JP2874057B2 - Silicon nitride powder - Google Patents
Silicon nitride powderInfo
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- JP2874057B2 JP2874057B2 JP23424190A JP23424190A JP2874057B2 JP 2874057 B2 JP2874057 B2 JP 2874057B2 JP 23424190 A JP23424190 A JP 23424190A JP 23424190 A JP23424190 A JP 23424190A JP 2874057 B2 JP2874057 B2 JP 2874057B2
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Description
【発明の詳細な説明】 産業上の利用分野 本発明は、優れた強度を有する焼結体を得ることがで
きる窒化ケイ素粉末に関する。Description: TECHNICAL FIELD The present invention relates to a silicon nitride powder capable of obtaining a sintered body having excellent strength.
従来の技術及び発明が解決しようとする課題 従来より、窒化ケイ素粉末を焼結して得られる窒化ケ
イ素焼結体については、高温強度材料として種々の用途
開発が進められており、高強度を有する焼結体を得るた
めに種々の研究が行われている。Conventional Techniques and Problems to be Solved by the Invention Conventionally, for silicon nitride sintered bodies obtained by sintering silicon nitride powder, various applications have been developed as high-temperature strength materials and have high strength. Various studies have been conducted to obtain a sintered body.
ここで、焼結原料である窒化ケイ素粉末の酸素含有量
が、得られた焼結体の強度に影響を及ぼすことが知られ
ており（セラミックス17（1982）No.10）、高強度の焼
結体を得るため酸素含有量を調整した窒化ケイ素粉末も
提案されている（特開平１−313308号公報）。Here, it is known that the oxygen content of the silicon nitride powder, which is a sintering raw material, affects the strength of the obtained sintered body (ceramics 17 (1982) No. 10). There has also been proposed a silicon nitride powder in which the oxygen content is adjusted to obtain a sintered body (Japanese Patent Application Laid-Open No. 1-3313308).
しかしながら、このような窒化ケイ素粉末の焼結体で
あっても、用途によっては強度が不十分な場合もあり、
更なる高強度化が望まれる。However, even with such a sintered body of silicon nitride powder, the strength may be insufficient depending on the application,
Further strengthening is desired.
本発明は、上記事情に鑑みなされたもので、優れた強
度を有する焼結体を得ることができる窒化ケイ素粉末を
提供することを目的とする。The present invention has been made in view of the above circumstances, and has as its object to provide a silicon nitride powder from which a sintered body having excellent strength can be obtained.
課題を解決するための手段及び作用 本発明者は、上記目的を達成するため鋭意検討を行な
った結果、酸素含有量が１重量％以下の金属ケイ素粉末
を用い窒素ガス雰囲気又は窒素を含む非酸化性ガス雰囲
気でこの雰囲気中の水分量をコントロールして、α分率
90％以上、BET比表面積10m2/g以上、平均粒子径0.6μｍ
以下の窒化ケイ素粉末の内部酸素量を0.5重量％未満に
制御することにより、非常に高強度の焼結体を得ること
ができる窒化ケイ素粉末とすることができることを見い
出した。Means and Action for Solving the Problems As a result of diligent studies to achieve the above object, the present inventor has found that a metal silicon powder having an oxygen content of 1% by weight or less is used and a nitrogen gas atmosphere or a non-oxidation containing nitrogen is used. Control the amount of water in this atmosphere in an inert gas atmosphere, and
90% or more, BET specific surface area 10m 2 / g or more, average particle diameter 0.6μm
It has been found that by controlling the internal oxygen content of the following silicon nitride powder to less than 0.5% by weight, it is possible to obtain a silicon nitride powder from which a very high-strength sintered body can be obtained.
即ち、従来より窒化ケイ素焼結体の特性、特に強度に
関しては上述したように原料粉末中の酸素含有量が影響
すると考えられているが、本発明者は、この原料粉末中
の酸素の存在形態に着目し、種々検討を重ねたところ、
その内部酸素含有量を0.5重量％未満に制御することが
焼結体の強度向上の点で極めて有効であり、特にα分率
90％以上,BET比表面積10m2/g以上，平均粒子径0.6μｍ
以下の直接法で得られる窒化ケイ素粉末において、その
内部酸素量を0.5重量％未満に制御し、更に好ましくは
外部酸素量を0.5重量％以下に制御することにより、こ
の窒化ケイ素粉末から顕著に高強度化された窒化ケイ素
焼結体が得られることを見い出したものである。That is, conventionally, it has been considered that the properties of the silicon nitride sintered body, particularly the strength, are influenced by the oxygen content in the raw material powder as described above. Focused on and after various studies,
Controlling the internal oxygen content to less than 0.5% by weight is extremely effective in improving the strength of the sintered body.
