ly agai"s~ Iyes, the ",ecl,a.,ical s~a"~th, and
especially the scratch hardness of the glass, which provably i"creases its
service value, as well as also the e~,~,ense in the case of mechanical working.
In order that the glass can also be worked ecGno"~ic~lly, the ZrO2 content is tobe below 2.4%. Surprisingly, in the event of mass prod~ ~ction of this glass, nothreat of devitlificdLiGn could be established up to this value when Al203 is 3.7
to 4.9%. To limit the proce-~sing temperature, the Al203 contei It iS preferably4.1 to 4.5% and the ZrO2 content preferably b~tw~en 0.8 and 1.09~.
21 93999
In industrial melting trials in fully electrically heated cold-top me:tirl~ fu..,aces
and subsequent determination of the gas content it was furthermore found that,
with a ratio of Na20 + K20 ~ CaO + MgO ~ BaO divided by SiO2 + Al203
ZrO2 + B203 of less than 0.075, the C02 and S02 contents in glass clearly
declease. In order to generally maintain low introd! ~ced carbon and sulphur
dioxides quar,lilies, in accordance with the invention, the use of alh~l;ne earths
is limited to 0.9% and the use of carLo"at~s only per."itt~d for these alkaline
earths. Other carbonates or suplhates or raw ",dt~rials contai~ ling ca~t Gna~s
or sulpl ,ates may not be used bec~use of their rel~a3e of carbon and sulphur
~ioxirle. MgO increases the devitl ific~lion tendel ,cy and is thus ruled out asraw material component. In cGm~arison to CaO, BaO increases the ref.d..ti~e
index and pro,l,otes the brilliance of the glass, as desired in use as housecr-dfl
glass. Owing to this property and its favourable influence upon the acid class,
exclusively BaO is used as the alkaline earth con,ponent. This is u"der~tood to
mean that only CaO and MgO impurities are permitted, which despite all
arrangements may enter the glass by up to 0.1%. To fully avoid reboil
susceptibility, the glass preferred accorJil~g to the invention is free of alkaline
earth, except for the tolerated impurities.
If the glass must be stablised, the introduction of a d~ned quantity of ceriu
IV oxide has proven advant~geous for lime-soda glass, as it oxidises polyvalent
impurity ions. It was found that the lelease of oxygen from the cerium IV oxide
~es not destroy the laterally or bottom installed molybdenum rod elec~odes,
~ ! 93q~9
-13-
since me r~le-~,ed oxygen no longer comes into CG~ Ct with these. Moreover,
it was established that the known cGr,osh,e influence ~F~ct~d by As203 or
Sb203 does not occur in the case of the quantity of cerium oxide used
acco, ~Jiny to the invention, des~ r~ the prevailing high ".elti"y te,~rdt~re for
sulphate-free bGro~ 'v glass. At the same time, tne desi,~d redox condition
is ~dj!,~s~le and co,lb~l'able U,er~ l,. 1 Io~/e~er, the CeO collh~.lt in tne glass
does not exceecl 196, as ~Jthe/ ~ise, in addition to an incr~ase in molybdenum
wear, negative ;"~ ent of the cl,en,ical resi~ance would occur.
A borosilicate glass accor~.ny to the invention with a linear thermal expansion
L_hr~en 20~C and 300~C of 3.9to 4.5x10 ~K ', a ll_.l;.f~rrlldtiGn te,n~ erdture
of 540 to 57~~C, a ~,rocessi. ~y t~ per~h~re at 10 4 dPa s of 1200 to 1 270~C,
and a 1 550~C viscosity of 1 02~5dPa s, which has a s~ecif~c ~31e t- iC resi~Lnce
at 1 550~C of 20 to 33 Ohm cm, and an elecl.ic conductivity at 1550~C of 3.0 to
5.0 S/m, and at the same time fulfils the first hydrolytic class as per DIN 12111,
tne first acid class as per DIN 121 16, and the second Iye class as per DIN
52322, has the f~llo~i.~y cGn.,ssition:
-
21 93~9c~
-14-
SiO2 76.6 to 78.0 weight %
B203 10.5 to 12.5 weight %
Al203 3.7 to 4.9 weight %
Na20 5.0 to 5.8 weight %
K20 0.3 to 1.5 weight %
CaO andJor MgO (impurity) less than 0.1 weight
BaO 0.0 to 0.9 weight %
ZrC)2 0.6 to 2.4 weight 9'o
Cl 0.0~ to 0.4 weight %
Only NaCI or KCI is used as a r~ning agent, As203 or Sb203 is ruled out.
