JPS59144620A - Partially stabilized zirconia fiber - Google Patents

Abstract

PURPOSE:The titled flexible and easily handleable fibers, containing zirconia and further magnesia, calcia, titania, indium oxide and rare earth element oxide in a specific proportion, and having a specific amount or more of fine particulate cubic crystallites. CONSTITUTION:Fibers, containing ZrO2 and further one or more of the following oxides in amount within the ranges expressed in terms of mol%; 0.1<=MgO<= 14; 0.1<=CaO<=12; 0.05<=TiO2<=20; 0.05<=In2O3<=15; 0.05<=Sc2O3<=15; 0.05<=Y2O3<= 4; 0.05<=La2O3<=30; 0.05<=CeO2<=25; 0.05<=Pr6O11<=20; 0.05<=Nd2O3<=15; 0.05<= Sm2O3<=15; 0.05<=Eu2O3<=15; 0.05<=Gd2O3<=15; 0.05<=Tb4O7<=15; 0.05<=Dy2O3<=15; 0.05<=Ho2O3<=15; 0.05<=Er2O3<=15; 0.05<=Tm2O3<=15; 0.05<=Yb2O3<=15; 0.05<= Lu2O3<=15; and having 10wt% or more cubic crystallites having <=2mu size.

Description

[Detailed description of the invention] The present invention relates to partially stabilized zirconia fibers.

Zirconia ceramic has excellent properties such as heat resistance and corrosion resistance that are unrivaled by other ceramics. But ioo.

Because the phase transition between monoclinic and tetragonal occurs at temperatures around ~1200°C, it is difficult to produce ceramics with a single composition of zirconia (monoclinic at low temperatures below 1000-1200°C), and It was a difficult material to handle due to limited availability.

However, by adding magnesia, calcia, rare earth elements, etc. to zirconia, stabilized zirconia and cubic crystals can be created that prevent the above phase transition from IFL as a fluorite-type cubic crystal which has a constant state of high temperature. Partially stabilized zirconia, which partially retains the phase transition described above, was developed as a mixture with monoclinic crystals, and the culm that is difficult to handle due to the phase transition has been overcome.

However, since such stabilized or externally stabilized zirconia has the above-mentioned chemical composition and crystal structure M, it has properties that are expected to be inherent in pure zirconia. The reality is that it is very difficult to be ltl~.

Proposals have been made to produce Ichinote, zirconia and dragon fibers using this method, and attempts have been made to commercialize them, but good fibers have not yet been produced. The reason for this is the above-mentioned Kinan thinking in the development of stabilized or partially stabilized zirconia ceramics (it can be said that proposals have only been made in the form of IA). For example, , (Jsp3992498 focuses only on the point that the phase change is 1, and adds magnesium, calcium, and a clay compound as a chemical agent.
Verification 1 for Ill's 1st year purchase is (1-1).Cubic zirconia (or stabilized zirconia) or cubic zirconia formed by adding mag, calcia, ittria, and nrica. Each i as a zirconia phase
l', fibers partially composed of zirconia (U.S.
p3311481), cubic stabilized zirconia with square sea bream, nua, and calcia
865, 1986-9896) is known,
Conventional stabilization or? It's amazing how far the idea of f15 O-stabilized zirconia ceramics has gone.

Therefore, the above-mentioned zirconia fibers are brittle against external mechanical forces, and are difficult to handle when they are still in the form of fibers.

The present invention has been made in light of the above, and is
The aim is to provide partially stabilized zirconia fibers that are flexible and easy to handle as fibers.

The present inventors conducted studies focusing on the chemical composition and microstructure of l/j and hawk fibers, and as a result, the present invention was completed.

That is, the partially stabilized zirconia-based powder of the present invention contains, in addition to zirconia, at least one of magnesia, calcia, titania, modified indium, and rare earth oxides in the following chemical composition range 4, and The chemical silk described in the above is characterized by having 10% or more of tetragonal crystallites with a diameter of 2 μm or less, rr'Q ・H+j,
11111rJ-4=# Medium K person ma, hru; Assuming that the lending body of the compound is 100 moles, the molar salary is () 1 ≦ presentation yato, i ≦ '0' = 1 4, 0
．． 1:'Q Ca0S 12 .