90% or more, BET specific surface area 10m 2 / g or more, average particle diameter 0.6μm
In the silicon nitride powder obtained by the following direct method, the internal oxygen content is controlled to less than 0.5% by weight, more preferably, the external oxygen content is controlled to 0.5% by weight or less, whereby the silicon nitride powder has a remarkably high content. It has been found that a strengthened silicon nitride sintered body can be obtained.
従って、本発明は、酸素含有量が１重量％以下の金属
ケイ素粉末を窒素ガス雰囲気又は窒素を含む非酸化性ガ
ス雰囲気でこの雰囲気中の水分量をコントロールするこ
とにより製造され、α分率が90％以上、BET比表面積が1
0m2/g以上、平均粒子径が0.6μｍ以下で、内部酸素含有
量が0.5重量％未満であることを特徴とする窒化ケイ素
粉末を提供する。Therefore, the present invention is manufactured by controlling the amount of water in a metal silicon powder having an oxygen content of 1% by weight or less in a nitrogen gas atmosphere or a non-oxidizing gas atmosphere containing nitrogen, and controlling the water content in the atmosphere. 90% or more, BET specific surface area is 1
Disclosed is a silicon nitride powder characterized by having an average particle diameter of not less than 0 m 2 / g, an average particle diameter of not more than 0.6 μm, and an internal oxygen content of less than 0.5% by weight.
ここで、窒化ケイ素粉末の内部酸素量を制御すること
は、上記特開平１−313308号公報においても開示されて
いるが、この公報の提案は表面（外部）酸素量を0.3〜
0.6重量％、内部酸素量を0.5〜1.0重量％とするもので
ある。しかし、後述する比較例に示したように、内部酸
素量が0.5重量％以上のものは、内部酸素の少ないもの
に比べて焼結体強度の点で劣るもので、窒化ケイ素粉末
の内部酸素量を0.5重量％未満にコントロールすること
により焼結体強度を高めるということは、本発明者によ
る新知見である。Here, the control of the internal oxygen content of the silicon nitride powder is also disclosed in the above-mentioned JP-A-1-313308, but the proposal in this publication proposes that the surface (external) oxygen content be reduced to 0.3 to 0.3.
0.6% by weight and the amount of internal oxygen is 0.5 to 1.0% by weight. However, as shown in the comparative examples described later, those having an internal oxygen content of 0.5% by weight or more are inferior in the strength of the sintered body as compared with those having a low internal oxygen, and the internal oxygen content of the silicon nitride powder is low. It is a new finding by the present inventors to increase the strength of the sintered body by controlling to less than 0.5% by weight.
以下、本発明につき更に詳しく説明する。 Hereinafter, the present invention will be described in more detail.
本発明の窒化ケイ素粉末は、上述のようにα分率が90
％以上、BET比表面積が10m2/g以上、好ましくは11〜15m
2/g、平均粒子径が0.6μｍ以下、好ましくは0.4〜0.6μ
ｍで、内部酸素含有量が0.5重量％未満、好ましくは0.2
重量％以上、0.5重量％未満のものであり、より好まし
くは外部酸素含有量が0.5重量％以下のものである。The silicon nitride powder of the present invention has an α fraction of 90 as described above.
% Or more, BET specific surface area is 10 m 2 / g or more, preferably 11 to 15 m
2 / g, the average particle diameter is 0.6 μm or less, preferably 0.4 to 0.6 μm
m, the internal oxygen content is less than 0.5% by weight, preferably 0.2%
% By weight and less than 0.5% by weight, and more preferably those having an external oxygen content of 0.5% by weight or less.
上記内部酸素含有量が0.5重量％を超えると、得られ
る焼結体の強度が低下し、本発明の目的を達成すること
ができない。また、α分率が90％未満である場合も強度
の点で問題を生じ、BET比表面積が10m2/g未満であると
焼結性に劣るものになってしまい、更に平均粒子径につ
いても、これが大きすぎると場合は焼結性に劣るものに
なる。When the internal oxygen content exceeds 0.5% by weight, the strength of the obtained sintered body is reduced, and the object of the present invention cannot be achieved. Also, when the α fraction is less than 90%, a problem occurs in terms of strength, and when the BET specific surface area is less than 10 m 2 / g, the sinterability becomes inferior. If this is too large, the sinterability will be poor.
