JPH051955A - Heat history detecting molding - Google Patents
Heat history detecting moldingInfo
- Publication number
- JPH051955A JPH051955A JP3154893A JP15489391A JPH051955A JP H051955 A JPH051955 A JP H051955A JP 3154893 A JP3154893 A JP 3154893A JP 15489391 A JP15489391 A JP 15489391A JP H051955 A JPH051955 A JP H051955A
- Authority
- JP
- Japan
- Prior art keywords
- molded body
- temperature
- firing
- mgo
- heat history
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Landscapes
- Measuring Temperature Or Quantity Of Heat (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、セラミックスなどの焼
成工程における熱履歴を検知するためのものであり、特
にガラスセラミック、陶器、ステアタイト、釉薬焼き付
け等の、８００〜１３００℃の温度域の焼成における熱
履歴検知用成形体に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is for detecting the thermal history of ceramics in the firing process, particularly in the temperature range of 800 to 1300 ° C. such as glass ceramics, pottery, steatite, and glaze baking. The present invention relates to a molded body for detecting heat history during firing.
【０００２】[0002]
【従来の技術】セラミックスの焼成工程において、温度
プロファイル、焼成炉の種類、炉内のセッティング等に
よって被焼成体の受ける熱履歴は変化する。即ち、焼成
温度が同じでも他の条件が異なれば熱履歴は異なること
となり、この熱履歴を正しく検知する必要があった。2. Description of the Related Art In the firing process of ceramics, the thermal history of the body to be fired changes depending on the temperature profile, the type of firing furnace, the settings in the furnace, and the like. That is, even if the firing temperature is the same, the thermal history will be different if other conditions are different, and it is necessary to correctly detect this thermal history.
【０００３】例えば、実開昭５６−２９４４１号公報な
どに示されているゼーゲルコーンを用いて被焼成体の熱
履歴を検知することが行われていた。ゼーゲルコーンと
は、溶倒温度の異なる複数の三角錐状体を支持台上に備
えたものであり、このゼーゲルコーンを被焼成体と共に
焼成した後、各三角錐状体の倒れ方によって、熱履歴を
検知するようになっていた。しかし、これでは正確な検
知ができないことから、現在では使用されることが少な
くなっている。For example, the thermal history of a body to be fired has been detected using a Zegel cone as disclosed in Japanese Utility Model Laid-Open No. 56-29441. Zegel cones are provided with a plurality of triangular pyramids having different melting temperatures on a support, and after firing this Zegel cone together with the body to be fired, the thermal history of the triangular pyramids falls, It was supposed to detect. However, since it cannot detect accurately, it is now less used.
【０００４】そこで、例えば特開平１−１８４３８８号
公報等に示されているように、セラミックスの未焼成成
形体を用いて、この成形体を被焼成体と共に焼成した
後、収縮による寸法変化を測定することによって、熱履
歴を検知することが行われていた。例えば、図３に示す
ようなリング状の成形体２０、あるいは図４に示すよう
なシート状の成形体３０が用いられていた。Therefore, as disclosed in, for example, Japanese Unexamined Patent Publication (Kokai) No. 1-184388, an unsintered compact of ceramics is used, and this compact is fired together with the body to be sintered, and then the dimensional change due to shrinkage is measured. By doing so, the thermal history was detected. For example, a ring-shaped molded body 20 as shown in FIG. 3 or a sheet-shaped molded body 30 as shown in FIG. 4 was used.
【０００５】なお、このような焼成収縮による寸法変化
を測定する場合、寸法変化は便宜的に温度に変換される
が、この温度は実温を測定したものではなく、熱履歴を
表すものであって、本発明では指示温度と呼ぶこととす
る。When measuring such a dimensional change due to firing shrinkage, the dimensional change is conveniently converted into a temperature, but this temperature does not represent an actual temperature but represents a thermal history. Therefore, in the present invention, it is referred to as an instruction temperature.
