JPH0331667B2 - - Google Patents
Info
- Publication number
- JPH0331667B2 JPH0331667B2 JP61311652A JP31165286A JPH0331667B2 JP H0331667 B2 JPH0331667 B2 JP H0331667B2 JP 61311652 A JP61311652 A JP 61311652A JP 31165286 A JP31165286 A JP 31165286A JP H0331667 B2 JPH0331667 B2 JP H0331667B2
- Authority
- JP
- Japan
- Prior art keywords
- sintered body
- surface layer
- boron
- mixed gas
- carbon
- 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.)
- Expired - Lifetime
Links
- 239000002344 surface layer Substances 0.000 claims description 24
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 claims description 14
- 229910052796 boron Inorganic materials 0.000 claims description 14
- 150000001639 boron compounds Chemical class 0.000 claims description 12
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 9
- 238000000034 method Methods 0.000 claims description 9
- 229910052799 carbon Inorganic materials 0.000 claims description 8
- 150000001722 carbon compounds Chemical class 0.000 claims description 8
- 239000011247 coating layer Substances 0.000 claims description 8
- 239000011148 porous material Substances 0.000 claims description 6
- 238000002156 mixing Methods 0.000 claims description 4
- 239000000203 mixture Substances 0.000 claims description 4
- 238000013459 approach Methods 0.000 claims description 2
- 239000007789 gas Substances 0.000 description 18
- 230000000694 effects Effects 0.000 description 7
- 238000004519 manufacturing process Methods 0.000 description 7
- 239000000463 material Substances 0.000 description 5
- 239000000843 powder Substances 0.000 description 5
- 238000001272 pressureless sintering Methods 0.000 description 4
- 238000005245 sintering Methods 0.000 description 4
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 3
- 230000004927 fusion Effects 0.000 description 3
- 229910016569 AlF 3 Inorganic materials 0.000 description 2
- 229910003481 amorphous carbon Inorganic materials 0.000 description 2
- 150000001721 carbon Chemical class 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 238000003825 pressing Methods 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 239000007858 starting material Substances 0.000 description 2
- VZGDMQKNWNREIO-UHFFFAOYSA-N tetrachloromethane Chemical compound ClC(Cl)(Cl)Cl VZGDMQKNWNREIO-UHFFFAOYSA-N 0.000 description 2
- 229910015844 BCl3 Inorganic materials 0.000 description 1
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 239000012300 argon atmosphere Substances 0.000 description 1
- UORVGPXVDQYIDP-UHFFFAOYSA-N borane Chemical compound B UORVGPXVDQYIDP-UHFFFAOYSA-N 0.000 description 1
- 150000001638 boron Chemical class 0.000 description 1
- 229910010277 boron hydride Inorganic materials 0.000 description 1
- 239000003610 charcoal Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 238000002407 reforming Methods 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
- FAQYAMRNWDIXMY-UHFFFAOYSA-N trichloroborane Chemical compound ClB(Cl)Cl FAQYAMRNWDIXMY-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Ceramic Products (AREA)
- Powder Metallurgy (AREA)
Description
【発明の詳細な説明】
（産業上の利用分野）
本願発明は、例えば核融合炉用の中性子遮蔽材
としての利用の可能性があるB4C焼結体の表面層
改質法に関する。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for modifying the surface layer of a B 4 C sintered body, which may be used as a neutron shielding material for, for example, a nuclear fusion reactor.
（従来の技術）
最近B4C焼結体には、核融合炉の中性子遮蔽材
としての利用が可能であることが明らかになり、
その物性等が注目されている。(Prior art) It has recently become clear that B 4 C sintered bodies can be used as neutron shielding materials in nuclear fusion reactors.
Its physical properties are attracting attention.
従来、B4C焼結体の製造法はB4C粉末をホツト
プレスを利用して高温高圧で固める手法が主であ
るが、またB4C粉末中に５〜10％の金属添加物を
加え、常圧焼結によつて製造する方法も知られて
いる。 Conventionally, the main method for manufacturing B 4 C sintered bodies is to solidify B 4 C powder at high temperature and pressure using a hot press, but it is also possible to add 5 to 10% metal additives to B 4 C powder. A method of manufacturing by pressureless sintering is also known.