0.05'; TiO2S 20 , 0.05SI
n203415.

0 ()5≦SC2Q3ku, 15, 0.
05≦, Y2O3<~4.

005SLa-ro3;”=30+0.055
Ce02:525 +005≦, Pr60I Is
20 + 0.05<, Nd2O3', y-15r
o, 05″′−, Sm20s′l′;, 15 +
0.05<, Eu203-15 +0.05-1000'=
Gd 20sS, 1 5'+0.
05 ':', T +), o 7 2〉 15.

o, oa = D7203 S 15 + 0.05
'> Ho203m 15 +005, Er203
≦-, 15, o, os\ 'Cing m2o3', :':'y
1 5 +0.05;i Yb20s S 1
5, 0.05 riLu2O3$15.

! +:I″:The sunken wood plug h- of partial stabilization of zirconia in the past is a mixture of firefly Ni)Qj cubic crystal (stabilized zirconia) and cholinic crystal (unstabilized zirconia) (
By making stabilized zirconia, we aim to extend the lifespan of stabilized zirconia by not causing the 11 transition from 6. It's something to do.

On the other hand, the part 'M'if-zirconia of the present invention is a metastable tetragonal crystal (°C) that necessarily turns blue at room temperature, and this tetragonal crystallite is caused by stress, jrM
It transforms into a monoclinic phase, which is a stable phase at room temperature, by an external mechanical force such as . Therefore, (, if partially stabilized zirconia is an essential constituent phase of the fluorite-type cubic JAlk
The idea of sinking is a fundamental VC problem.

, + Partially stabilized zirconia purchase J ((t,
The chemical composition of the beak compound &['i, the surrounding area and the microstructure of the set of fibers were determined as described above for the reasons listed below.

1,...) The chemical composition of the evening sun is mutually related to the microstructure of the fiber, and if it falls outside the above range, 1. "It is not possible to form more than 10 square crystallites of 2 μm or less in the J male. In other words, MyO, CaO in the fiber
are respectively 01 mol 740 sides 1 go and TiO□,
When the amount of the n20s + rare earth element nitride is less than 0.05 molti, hardly any IF square is formed in the M&fiber, and minor or peroclinic and cubic crystals are likely to be formed. On the other hand, each oxide in the value fiber exceeded the upper limit mentioned above. During the synthesis, cubic crystals are formed as the main phase and the crystal becomes opaque. The present invention does not contain pure zirconia or fibers.

In addition, the externally stabilized zirconia steel fiber of the present invention has tetragonal crystallites as an essential constituent phase, and the size of the crystallites is determined by the rolling method.
Due to differences in chemical composition, etc., it can become a stone, but it exists only at a thickness of less than 2 μm and is not a problem. This is because the tetragonal crystallites under formation are stable at room temperature and are in a state of free energy and energy that is better than stable monoclinic crystals, so shape factors such as the energy difference field + fti energy etc. It must be kept in the form of 1 part, smaller than in large chunks,
This is because it is more energetically advantageous to exist in a forgiven state.

In the mouth, it is necessary for these tetragonal crystallites to be absorbed by 1% or more during the formation of these tetragonal crystallites. In case,
It turns into powder without retaining its form. This phenomenon is caused by the fact that when an external force is applied to the hawk fiber, the metastable tetragonal crystallite transforms into a stable crystallite and absorbs the external mechanical force. is xo3. @: It is considered that if it becomes less than bone mass, it cannot absorb the external mechanical force.

As described above, the chemical composition of the fiber and the fine JM structure are inseparable in constructing the partially stabilized zirconia fiber of the present invention, and even if one or the other is satisfied, it will not be flexible. It is not possible to obtain one precept that is easy to handle.