【０００６】[0006]
【発明が解決しようとする課題】ところが、上記の熱履
歴検知用セラミックス成形体は、Ａｌ2 Ｏ3 −Ｓｉ
Ｏ2 、またはＳｉＯ2 −ＭｇＯ系を主成分とし、多量の
不純物を含む天然原料からなるものであったため、焼成
収縮率にバラツキがあり、検知された指示温度の精度が
悪かった。また、１１００℃以下の比較的低温の焼成で
は、収縮しないために利用できないという問題点があっ
た。However, the above-mentioned ceramic molded body for thermal history detection has a problem of Al 2 O 3 --Si.
Since it was made of a natural raw material containing O 2 or SiO 2 —MgO system as a main component and containing a large amount of impurities, the firing shrinkage ratio varied, and the accuracy of the detected indicated temperature was poor. In addition, there is a problem that it cannot be used in firing at a relatively low temperature of 1100 ° C. or less because it does not shrink.
【０００７】さらに、図２に示すリング状のものでは、
面積が大きいため、焼成炉内で広いスペースを必要と
し、図３に示すシート状のものでは、ソリが発生して正
しく寸法を測定できないなどの問題点があった。Further, in the ring shape shown in FIG.
Since the area is large, a large space is required in the firing furnace, and the sheet-like material shown in FIG. 3 has a problem that warpage occurs and the dimension cannot be measured correctly.
【０００８】[0008]
【課題を解決するための手段】そこで本発明は、ＳｉＯ
2 −ＭｇＯ−ＣａＯの三成分組成図におけるＳｉＯ2 ４
０〜６５重量％、ＭｇＯ０〜２５重量％、ＣａＯ１０〜
６０重量％の範囲内の組成をもったセラミックス未焼成
成形体を熱履歴検知用成形体としたものである。Therefore, according to the present invention, the SiO 2
SiO 2 4 in the three-component composition diagram of 2- MgO-CaO
0-65 wt%, MgO 0-25 wt%, CaO10
A ceramic unfired molded body having a composition within the range of 60% by weight was used as a thermal history detection molded body.
【０００９】本発明において、ＳｉＯ2 を４０〜６５重
量％としたのは、ＳｉＯ2 が６５重量％より多いか、４
０重量％より少ない場合は１３００℃でほとんど収縮し
ないためである。また、ＭｇＯを０〜２５重量％とした
のは、ＭｇＯが２５重量％より多いと１３００℃でほと
んど収縮しないためである。なお、本発明においてＭｇ
Ｏは必須成分ではないが、好ましくは５〜２５重量％の
範囲で含んでいた方がよい。そして、残部が１０〜６０
重量％のＣａＯからなっているが、この他の成分を微量
に含んでいてもよい。また、上記ＳｉＯ2 、ＭｇＯ、Ｃ
ａＯは、酸化物だけでなく、水酸化物、炭酸塩などの化
合物の形でもよい。In the present invention, the SiO 2 content of 40 to 65% by weight means that the SiO 2 content is more than 65% by weight or 4
This is because when the content is less than 0% by weight, the material hardly shrinks at 1300 ° C. Moreover, the reason why the content of MgO is 0 to 25% by weight is that if the content of MgO is more than 25% by weight, there is almost no shrinkage at 1300 ° C. In the present invention, Mg
O is not an essential component, but it is preferable to contain O in the range of 5 to 25% by weight. And the balance is 10-60
Although it is composed of CaO in weight%, it may contain a small amount of other components. In addition, the above-mentioned SiO 2 , MgO, C
aO may be in the form of a compound such as a hydroxide or a carbonate, as well as an oxide.
【００１０】[0010]
【実施例】以下本発明の実施例を説明する。EXAMPLES Examples of the present invention will be described below.