（発明が解決しようとする問題点）
しかし、常圧焼結によるB4C焼結体の製造にお
いては複雑な形状のものが製造することができる
という利点がある反面、理論密度90％以上の焼結
体の製造が困難であるという欠点がある。(Problem to be solved by the invention) However, in the production of B 4 C sintered bodies by pressureless sintering, although it has the advantage of being able to produce products with complex shapes, The disadvantage is that the sintered body is difficult to manufacture.
一方、ホツトプレスを利用した高温高圧による
B4C焼結体の製造においては複雑な形状のものを
製造することが困難である反面、理論密度90％以
上のものが製造可能となる。 On the other hand, the high temperature and high pressure using a hot press
Although it is difficult to manufacture B 4 C sintered bodies with complex shapes, it is possible to manufacture bodies with a theoretical density of 90% or more.
しかし、この方法により製造されたB4C焼結体
についても中性子遮蔽効果が不十分であり、また
焼結法により製造されたB4C焼結体には強度面で
信頼性に欠けるなどの難点がある。 However, the neutron shielding effect of the B 4 C sintered body manufactured by this method is insufficient, and the B 4 C sintered body manufactured by the sintering method lacks reliability in terms of strength. There are some difficulties.
本願発明は、上記実情に鑑み十分な中性子遮蔽
効果と強度を有するB4C焼結体を得ることを目的
とするものである。 In view of the above circumstances, the present invention aims to obtain a B 4 C sintered body having sufficient neutron shielding effect and strength.
（問題点を解決するための手段）
以上の問題点を解決するため、本願発明では
B4C焼結体の混合ガス改質法を提案するものであ
る。(Means for solving the problems) In order to solve the above problems, the claimed invention
This paper proposes a mixed gas reforming method for B 4 C sintered bodies.
本願第１発明においては、B4C焼結体に、1400
〜1500℃でボロン化合物、炭素化合物、キヤリヤ
からなる混合ガスを接触させ、B4C焼結体表面層
近傍の気孔中に上記混合ガス含浸させるととも
に、該気孔中で混合ガス中のボロン乃至炭素を結
晶化させてB4C焼結体表面層を強化するものであ
る。 In the first invention of the present application, 1400
A mixed gas consisting of a boron compound, a carbon compound, and a carrier is brought into contact at ~1500°C, and the mixed gas is impregnated into the pores near the surface layer of the B 4 C sintered body. This strengthens the surface layer of the B 4 C sintered body by crystallizing it.
本願第２、第３発明においては、B4C焼結体
に、1700〜1900℃でボロン化合物、炭素化合物、
キヤリヤからなる混合ガスを接触させ、B4C焼結
体表面層で該混合ガス中のボロン乃至炭素を結晶
化させてB4C焼結体表面層面にBxCy被覆層を形
成するものである。 In the second and third inventions of the present application, a boron compound, a carbon compound,
A method in which a mixed gas consisting of a carrier is brought into contact with the surface layer of the B 4 C sintered body to crystallize boron or carbon in the mixed gas, thereby forming a B x C y coating layer on the surface layer of the B 4 C sintered body. It is.
本願第１〜第３発明においてB4C焼結体として
は従来の常圧焼結、高温高圧焼結により得られた
ものを使用することができる。 In the first to third inventions of the present application, as the B 4 C sintered body, those obtained by conventional normal pressure sintering or high temperature and high pressure sintering can be used.
また、本願発明者の研究によればAlF3、非晶
質カーボン、非晶質ボロンを焼結助剤としてB4C
粉末中に微量添加することによつて常圧焼結で理
論密度94％のものを得ることができるので、これ
を使用してもよい。なお、この場合は高密度であ
り、しかも常圧焼結であるため、複雑な形状の焼
結体の製造が容易になり、したがつてこの方法に
より得られたB4C焼結体を原料とすれば、任意形
状の中性子遮蔽材を得ることができる。 In addition, according to research by the inventor of the present application, B 4 C using AlF 3 , amorphous carbon, and amorphous boron as sintering aids
By adding a small amount to the powder, a product with a theoretical density of 94% can be obtained by pressureless sintering, so this may be used. In this case, since the density is high and pressureless sintering is used, it is easy to manufacture a sintered body with a complicated shape. If so, a neutron shielding material having an arbitrary shape can be obtained.