ここで、上記内部酸素含有量及び外部酸素含有量の測
定は、LECO社製TC−436等の酸素分析装置を用い、昇温
形態分析により行うことができる。即ち、昇温形態分析
では、昇温の過程で多数のピークが出現するが、これら
のピークを下記判定法によりテイル型（尾を引くピー
ク）と対称型（線対称のピーク）とに大別し、下記式に
より内部酸素含有量及び外部酸素含有量を求めるもので
ある。Here, the measurement of the internal oxygen content and the external oxygen content can be performed by a temperature rising morphological analysis using an oxygen analyzer such as TC-436 manufactured by LECO. That is, in the temperature rise morphological analysis, a number of peaks appear during the process of temperature rise, and these peaks are roughly classified into a tail type (peak with a tail) and a symmetric type (peak with line symmetry) according to the following judgment method. Then, the internal oxygen content and the external oxygen content are determined by the following equations.
Wout＝Ｗ′−Win Win:内部酸素含有量 Wout:外部酸素含有量 Ｗ′：全酸素量（内部酸素量＋外部酸素量） SS：対称型ピークの積分値 ST：テイル型ピークの積分値 ここで、全酸素量は非分散赤外線吸収法により測定す
る。 Wout = W'-Win Win: Internal oxygen content Wout: External oxygen content W ': Total oxygen content (Internal oxygen content + External oxygen content) S S : Integral value of symmetrical peak S T : Integral of tail type peak Here, the total oxygen content is measured by a non-dispersive infrared absorption method.
ピークの判定法 対称型（SS）：第１図にしたしたピーク１の頂点２から
ｘ軸に下した線３の中間部４と、該中間部４においてｘ
軸と平行な線を引いたときに上記ピーク１と交わる点5,
6との距離a,bをそれぞれ測定した場合、即ちピーク１の
半値幅ｃ（ｃ＝ａ＋ｂ）において、a/bが0.8≦a/b≦1.1
であるピーク テイル型（ST）：ピーク１の半値幅ｃにおいて1.1＜a/b
であるピーク なお、第２図に示す昇温形態分析チャートにおいて、
対称型及びテイル型ピークは図示した通りである。Peak determination method Symmetric type (S S ): The middle part 4 of the line 3 drawn from the vertex 2 of the peak 1 shown in FIG.
Point 5, which intersects the above peak 1 when a line parallel to the axis is drawn,
When the distances a and b with respect to 6 were measured, that is, in the half width c of the peak 1 (c = a + b), a / b was 0.8 ≦ a / b ≦ 1.1.
Peak tail type (S T ): 1.1 <a / b at half width c of peak 1
In the temperature rise morphological analysis chart shown in FIG.
Symmetric and tail peaks are as shown.
なおまた、上記昇温形態分析は、０℃〜2000℃の範囲
で０〜300秒間程度行なうことが好ましい。In addition, it is preferable that the above-mentioned temperature rising morphological analysis is performed in the range of 0 ° C. to 2000 ° C. for about 0 to 300 seconds.
上記窒化ケイ素粉末は、金属ケイ素粉末を窒素ガス雰
囲気又は窒素を含む非酸化性ガス雰囲気下で加熱する通
常の直接窒化法において、原料の金属ケイ素粉末の酸素
含有量及び上記雰囲気中の水分量をコントロールするこ
とにより、製造することができる。この場合、金属ケイ
素粉末の粒度は１〜10μｍが好ましい。また、窒素を含
む非酸化性ガス雰囲気としては、水素ガスを５〜25容量
％程度含む窒素ガスとの水素ガス混合ガスからなる雰囲
気が好ましく用いられる。更に、窒化温度は通常1200〜
1400℃であり、窒化時間は通常２〜５時間程度である。The silicon nitride powder, in a normal direct nitridation method of heating the metal silicon powder under a nitrogen gas atmosphere or a non-oxidizing gas atmosphere containing nitrogen, the oxygen content of the raw metal silicon powder and the water content in the atmosphere It can be manufactured by controlling. In this case, the particle size of the metal silicon powder is preferably 1 to 10 μm. As the non-oxidizing gas atmosphere containing nitrogen, an atmosphere composed of a mixed gas of hydrogen gas and nitrogen gas containing about 5 to 25% by volume of hydrogen gas is preferably used. Furthermore, the nitriding temperature is usually 1200-
The temperature is 1400 ° C. and the nitriding time is usually about 2 to 5 hours.
而して、本発明の窒化ケイ素粉末は、上記製造法にお
いて、上記原料の金属ケイ素粉末として酸素含有量が１
重量％以下のものを用いると共に、上記雰囲気中の水分
量を該金属ケイ素粉末の酸素含有量に応じてコントロー
ルすることにより製造することができる。即ち、該原料
金属粉末の酸素含有量が0.4〜１重量％である場合は、
水分量を1000ppm未満に、好ましくは500ppm未満にコン
トロールし、一方、酸素含有量が0.4重量％未満の場合
は、水分量を1000〜6000ppm、好ましくは4000〜5000ppm
にコントロールすることにより、窒化ケイ素粉末の内部
酸素含有量を0.5重量％未満に制御することができるも
のである。Thus, the silicon nitride powder of the present invention may have an oxygen content of 1 as the raw material metal silicon powder in the above production method.