【００１１】図１（ａ）（ｂ）に示すように、本発明の
熱履歴検知用成形体１０は、円板体に平行な弦部１２、
１２を形成したものであり、残された円弧部は優れた真
円度の測定面１１、１１としてある。また、表裏を区別
するためのドットあるいはアルファベットなどの刻印に
よる凹部１３が片面に形成され、上下面の角部には面取
り１４が施されている。As shown in FIGS. 1 (a) and 1 (b), the thermal history detecting molded body 10 of the present invention comprises a chord portion 12 parallel to the disc body.
12 is formed, and the remaining circular arc portions are the measurement surfaces 11 and 11 having excellent roundness. Further, a concave portion 13 is formed on one surface by marking such as dots or alphabets for distinguishing the front side and the back side, and chamfers 14 are provided at upper and lower corners.
【００１２】さらに、この成形体１０は、図２のＳｉＯ
2 −ＭｇＯ−ＣａＯ三成分組成図に示すように、ＳｉＯ
2 ４０〜６５重量％、ＭｇＯ０〜２５重量％、ＣａＯ１
０〜６０重量％の範囲内の組成からなっており、原料粉
末の粒系、成形体の生密度などを極めて厳密に管理し、
プレス成形してなる、未焼成成形体である。そして、後
述するように、ある条件の下で焼成温度を変化させて、
この成形体１０の焼成後の寸法を測定し、寸法と焼成温
度の関係を換算表として用意しておく。その後、異なる
条件で焼成を行う際に、被焼成体と共にこの成形体１０
を焼成し、焼成後の寸法変化を測定することによって、
上記換算表より指示温度を求めることができる。Further, the molded body 10 is made of SiO 2 shown in FIG.
2- MgO-CaO As shown in the three-component composition diagram, SiO
2 40-65% by weight, MgO 0-25% by weight, CaO1
It has a composition within the range of 0 to 60% by weight, and controls the grain system of the raw material powder, the green density of the molded body, and the like very strictly,
It is an unsintered compact formed by press molding. Then, as will be described later, by changing the firing temperature under certain conditions,
The dimensions of the molded body 10 after firing are measured, and the relationship between the dimensions and the firing temperature is prepared as a conversion table. After that, when firing is performed under different conditions, the molded body 10 is sintered together with the body to be fired.
By firing and measuring the dimensional change after firing,
The indicated temperature can be obtained from the conversion table.
【００１３】なお、前記したように、この指示温度と
は、実際の温度ではなく、熱履歴を便宜的に表したもの
である。即ち、本発明の熱履歴検知用成形体を用いれ
ば、焼成条件が異なる場合でも、指示温度を求めること
によって、熱履歴自体を管理することが可能となる。As described above, the indicated temperature is not an actual temperature but a thermal history for convenience. That is, by using the heat history detecting molded body of the present invention, it is possible to manage the heat history itself by obtaining the indicated temperature even when the firing conditions are different.
【００１４】また、本発明の成形体は、さまざまな焼成
雰囲気の下で使用できるが、被酸化性雰囲気で使用する
場合は、仮焼して脱バインダーを行った方がよい。The molded article of the present invention can be used in various firing atmospheres, but when used in an oxidizable atmosphere, it is better to perform calcination to remove the binder.
【００１５】さらに、本発明の成形体１０は、弦部１
２、１２をもっていることから、図２に示した従来例に
比べて面積が小さく、焼成炉内で大きなスペースを必要
としない。なお、この弦部１２、１２は互いに平行でな
くてもよく、一ヶ所のみに形成してもよい。さらに、本
発明の成形体１０は、３〜１０ｍｍ程度の肉厚をもった
プレス成形品であるからソリなどが生じることはなく、
また寸法測定時には図１（ａ）に示すように、円弧をし
た測定面１１、１１間を低定圧マイクロメータで測定す
ればよく、測定位置がずれても同じ直径Ｄを正確に測定
できる。Further, the molded body 10 of the present invention comprises the chord portion 1
Since it has 2 and 12, it has a smaller area than the conventional example shown in FIG. 2 and does not require a large space in the firing furnace. The string portions 12 and 12 do not have to be parallel to each other, and may be formed at only one place. Furthermore, since the molded product 10 of the present invention is a press-molded product having a wall thickness of about 3 to 10 mm, warpage does not occur,
Further, at the time of dimension measurement, as shown in FIG. 1A, a low constant pressure micrometer may be used to measure between the arcuate measurement surfaces 11, 11 and the same diameter D can be accurately measured even if the measurement position is deviated.