本願第１〜第３発明において混合ガスを構成す
るボロン化合物としてはBCl3等のハロゲン化ボ
ロン、水素化ボロン等を使用することができ、ま
た炭素化合物としては四塩化炭素等のハロゲン化
炭素、C3H8等の水素化炭素等を使用することが
でき、更にキヤリヤとしては水素ガス等を使用す
ることができる。 In the first to third inventions of the present application, halogenated boron such as BCl3 , boron hydride, etc. can be used as the boron compound constituting the mixed gas, and as the carbon compound, halogenated carbon such as carbon tetrachloride, Hydrogenated carbon such as C 3 H 8 or the like can be used, and hydrogen gas or the like can be used as a carrier.
一方、本願第１発明において1400℃〜1500℃に
保たれたB4C焼結体に、上記混合ガスを接触させ
る。 On the other hand, in the first invention of the present application, the mixed gas is brought into contact with the B 4 C sintered body kept at 1400°C to 1500°C.
また、本願第２、第３発明において1700℃〜
1900℃に保たれたB4C焼結体に、上記混合ガスを
接触させる。 In addition, in the second and third inventions of the present application, 1700℃~
The above mixed gas is brought into contact with the B 4 C sintered body maintained at 1900°C.
なお、本願第３発明ではB4C焼結体に接触させ
る上記混合ガス中のボロン化合物の混合割合を順
次高めるようにする。 In addition, in the third invention of the present application, the mixing ratio of the boron compound in the above-mentioned mixed gas brought into contact with the B 4 C sintered body is gradually increased.
上記した本願第１〜第３発明における接触温度
の範囲外では、ボロン乃至炭素の結晶化が良好で
はなかつた。 Crystallization of boron to carbon was not good outside the contact temperature range in the first to third inventions of the present application described above.
（発明の効果）
以上、本願第１発明によればB4C焼結体に、
1400〜1500℃の比較的低温下でボロン化合物、炭
素化合物、キヤリヤからなる混合ガスを接触させ
るので、混合ガスはB4C焼結体表面層近傍の気孔
中に含浸され、ここでボロン乃至炭素を析出して
結晶化させる。(Effect of the invention) As described above, according to the first invention of the present application, in the B 4 C sintered body,
Since a mixed gas consisting of a boron compound, a carbon compound, and a carrier is brought into contact at a relatively low temperature of 1400 to 1500°C, the mixed gas is impregnated into the pores near the surface layer of the B 4 C sintered body, where boron to carbon is precipitated and crystallized.
したがつて、本願第１発明によればB4C焼結体
の表面層の近傍に存在する気孔はBxCyの結晶に
よつて充填される。このため、中性子等の遮蔽効
果が高められると同時に、表面層の強度が強化さ
れる。 Therefore, according to the first invention of the present application, the pores existing near the surface layer of the B 4 C sintered body are filled with B x C y crystals. Therefore, the shielding effect against neutrons and the like is enhanced, and at the same time, the strength of the surface layer is strengthened.
また、本願第２発明においてはB4C焼結体に、
ボロン化合物、炭素化合物、キヤリヤからなる混
合ガスを接触させるが、第１発明に比べて1700〜
1900℃の比較的高温で接触させるため、B4C焼結
体表面層で混合ガス中のボロン乃至炭素が析出し
て結晶化され、B4C焼結体表面層面にBxCy被覆
層を形成する。 In addition, in the second invention of the present application, in the B 4 C sintered body,
A mixed gas consisting of a boron compound, a carbon compound, and a carrier is brought into contact with each other.
Because the contact is carried out at a relatively high temperature of 1900℃, boron or carbon in the mixed gas is precipitated and crystallized on the surface layer of the B 4 C sintered body, and a B x C y coating layer is formed on the surface layer of the B 4 C sintered body. form.
したがつて、本願第２発明においても中性子等
の遮蔽効果が高められると同時に、表面層の強度
が強化される。 Therefore, in the second invention of the present application as well, the shielding effect against neutrons and the like is enhanced, and at the same time, the strength of the surface layer is strengthened.
更に、本願第３発明においては上記第２発明に
おいてB4C焼結体に接触させる上記混合ガス中の
ボロン化合物の混合割合を順次高めるようにする
ものであるが、本願第３発明によればB4C焼結体
の表面層に形成されたBxCy被覆層は表面に近ず
くに従つてボロンの割合が高いため、中性子の遮
蔽がより効果的に行なわれる。 Furthermore, in the third invention of the present application, in the second invention, the mixing ratio of the boron compound in the mixed gas that is brought into contact with the B 4 C sintered body is gradually increased, but according to the third invention of the present application, Since the B x C y coating layer formed on the surface layer of the B 4 C sintered body has a higher proportion of boron as it approaches the surface, neutron shielding is performed more effectively.