It can be produced by controlling the amount of water in the above atmosphere in accordance with the oxygen content of the metal silicon powder while using not more than 1% by weight. That is, when the oxygen content of the raw metal powder is 0.4 to 1% by weight,
The water content is controlled to less than 1000 ppm, preferably less than 500 ppm, while when the oxygen content is less than 0.4% by weight, the water content is 1000-6000 ppm, preferably 4000-5000 ppm.
, The internal oxygen content of the silicon nitride powder can be controlled to less than 0.5% by weight.
この場合、雰囲気中の水分量を上記範囲内において増
減することにより、得られる窒化ケイ素粉末の内部酸素
含有量を調節することができる。In this case, the internal oxygen content of the obtained silicon nitride powder can be adjusted by increasing or decreasing the amount of water in the atmosphere within the above range.
発明の効果 本発明の窒化ケイ素粉末は、これを焼結することによ
り強度に優れた窒化ケイ素焼結体を得ることができる。Effect of the Invention By sintering the silicon nitride powder of the present invention, a silicon nitride sintered body having excellent strength can be obtained.
以下、実施例及び比較例を示し、本発明を具体的に説
明するが、本発明は下記実施例に制限されるものではな
い。Hereinafter, the present invention will be described specifically with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples.
〔実施例１〜5,比較例１〜３〕 0.1〜0.4重量％の範囲の酸素含有量を有する金属ケイ
素粉末をN2とH2との混合ガスを水中に通し、水分を4300
ppm含有させたガス雰囲気下に最高温度1380℃でそれぞ
れ常法に従って加熱窒化し、これをそれぞれ湿式粉砕
し、HFとHNO3との混酸により酸処理して窒化ケイ素粉末
を得た。[Examples 1 to 5, Comparative Examples 1 to 3] A metal silicon powder having an oxygen content in the range of 0.1 to 0.4% by weight was passed through a mixed gas of N 2 and H 2 into water to remove water from 4300.
Each was heated and nitrided at a maximum temperature of 1380 ° C. in a gas atmosphere containing ppm according to a conventional method, and each was wet-pulverized and acid-treated with a mixed acid of HF and HNO 3 to obtain a silicon nitride powder.
これらの窒化ケイ素粉末のα分率、平均粒子径、BET
比表面積、内部酸素量、外部酸素量を測定した。その結
果を第１表に示す。Α fraction of these silicon nitride powders, average particle size, BET
The specific surface area, the amount of internal oxygen, and the amount of external oxygen were measured. Table 1 shows the results.
ここで、第１表中の窒化ケイ素粉末の内部酸素量は上
述した昇温形態分析法により測定し、外部酸素量は堀場
EMGA2800により測定した全酸素量から上記内部酸素量を
引いた値である。Here, the internal oxygen content of the silicon nitride powder in Table 1 was measured by the above-mentioned temperature rising form analysis method, and the external oxygen content was measured by Horiba
This is a value obtained by subtracting the internal oxygen content from the total oxygen content measured by EMGA2800.
なお、実施例１の窒化ケイ素粉末について行なった昇
温形態分析のチャートを第２図に示す。FIG. 2 shows a chart of the temperature rise morphological analysis performed on the silicon nitride powder of Example 1.
次に、上記窒化ケイ素粉末90部（重量部、以下同様）
にそれぞれY2O3７部、Al2O3３部を加え、ボールミルで
湿式混合し、乾燥後、2t/cm2の圧力で金型形成し、1800
℃で１時間焼結して棒状焼結体（３×4mm）を得た。こ
の焼結体の室温下での三点曲げ強度をJIS R−1601に基
づいて測定した。結果を第１表に併記する。Next, 90 parts of the above silicon nitride powder (parts by weight, the same applies hereinafter)
, 7 parts of Y 2 O 3 and 3 parts of Al 2 O 3 were added thereto, and wet-mixed with a ball mill. After drying, a mold was formed under a pressure of 2 t / cm 2 , and
C. for 1 hour to obtain a rod-shaped sintered body (3.times.4 mm). The three-point bending strength of this sintered body at room temperature was measured based on JIS R-1601. The results are shown in Table 1.