In addition, in the present invention, 1. Or the tetragonal crystal in Ayana is 100.1
1 has no cooling support at all. Such a tetragonal crystal is ioo
* = % is in a simple sense (although it cannot be said to be partially stabilized, in this application, it is conveniently referred to as externally stabilized zirconia).
It is called W 41 fiber.

In the present invention, the parts other than tetragonal crystallites, which are essential constituent phases constituting the fiber, are regular shaped, cubic crystallites, monoclinic crystallites, or two of these three gods (i of 1 or more, It is in a state where 11 is combined.

The zirconia content in Alil+ is made up of 10 moles of hafnia derived from the raw material.
(It doesn't support it even if it goes up.)

Partially stabilized zirconia of the present invention ′w ”+& :+jj
The so-called thermal 11Vt method is used as a method for producing . This chisel method includes (+) ij] Preparation of spinning solution (spinning solution), (11) Dry spinning, (iii) Heat component I・a, Ov) Crystallization process "'118" A: This method is easy to remove the spinning solution, which has poor spinnability, and also incorporates conventional technology. By the way, it is 11 years old in that it is possible to form the IE square zirconia into the bow during the precepts. 1, bottom - Regarding each of the above-mentioned bows: aq: I will explain to in+.

(1) Cooked in the same manner as in the 1 night (1-1) period.

That is, by mixing and dissolving at least a zirconium compound and a compound of V + y, Ca, 'ri, In or 4, 1' elements in water or organic solvent,
If the process is carried out, θ is prepared, ゛3 fibers are made, 71 fibers b] are adjusted to 2,000 ml, and a spinning solution (spinning solution) is obtained.

As the S bath medium, alcohol,
Ketones, amide types, etc. have been used for some time.

However, as r+'lJ convex zirconium compounds, (a) inorganic zirconium compounds such as salt salts, nitrate salts, zirconium tetrachloride, and (b) vinegar salts, salt salts, tetrabenzyl zirconium, etc. Organic zirconium compounds can be mentioned, and at least one of these is used.

Further, the compound of Mg + Ca + Ti, In or rare earth elements may be an organic compound or an organic compound, and at least one of these is used.

In order to improve the spinnability and stability of the solution, hydrochloric acid, (IdC acid, etc.), formic acid, organic acid, organic polymer compound, alcohol, i J+!j, ketone, ether, ester, if! 1I
Acid, surfactant, etc. may be added at the 114th point.

In this solution, add a powder of oxide or hydroxide of rare earth oxide or hydroxide to this solution.
You can talk. The crystallite diameter of these powders is likely to be less than 2 μrn J. The history includes the gas phase method, the Satoshi decomposition method,
Preferably, the particles are submicron particles produced by a coprecipitation method or the like. In particular, zirconia powder (amorphous or low-temperature crystallized submicron particles) is preferred.

The drying time of the solution prepared as described above varies depending on the composition or patterning method, but it is desirable that the number of voids be approximately 0.1 to 10,000. In general, the spinning operation will be more convenient if the viscosity of the solution is set higher in the case of spinning, i% continuous, 1 fiber, and lower in the case of short 1 fiber. In this case, it is not necessarily necessary that the amount of solid content absorbed into the viscous solution after the crystallization heat treatment is large, but rather it is preferable to emphasize the spinning properties.

(11) The J-spinning dry solution (spinning solution) prepared as described above is spun into continuous fake fibers or Chiiso fibers, which are front and center fibers, by dry spinning.

++! ! For example, a conventional winding method may be used to form a continuous fiber. In this winding method, the tip is 0.
The spinning solution is put into a container equipped with a spinning nozzle having a diameter of about 05 to 0.5 +a, and the spinning solution is pushed downward using compressed gas or a gear pump to achieve warm and wet coagulation (N)4. A thin stream of the spinning solution is formed in the surrounding air, and the spinning solution is dropped onto a rotating cylindrical drum while evaporating the solvent, and the continuous fiber is wound around the cylindrical drum.