なお、この場合B4C焼結体の表面層とBxCy被
覆層とが剥離したり、BxCy被覆層の内部におけ
る熱膨張係数の値が不連続にならないように混合
ガス中ボロン化合物の配合割合を極微量づつ増加
させるようにする。 In this case, in order to prevent the surface layer of the B 4 C sintered body from peeling off from the B x C y coating layer and to prevent discontinuity in the value of the thermal expansion coefficient inside the B x C y coating layer, The blending ratio of the boron compound is increased little by little.
以上要するに、本願第１〜第３発明によれば中
性子の遮蔽効果が向上すると同時に、B4C焼結体
の表面層の強度が強化され、核融合炉等の高温下
においてもB4C焼結体の高温強度が損なわれるこ
とがない。したがつて、本願発明によつて処理さ
れたB4C焼結体は高温強度材料としての利用の他
に、核融合炉用高性能中性子遮蔽材としての利用
が見込まれ、エネルギー確保のための有力な手段
となる。 In summary, according to the first to third inventions of the present application, the neutron shielding effect is improved, and at the same time, the strength of the surface layer of the B 4 C sintered body is strengthened, and the B 4 C sintered body is The high temperature strength of the compact is not impaired. Therefore, in addition to being used as a high-temperature strength material, the B 4 C sintered body processed according to the present invention is expected to be used as a high-performance neutron shielding material for nuclear fusion reactors, and is useful for securing energy. It is a powerful tool.
（実施例） 以下、この発明の実施例を示す。(Example) Examples of this invention will be shown below.
実施例 １
AlF3、非晶質カーボン、非晶質ボロンを全体
でB4C粉末の４〜５％をメタノール中に懸濁さ
せ、B4C粉末をこの懸濁液中に入れ、一晩混合す
る。その後、真空乾燥し、粉砕ふるい分けをして
出発原料とする。Example 1 AlF 3 , amorphous carbon, amorphous boron with a total of 4-5% of B 4 C powder is suspended in methanol, B 4 C powder is placed in this suspension and left overnight. Mix. Thereafter, it is vacuum dried, crushed and sieved to be used as a starting material.
この出発原料を金型プレス、ラバープレス処理
し、B4C成形体を得た。この成形体を真空炉を用
いてアルゴン雰囲気下で2200℃にて30分間焼成
し、理論密度94％の焼結体を得る。 This starting material was subjected to mold pressing and rubber pressing to obtain a B 4 C molded body. This molded body is fired for 30 minutes at 2200°C in an argon atmosphere using a vacuum furnace to obtain a sintered body with a theoretical density of 94%.
次に、上記のようにして得られたB4C焼結体を
1400〜1500℃に保ち、これにノズルより
BCl3 +CCl4 +H2混合ガスを吹き付けた。 Next, the B 4 C sintered body obtained as described above was
Maintain the temperature at 1400~1500℃, and then use the nozzle to
BCl 3 + CCl 4 + H 2 mixed gas was sprayed.
これにより、B4C焼結体の表面層近傍にある気
孔はBxCyの結晶で充填され、B4C焼結体の表面
強化を図ることができた。 As a result, the pores near the surface layer of the B 4 C sintered body were filled with B x C y crystals, making it possible to strengthen the surface of the B 4 C sintered body.
実施例 ２
上記実施例１で得られたB4C焼結体を1700℃〜
1900℃に保ち、これにノズルよりBCl3 +CCl4 +H2
混合ガスを吹き付け、その後混合ガス中のCCl4
の配合量を徐々に減少させ、他の成分の配合量を
一定にしてノズルより吹き付けた。Example 2 The B 4 C sintered body obtained in Example 1 above was heated to 1700°C
Keep at 1900℃ and add BCl 3 + CCl 4 + H 2 from the nozzle to this.
Spray the mixed gas, then CCl 4 in the mixed gas
was sprayed from a nozzle while gradually decreasing the amount of other components and keeping the amounts of other components constant.