【００１６】また、本発明の成形体１０の形状について
は、密度が均一となるような単純な形状であれば、さま
ざまなものとすることができる。Further, the shape of the molded body 10 of the present invention can be various as long as it is a simple shape having a uniform density.
【００１７】実施例１ 精製したＳｉＯ2 、ＭｇＯ、ＣａＯ原料を使用して表１
および図２に示す組成とし、アルミナボールにより湿式
粉砕し、レーザー光散乱法による粒度分析を行って、平
均粒径２．０±０．１μｍの範囲とする。この原料粉末
に６重量％のワックス系バインダーを添加混合し、噴霧
乾燥することによって、流動性の良い顆粒を得る。この
顆粒を、空調された成形室にて、図１（ａ）（ｂ）に示
す形状にプレス成形するが、このとき成形体の生密度を
１．９００±０．００５ｇ／ｃｍ3 の範囲内として、本
発明の熱履歴検知用成形体を得た。 Example 1 Using purified SiO 2 , MgO and CaO raw materials, Table 1
And the composition shown in FIG. 2 is wet pulverized with an alumina ball, and a particle size analysis is carried out by a laser light scattering method to obtain an average particle size of 2.0 ± 0.1 μm. A 6 wt% wax-based binder is added to and mixed with the raw material powder, and spray-dried to obtain granules having good fluidity. The granules are press-molded in an air-conditioned molding chamber into the shape shown in FIGS. 1 (a) and 1 (b). At this time, the green density of the molded body is within the range of 1.900 ± 0.005 g / cm 3 . As a result, a molded article for heat history detection of the present invention was obtained.
【００１８】これらの成形体を、８００℃で２時間、１
０００℃で２時間、１３００℃で２時間の３種類の条件
で焼成した。結果は表２に示す通りである。These molded bodies were heated at 800 ° C. for 2 hours, and 1
Firing was performed under three kinds of conditions of 000 ° C. for 2 hours and 1300 ° C. for 2 hours. The results are shown in Table 2.
【００１９】[0019]
【表１】 [Table 1]
【００２０】[0020]
【表２】 [Table 2]
【００２１】表１、表２より明らかに、ＳｉＯ2 が６５
重量％を超えたＮｏ．７、４０重量％未満のＮｏ．９、
ＭｇＯが２５重量％を超えたＮｏ．８は、１０００℃で
はほとんど収縮せず、１３００℃でもわずかに収縮する
程度であるため、目的とする温度範囲での使用には適さ
なかった。Clearly from Tables 1 and 2, the SiO 2 content is 65.
No. which exceeded the weight%. No. 7, less than 40% by weight. 9,
No. in which MgO exceeded 25% by weight. No. 8 was not suitable for use in the intended temperature range because it hardly shrinks at 1000 ° C and slightly shrinks at 1300 ° C.
【００２２】これに対し、Ｎｏ．１〜６の本発明実施例
では、その収縮過程が８００〜１３００℃の範囲内にあ
ることがわかった。例えば、Ｎｏ．１は８００〜１００
０℃、Ｎｏ．４は９００〜１１５０℃の温度範囲におい
て適している。On the other hand, in No. In Examples 1 to 6 of the present invention, it was found that the shrinking process was in the range of 800 to 1300 ° C. For example, No. 1 is 800-100
0 ° C, No. 4 is suitable in the temperature range of 900 to 1150 ° C.