In addition to the winding method, as mentioned above, it is possible to converge the trickle pushed out into an atmosphere with controlled temperature and humidity in the thread path,
The continuous fibers are once received by a rotating cylindrical drum placed below the iron fibers, and then drawn between two cylindrical drums placed below the iron fibers rotating in opposite directions. It is also possible to collect the rice on a belt conveyor that moves while vibrating left and right in the reverse direction. Further, the above-mentioned stretching operation can be performed not by using a rotating drum but also by using a laminar air flow.

The diameter of the continuous fiber spun in this way is 1 to 10.
0/Im.

On the other hand, short and long fibers can be made by cutting the above-mentioned continuous fibers into appropriate lengths, but they can also be made by, for example, the method described below.

That is, the spinning solution is put into a rotating cylinder that cures a pore of 0.1 to 1 tll in circumference IJ1, and this cylinder is rotated at a high pitch, and the centrifugal force causes the spinning solution to be heated through the #tll hole. It is possible to create a short-term storage tank by ejecting it into a humidity-controlled atmosphere. During this gap, an air jet is formed on the outer periphery of the rotating cylinder, and the +IN output of the spinning solution is blown out.
You can create short mercenary fibers with smaller bonds.

It's a virtue, I'm sorry for the temperature and humidity, and I'm sorry for making 44 tons in 1 listing.
It is also possible to create a short-cut fabric by blowing away the separation of the spinning solution formed in the surrounding air with an air jet.

The short fibers produced in this way are
l・The diameter of the spool is ~1 minute smaller, about 0.5~100μ
It becomes +71.

(:ii) After sufficiently drying the precursor fiber produced as described above to remove the remaining solvent, the compound in the precursor fiber is decomposed by VD heat to obtain a zirconia fiber.

The above decomposition temperature varies depending on the compound and the firing atmosphere, but in a non-oxidizing atmosphere such as air, carbon dioxide gas, or water vapor (also a hydrolyzable atmosphere), vinegar and acid compounds will react at about 400°C and chlorine. The compound is heat treated at about 600°C. In general, the decomposition temperature is low in the case of organic compounds, and the decomposition temperature is high in the case of front-rut compounds. In addition, heating the precursor fibers containing organic compounds in a non-oxidizing atmosphere, such as nitrogen, argon, helium, hydrogen, ammonia, or -carbon monoxide, produces carbon-containing zirconia'.
Masazuke Gawei is talented outside the country.

When analyzed by X-ray diffraction, the zirconia fibers subjected to the step 1 are WIJf, which shows a broad peak with no distinct nlf or crystalline shape.

By applying heat treatment to Gy), the tetragonal crystallites under 2μat D) can be made into partially stabilized zirconia with more than 10 folds.

In some cases, this crystallization heat treatment can be performed in the same furnace following the heat treatment in (iii) above, but in order to obtain good fibers, the power and heat conditions in (iii) above are [hi, temperature rise rate 1 aspect, atmosphere circle] Qi temples are often different,
It is preferable to once take out the fibers from the pyrolysis furnace and transfer them to another furnace dedicated to crystallization for heat treatment.

As such a crystallization heat treatment, for example, (a) a low-temperature heat treatment method or (b) a high-temperature heat treatment method can be used.

The low-temperature heat treatment method of (a) heats the amorphous fiber after heat content 11a at a low temperature, and then heats the fiber at a low temperature to form the lower parts jl, s, jf.
, which forms a square crystal. This'; 11 go, the best as a crystal? The low-temperature hexagonal crystals that occur in JJ are transformed into mesoclinic and cubic crystals, resulting in 10 tons of crystals.
Therefore, be careful not to apply excessive heat treatment.

When the high-density structure of Z
After heating sufficiently at a height of 17g, -) above 1900'C for a stratified layer having a composition of 0293 mol of r0 and 7 mol of CaO, it was rapidly cooled and/or the whole was frozen as a high-temperature cubic crystal. Furthermore, the tetragonal crystal is aged by stable temperature oxidation so that the number of tetragonal crystallites becomes 10 or more. After the above-mentioned rapid cooling and aging d1, the skin may be cooled down to a certain temperature, and then aged by heating at a humidity level where the tetragonal crystals are stable, or at a temperature range where the tetragonal crystals are stable. An aging method may be used instead of rapid cooling.