The use of raw materials conatining CaO, MgO, sulphate, or fluoride, is
,~en..iU.ad only with the ~ ,Ai~l~ of the smallest impurities.
The bor ~ c-~ glass accor~ g to the invenffon requires no all~line earth
(apartfrom unavoidable impurities) and lllel~re fully P~lu~ies ff~e use of
c~. bGn~t~s. This lowers the reboil s~lsce~l,ility. The alkalis are introduc~
only as borates, aluminates, or silicat~s. This glass, which is pr~f~l,6d
according to the invenff~n, is cl,a.._ct~liaed by the following cG~ osit;on:
21 939q9
-15-
SiO2 76.6 to 77.7 weight %
B203 11.0 to 12.0 weight%
Al203 4.1 to 4.5 weight %
Na20 5.1 to ~.6 weight %
K20 0.8 to 1.2 weight %
CeO 0.0 to 0.5 weight %
ZrC)2 0.8 to 1.~ weight %
Cl 0.05 to 0.2 weight %
Es,uecially advantageous is that the borosili~te glass accordir,g to the
invention with its ch6"~ical colnpGsitiGn and its physical properties can be
manufactured using the full electric cold-top mellin!J process which is
ecclcgi~lly er,erg~ically, and operationally highly efficient. In such a glass
melting furnace the glass accordin.J to the invention with a linear thermal
expansion bet r/a0n 20~C and 300~C of 4.0 to 4.4x10 ~ a l,~nsfo",.aUGn
temperature of 550 to 575~C and a processi"y temperature at 104 dPa s of
1215 to 1 260~C tne first hydrolytic class according to DIN 121 1 1 tne first acid
class accorcling to DIN 12116 and the second Iye class accor.li.,y to DIN
52322 is melted and processed in good quality whereby telllpGr..rily and
reversibly re~,lacement by borosi' cate glass 3.3 is possible, rapidly and without
problem.
In the follo-:;.,g the invention is explained in greater detail by means of an
embodiment.
Glass nos. 5 to 19 shown in the table represent examples of continuou~ly
working, fully electrically heated cold-top melting f ",aces.
"- 21 93999
-16-
Glass nos. 9 to 11 were melted with 20 to 30% refuse glass.
Glass nos. 1 to 4 serve as a co,..parison and are m~ le fully electrically
according to the cold-top pr~cess.
Glass 1 concerns a t~orosilic~e glass 3.3 according to DIN ISO 3585.
~lass 20 serves as a comparison and cannot be man~ ~ured bubble-free
with the fully electric cold-top process (alkali plus alkaline earth too high
specific electric resistance too low, basicity module too high).
Remarks on the table:
Glass oxides in per( entages per weight.
Alpha: Linear mermal e~ . ,sion be~Nee" 20 and 300~C in 10 L'IK.
Tg: Tr~nsf~Jrrllatiol) tei~"~er~re in ~C.
Ep: Sinking point or processing temperature at 104dPa s in ~C.
Ew: Fusion point 10~ ~dPa s in ~C.
R: Specific electric resistance at 1550~C in Ohm cm.
v: Melting rate in mm/min.
Visk.: LogariU"" of the viscosity at 15~0~C in dPa s.