第１表の結果より、本発明の窒化ケイ素粉末から得た
焼結体は強度の向上したものであることが確認された。 From the results in Table 1, it was confirmed that the sintered body obtained from the silicon nitride powder of the present invention had improved strength.
〔実施例６〜8,比較例4,5〕 第２表に示したα分率、平均粒子径、比表面積、内部
酸素量及び外部酸素量を有する窒化ケイ素粉末を用い、
焼結時間を４時間とした以外は実施例１と同様の条件で
棒状焼結体（径3mm×長さ4mm）を得、1200℃の温度下で
三点曲げ強度をJIS R−1601に基づいて測定した。結果
を第２表に併記する。[Examples 6 to 8, Comparative Examples 4 and 5] Using a silicon nitride powder having the α fraction, average particle diameter, specific surface area, internal oxygen content and external oxygen content shown in Table 2,
A bar-shaped sintered body (diameter 3 mm x length 4 mm) was obtained under the same conditions as in Example 1 except that the sintering time was changed to 4 hours, and the three-point bending strength was determined at 1200 ° C based on JIS R-1601. Measured. The results are shown in Table 2.
第２表の結果より、本発明の窒化ケイ素粉末から得ら
れた焼結体は1200℃という高温下においてても高い強度
を有することが確認された。 From the results in Table 2, it was confirmed that the sintered body obtained from the silicon nitride powder of the present invention had high strength even at a high temperature of 1200 ° C.
第１図は、昇温形態分析におけるピークの判定法を説明
するためのグラフ、第２図は昇温形態分析により得られ
たチャートを示すグラフである。FIG. 1 is a graph for explaining a method of determining a peak in the temperature rise mode analysis, and FIG. 2 is a graph showing a chart obtained by the temperature rise mode analysis.
Claims (3)
末を窒素ガス雰囲気又は窒素を含む非酸化性ガス雰囲気
でこの雰囲気中の水分量をコントロールすることにより
製造され、α分率が90％以上、BET比表面積が10m2/g以
上、平均粒子径が0.6μｍ以下で、内部酸素含有量が0.5
重量％未満であることを特徴とする窒化ケイ素粉末。1. A metal silicon powder having an oxygen content of 1% by weight or less is produced in a nitrogen gas atmosphere or a non-oxidizing gas atmosphere containing nitrogen by controlling the water content in the atmosphere. % Or more, the BET specific surface area is 10 m 2 / g or more, the average particle diameter is 0.6 μm or less, and the internal oxygen content is 0.5
A silicon nitride powder, which is less than 10% by weight.
求項１記載の窒化ケイ素粉末。2. The silicon nitride powder according to claim 1, wherein the external oxygen content is 0.5% by weight or less.
量が0.4〜１重量％の場合1000ppm未満であり、金属ケイ
素粉末の酸素含有量が0.4重量％未満の場合1000〜6000p
pmである請求項１又は２記載の窒化ケイ素粉末。3. The water content is less than 1000 ppm when the oxygen content of the metal silicon powder is 0.4 to 1% by weight, and 1000 to 6000 ppm when the oxygen content of the metal silicon powder is less than 0.4% by weight.
3. The silicon nitride powder according to claim 1, which is pm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23424190A JP2874057B2 (en) | 1990-09-03 | 1990-09-03 | Silicon nitride powder |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23424190A JP2874057B2 (en) | 1990-09-03 | 1990-09-03 | Silicon nitride powder |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04114908A JPH04114908A (en) | 1992-04-15 |
| JP2874057B2 true JP2874057B2 (en) | 1999-03-24 |
Family
ID=16967895
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP23424190A Expired - Fee Related JP2874057B2 (en) | 1990-09-03 | 1990-09-03 | Silicon nitride powder |
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| Country | Link |
|---|---|
| JP (1) | JP2874057B2 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101652616B1 (en) | 2012-03-28 | 2016-08-30 | 우베 고산 가부시키가이샤 | Silicon nitride powder production method, silicon nitride powder, silicon nitride sintered body and circuit substrate using same |
| JP6077193B1 (en) * | 2015-04-20 | 2017-02-08 | 株式会社Tkx | Method for producing silicon fine powder and method for producing silicon nitride fine powder |
| WO2020203695A1 (en) * | 2019-03-29 | 2020-10-08 | デンカ株式会社 | Silicon nitride powder and production method therefor, and production method for silicon nitride sintered body |
| KR102408533B1 (en) * | 2021-11-25 | 2022-06-14 | 주식회사 첨단랩 | Manufacturing method of silicon nitride filler for thermal interface material |
-
1990
- 1990-09-03 JP JP23424190A patent/JP2874057B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH04114908A (en) | 1992-04-15 |
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