【００２３】実験例２ 実験例１と全く同様にして、表１中Ｎｏ．４の組成で、
直径Ｄが２２．３００ｍｍの熱履歴検知用成形体１０を
用意した。この成形体１０を厳密に管理校正された焼成
炉を用いて、酸化雰囲気にて、昇温速度２００℃／時、
最高焼成温度で２時間保持、降温速度３００℃／時とし
て焼成し、３５０℃で１時間脱脂した。焼成後の成形体
１０の寸法を、２０℃にて低定圧マイクロメータで測定
した。 Experimental Example 2 In the same manner as in Experimental Example 1, No. 1 in Table 1 was used. With the composition of 4,
A heat history detecting molded body 10 having a diameter D of 22.300 mm was prepared. This molded body 10 was heated in an oxidizing atmosphere at a temperature rising rate of 200 ° C./hour using a firing furnace that was rigorously controlled and calibrated.
It was held at the maximum firing temperature for 2 hours, fired at a temperature lowering rate of 300 ° C./hour, and degreased at 350 ° C. for 1 hour. The dimensions of the molded body 10 after firing were measured at 20 ° C. with a low constant pressure micrometer.
【００２４】焼成温度（指示温度）をさまざまに変化さ
せて、それぞれ２０個の成形体１０の焼成の焼成を３回
繰り返して行った。この結果は、表３および図５に示す
通りである。The firing temperature (instructed temperature) was variously changed, and the firing of 20 molded bodies 10 was repeated three times. The results are shown in Table 3 and FIG.
【００２５】また、各温度における、寸法のばらつき
（３σ）と、その温度での１℃当たりの寸法変化量（接
線の傾き）から、指示温度の検知精度＝±寸法のばらつ
き／１℃当たりの寸法変化量により、指示温度の検知精
度（３σ）を算出した。結果は、表３に示す通り、９０
０〜１１５０℃の範囲内で、指示温度の検知精度を±２
℃以内とすることができた。Further, from the dimensional variation (3σ) at each temperature and the dimensional change amount (tangent slope) per 1 ° C. at that temperature, the detection accuracy of the indicated temperature = ± dimensional variation / per 1 ° C. The detection accuracy (3σ) of the indicated temperature was calculated from the dimensional change amount. The results are 90 as shown in Table 3.
Within the range of 0 to 1150 ℃, the detection accuracy of the indicated temperature is ± 2
It could be kept within ℃.
【００２６】さらに、表３では指示温度５０℃ごとの成
形体の寸法を示しているが、もっと細かな指示温度ごと
の寸法を測定しておくことによって、成形体の寸法と指
示温度の換算表とすることができる。Further, although Table 3 shows the dimensions of the molded body for each indicated temperature of 50 ° C., a conversion table for the dimensions of the molded body and the indicated temperature can be obtained by measuring the dimensions for each of the more detailed indicated temperatures. Can be
【００２７】[0027]
【表３】 [Table 3]
【００２８】また、上記実施例では、熱履歴検知用成形
体１０を得るために、原料の粒径２．０±０．１μｍ、
成形体の生密度１．９００±０．００５ｇ／ｃｍ3 とし
たが、いずれもこの値に限定されるものではなく、さま
ざまに変化させることができる。通常、粒径については
±０．２μｍで管理し、生密度については±０．０１ｇ
／ｃｍ3 の範囲内にバラツキを押さえれば、指示温度の
検知精度を±２℃とすることが可能であった。Further, in the above embodiment, in order to obtain the heat history detecting molded body 10, the grain size of the raw material is 2.0 ± 0.1 μm,
The green density of the molded body was 1.900 ± 0.005 g / cm 3 , but the green density is not limited to this value and can be variously changed. Normally, the particle size is controlled at ± 0.2 μm, and the raw density is ± 0.01 g
By suppressing the variation within the range of / cm 3 , it was possible to make the detection accuracy of the indicated temperature ± 2 ° C.