Such crystallization heat treatment can also be carried out in interbody air with +ψ-forming properties and metal-forming properties.

Therefore, the amorphous zirconia crystal containing the carbon of the JII heat treatment was heat-treated to crystallize it in two atmospheres to make it non-monalized, and then the charcoal and Schiff were formed. It is also possible to produce partially stabilized zirconia with the following tetragonal crystallites of 1011 or more, excluding carbon. At this time, it is desirable that carbon exists in a starved state.

Examples of the present invention will be explained below.

Examples 1 to 13 and Comparative Examples 1 to 14 First, the original interest 'd shown in Table 1 and '4%' Table 2
Using water as a solvent, the viscosity shown in the same table is obtained by using 7 thread-proofing liquids and 1 layer of 11 days (11 days). Elm: FffitJ
Spinning liquid having 10 circular nozzles with a total IG diameter of 0.1 1ill 1] Discharged from gold to form a fine θiL,
It was removed by winding it around a drum with a diameter of 18 rν and 1 calendar year while evaporating the water, which was a solvent. The word ``Saida,'' short, and ``juni'' means ``Ichihiki 4 Gokumetsudan.''[1] It was obtained by blowing away the other stream of Xun Shixin, which was formed in the same way as the 1st Go, with Airjinoet.

Subsequently, each precursor Shin-41 described in E was added to a sufficient amount of 1. I hire t
After s, φhorn ~ min 1・(
I did this. History 1. A crystallization active part t"1! was carried out to obtain zirconia 'n takata.

For each damaged zirconia vertebra, the following information is given: Alternative composition, microstructure, tetragonal crystallite size and:
Regarding the handling situation of li, L & li, see below! 3
Flying rescue; P, shown in 4 Jimo.

The chemical composition of Comparative Examples 1 to 14 for Comparative Examples 3 and 12 is within the range I:l of the present invention. However, if tetragonal crystals are not included, and for all other crystals, the composition is the 4+1 system of the present invention.
In addition to being outside, the tetragonal crystal is 4'i/) not t4 in 10. For this reason, the zirconia of Comparative Examples 1 to 14 is 1. All precepts are fragile, and there are some that turn into powder at the end of the admiration, and 1
．． lil! Treated as a loser V, my throat is always in trouble, 2ff
I sang it in j.

On the other hand, as is clear from Table 3 above, zirconia 'Iji',
All 6 pieces were "JI'j'i-resistant" and did not break at all.

In addition, in the above-mentioned 1-bite case and 1-bite case, Nd2O
3. Molecule F+(r-) on the cold earth element? ゛For sanded meat, Nd2O, (actual Jq example 10 and ratio 'I case 1
1], Sm203 (Example 13) r ErtOs
(Comparative Example 12), Yb20s (actual, Qfli Example 11
4.0 using Comparative Example 13) was representatively described, but it was confirmed that the same results as those described were obtained for other rare earth element oxidations having molecules of Nd2O3 or more.

As detailed above, according to the present invention, partially stabilized zirconia is used which is flexible and easy to use as a reconnaissance weapon.
It can provide an atmosphere.

Claims (1)

[Claims] Z
O$ 1:2 +0.05≦'ri02520
, 0.05:<In203515. 0.05%5c203≦15, 0.05SY20
, 54. 0.0!5'5Laz031"=30+0.0
5SCeO2425+005≦P r6o I + ≦
20 + 0.05'-5, ≧ d 20
32≦−015. 0.0558m? 0sS15, 0.05Sgu20
3≦15゜0.05≦c62o, ≦15, 0.05
";Tb4O7$15.0.0≦DY20+1≦15.0.05≦IJo203
≦15°0.05j-Fjr20sS15 + 0.
053Tmz○3≦15゜0.05SYbzOsSL5
, 0.05SLuzOsS15 lji IJl sinks, and tetragonal crystallites of 2 μm or less are IO double-layered.
Partially stabilized zirconia fiber characterized by having 9 or more.