この結果、B4C焼結体の表面層上にはボロンと
炭素が析出して結晶化し、BxCyの被覆層を形成
するが、この実施例では混合ガス中のCCl4の配
合量を徐々に減少させ、他の成分の配合量を一定
にしてノズルより吹き付けているため、B4C焼結
体の表面層上に析出されるボロンと炭素の量は
B4C組成より微量づつボロンの割合が増加し、最
終的にはB4C組成の化合物の形態で析出を終え
た。 As a result, boron and carbon precipitate and crystallize on the surface layer of the B 4 C sintered body, forming a coating layer of B x C y . In this example, the amount of CCl 4 in the mixed gas The amount of boron and carbon deposited on the surface layer of the B 4 C sintered body is
The proportion of boron increased little by little compared to the B 4 C composition, and finally the precipitation was completed in the form of a compound with the B 4 C composition.
このように処理したB4C焼結体は表面がボロン
に富むため、中性子遮蔽効果が優れたものであつ
た。 Since the surface of the B 4 C sintered body treated in this manner was rich in boron, it had an excellent neutron shielding effect.
Claims (1)
物、炭素化合物、キヤリヤからなる混合ガスを接
触させ、B4C焼結体表面層近傍の気孔中に上記混
合ガスを含浸させるとともに、該気孔中で混合ガ
ス中のボロン乃至炭素を結晶化させてB4C焼結体
表面層を強化することを特徴とするB4C焼結体の
表面層改質法。 ２ B4C焼結体に、1700〜1900℃でボロン化合
物、炭素化合物、キヤリヤからなる混合ガスを接
触させ、B4C焼結体表面層で該混合ガス中のボロ
ン乃至炭素を結晶化させてB4C焼結体表面層面に
BxCy被覆層を形成することを特徴とするB4C焼
結体の表面層改質法。 ３ B4C焼結体に接触させる上記ボロン化合物、
炭素化合物、キヤリヤからなる混合ガス中のボロ
ン化合物の混合割合を順次高めることにより表面
に近づくに従つてボロンの割合が高いBxCy被覆
層を形成するようにしたことを特徴とする特許請
求の範囲２項に記載のB4C焼結体の表面層改質
法。[Claims] 1 A mixed gas consisting of a boron compound, a carbon compound, and a carrier is brought into contact with a B 4 C sintered body at 1400 to 1500°C, and the above mixture is produced in the pores near the surface layer of the B 4 C sintered body. A method for modifying the surface layer of a B 4 C sintered body, characterized by impregnating the body with gas and crystallizing boron or carbon in the mixed gas in the pores to strengthen the surface layer of the B 4 C sintered body. . 2 A mixed gas consisting of a boron compound, a carbon compound, and a carrier is brought into contact with the B 4 C sintered body at 1700 to 1900°C, and the boron to carbon in the mixed gas is crystallized on the surface layer of the B 4 C sintered body. B 4 C on the surface layer of the sintered body
A method for modifying the surface layer of a B 4 C sintered body, characterized by forming a B x C y coating layer. 3 The above boron compound brought into contact with the B 4 C sintered body,
A patent claim characterized in that a B x C y coating layer in which the proportion of boron increases as it approaches the surface is formed by sequentially increasing the mixing proportion of a boron compound in a mixed gas consisting of a carbon compound and a carrier. A method for modifying the surface layer of a B 4 C sintered body according to item 2.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61311652A JPH01172266A (en) | 1986-12-26 | 1986-12-26 | Process for modifying surface layer of sintered b4c |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP61311652A JPH01172266A (en) | 1986-12-26 | 1986-12-26 | Process for modifying surface layer of sintered b4c |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01172266A JPH01172266A (en) | 1989-07-07 |
| JPH0331667B2 true JPH0331667B2 (en) | 1991-05-08 |
Family
ID=18019858
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP61311652A Granted JPH01172266A (en) | 1986-12-26 | 1986-12-26 | Process for modifying surface layer of sintered b4c |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01172266A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5785003B2 (en) * | 2011-06-29 | 2015-09-24 | 日本ファインセラミックス株式会社 | Manufacturing method of composite material |
| CN109940163B (en) * | 2019-05-15 | 2020-12-11 | 四川大学 | Post-processing method for enhancing surface wear resistance of 3D printed metal part |
-
1986
- 1986-12-26 JP JP61311652A patent/JPH01172266A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01172266A (en) | 1989-07-07 |
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