【００２９】[0029]
【発明の効果】このように本発明によれば、ＳｉＯ2 −
ＭｇＯ−ＣａＯの三成分組成図におけるＳｉＯ2 ４０〜
６５重量％、ＭｇＯ０〜２５重量％、ＣａＯ１０〜６０
重量％の範囲内の組成をもったセラミックス未焼成成形
体を熱履歴検知用成形体としたことによって、指示温度
の測定精度を±２℃以内と極めて高精度にできることか
ら、焼成条件が変わっても焼成工程を厳密に管理するこ
とができ、優れた焼結体を得ることが可能となる。ま
た、特に１１００℃以下の比較的低温での焼成管理を可
能とすることができる。As described above, according to the present invention, SiO 2 −
In the three-component composition diagram of MgO-CaO, SiO 2 40-
65% by weight, MgO 0 to 25% by weight, CaO 10 to 60
By using a ceramic unfired molded body with a composition within the range of wt% as a thermal history detection molded body, the measurement accuracy of the indicated temperature can be made extremely accurate to within ± 2 ° C. Also, the firing process can be strictly controlled, and an excellent sintered body can be obtained. Further, it is possible to enable firing control at a relatively low temperature of 1100 ° C. or less.
【図１】（ａ）は本発明実施例の熱履歴検知用成形体を
示す平面図、（ｂ）は同図（ａ）中のＸ−Ｘ線断面図で
ある。FIG. 1A is a plan view showing a heat history detection molded body according to an embodiment of the present invention, and FIG. 1B is a sectional view taken along line XX in FIG. 1A.
【図２】本発明の熱履歴検知用成形体の組成範囲を示す
三成分組成図である。FIG. 2 is a three-component composition diagram showing the composition range of the molded article for heat history detection of the present invention.
【図３】従来の熱履歴検知用成形体を示す斜視図であ
る。FIG. 3 is a perspective view showing a conventional molded body for heat history detection.
【図４】従来の熱履歴検知用成形体を示す斜視図であ
る。FIG. 4 is a perspective view showing a conventional heat history detection molded body.
【図５】本発明の熱履歴検知用成形体における、焼成収
縮率と指示温度の関係を示すグラフである。FIG. 5 is a graph showing the relationship between the firing shrinkage ratio and the indicated temperature in the heat history detection molded body of the present invention.
１０・・・熱履歴検知用成形体 １１・・・測定面 １２・・・弦部 １３・・・凹部 １４・・・面取り 10 ... Mold for heat history detection 11 ... Measurement surface 12 ... Chord portion 13 ... Recessed portion 14 ... Chamfer
Claims (1)
におけるＳｉＯ2 ４０〜６５重量％、ＭｇＯ０〜２５重
量％、ＣａＯ１０〜６０重量％の範囲内の組成をもった
セラミックス未焼成成形体からなることを特徴とする熱
履歴検知用成形体。[Claims 1] SiO 2 40 to 65% by weight in the ternary composition diagram of SiO 2 -MgO-CaO, MgO0~25 wt%, with a composition within the range of CaO10~60 wt% A molded body for thermal history detection, comprising a ceramic unfired molded body.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3154893A JP2941495B2 (en) | 1991-06-26 | 1991-06-26 | Molded body for thermal history detection |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3154893A JP2941495B2 (en) | 1991-06-26 | 1991-06-26 | Molded body for thermal history detection |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH051955A true JPH051955A (en) | 1993-01-08 |
| JP2941495B2 JP2941495B2 (en) | 1999-08-25 |
Family
ID=15594261
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3154893A Expired - Lifetime JP2941495B2 (en) | 1991-06-26 | 1991-06-26 | Molded body for thermal history detection |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2941495B2 (en) |
-
1991
- 1991-06-26 JP JP3154893A patent/JP2941495B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JP2941495B2 (en) | 1999-08-25 |
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