Na20 + K20 + CaO + MgO + BaO
Basicity module =
B203 + SiO2 + A1203 + ZrO2
21 939q9
E"~L)~li.,~ents (Nos. 1 to 4 and 20 for tG~ , ison)
No. SiO2 B203 A203 Na20 K~ CaO MgO BaO Z~2 Cl SK~2 8203
Z~02 R20
+ RO
1 80.40 13.0 2.25 3.7Q 0.55 0.02 0.01 0.03 0.05 80.43 17.28
2 79.80 12.40 3.00 4.20 0.~6 0.01 0.05 0.55 80.35 17.323 79.00 11.00 3.75 4.g5 0.80 0.01 0.05 0.85 0.05 78.85 16.81
4 78.90 10.65 4.10 4.45 1.40 0.01 0.05 0.85 0.05 79.75 16.56
77.50 11.93 3.77 5.06 0.83 0.05 0.86 0.06 78.36 17.87
6 77.?0 11.00 4.10 5.20 0.90 0.01 0.05 0.90 0.08 78.60 17.16
7 77.60 11.00 4.25 5.20 0.091 0.01 0.05 0.90 0.09 78.50 17.17
8 76.~0 11.30 4.37 5.45 0.92 0.02 0.01 0.92 0.10 77.82 17.70
3 76.60 11.3g 4.40 5.58 0.95 0.02 0.02 0.93 0.07 77.53 17.90
76.~0 11.44 4.25 5.25 1.05 0.02 0.05 0.91 0.10 77.81 17.81
11 76.90 11.58 4.15 5.22 1.06 0.05 0.01 0.89 0.09 77.79 17.79
12 76.60 11.00 4.25 5.20 0.91 0.01 0.05 1.90 0.10 78.50 17.17
13 77.10 11.~4 4.15 5.30 0.30 0.05 0.05 0.80 0.~3 0.10 77.73 18.11
14 77.00 11.89 4.21 5.45 0.40 0.01 0.01 0.63 0.10 77.63 17.7B
79.~3 12.00 4.25 5.45 0.83 0.02 0.02 0.80 0.10 77.43 18.32
16 77.46 10.eO 4.80 5.25 0.75 0.02 0.02 090 0.1C 78.36 16.8417 76.65 12.20 4.30 5.70 0.40 0.Q2 0.02 0.70 0.10 77.36 18.34
18 76.69 11.90 4.25 5.t2 1.40 0.02 0.02 0.50 0.10 77.29 18.46
1~ 76.~0 11.20 4.15 5.06 0.95 0.02 0.02 2.00 0.10 78.B0 17.25
75.32 12.20 3.68 5.~8 0.01 0.07 0.01 1.01 1.10 0.12 76.42 19.28
l~lo. 14 ~ nally 0.40% CeO No. 20 ~1- Iiti~nally 0.33% CeO.
No. R20 RO RO Ba~ ~lpha Tg Ew Ep R \~sk. v
+ RO Z~3 ~y
mod~
ule
1 4.28 0.03 1.00 0.045 3.30 535 815 1245 32.0 2.7 0.42
2 4.92 0.06 0.11 0.061 3.63 559 825 1234
3 5.81 0.06 0.07 0.062 3.90 557 1233 26.2 0.36
4 5.91 0.06 0.07 0.063 3.85 559 1245
5.94 0.05 0.06 0.063 4.07 567 815 1231 25.8 2.65 0.36
6 6.16 0.06 0.07 0.066 4.18 570 818 1228 25.0 2.65
7 6.17 0.06 0.07 0.066 4.18 56g 820 1228 25.0 2.65 0.39
8 6.40 0.03 0.03 0.068 4.30 566 809 1222 23.6 2.65 0.38
9 6.57 0.04 0.04 0.070 4.33 807 1219 23.2 2.65 0.47
6.37 0.07 0.08 0.068 4.26 571 813 1227 24.0 2.65 0.44
11 6.34 0.06 0.07 0.068 4.27 1227 24.0 2.65 0.43
12 6.17 0.06 0.03 0.066 4.12 554 1228
13 6.50 0.90 1.43 0.070 4.00 553 1226
14 5.87 0.02 0.03 0.063 4.05 552 1222
6.32 0.04 0.05 0.067 4.1g 552 1222
16 6.04 0.04 0.04 0.064 4.07 555 1227
17 6.14 0.04 0.06 0.065 4.16 551 1217
18 6.56 0.04 0.07 0.070 4.22 553 1230
19 6.05 0.04 0.02 0.064 4.06 555 1218
7.08 1.09 0.99 0.077 4.25 540 799 1176 13.6 2.45 0.54
