JPS63111101A - Spheroidizing method for metal or alloy powder - Google Patents
Spheroidizing method for metal or alloy powderInfo
- Publication number
- JPS63111101A JPS63111101A JP61256922A JP25692286A JPS63111101A JP S63111101 A JPS63111101 A JP S63111101A JP 61256922 A JP61256922 A JP 61256922A JP 25692286 A JP25692286 A JP 25692286A JP S63111101 A JPS63111101 A JP S63111101A
- Authority
- JP
- Japan
- Prior art keywords
- powder
- metal
- alloy
- chamber
- gas
- 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.)
- Pending
Links
- 239000000843 powder Substances 0.000 title claims abstract description 66
- 229910045601 alloy Inorganic materials 0.000 title claims abstract description 27
- 239000000956 alloy Substances 0.000 title claims abstract description 27
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 27
- 239000002184 metal Substances 0.000 title claims abstract description 27
- 238000000034 method Methods 0.000 title claims abstract description 20
- 230000000630 rising effect Effects 0.000 claims 1
- 238000010438 heat treatment Methods 0.000 abstract description 27
- 238000009689 gas atomisation Methods 0.000 abstract description 8
- 230000001681 protective effect Effects 0.000 abstract description 6
- 238000002844 melting Methods 0.000 abstract description 4
- 230000008018 melting Effects 0.000 abstract description 4
- 238000010298 pulverizing process Methods 0.000 abstract description 3
- 238000001816 cooling Methods 0.000 abstract description 2
- 239000000155 melt Substances 0.000 abstract description 2
- 230000001174 ascending effect Effects 0.000 abstract 1
- 239000007789 gas Substances 0.000 description 11
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 4
- 238000009688 liquid atomisation Methods 0.000 description 4
- 239000002245 particle Substances 0.000 description 4
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 150000002739 metals Chemical class 0.000 description 3
- 238000010926 purge Methods 0.000 description 3
- 229910000679 solder Inorganic materials 0.000 description 3
- 238000005507 spraying Methods 0.000 description 3
- 229910052786 argon Inorganic materials 0.000 description 2
- 229910001873 dinitrogen Inorganic materials 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 238000011084 recovery Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 239000004570 mortar (masonry) Substances 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 238000007639 printing Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
Landscapes
- Powder Metallurgy (AREA)
Abstract
Description
【発明の詳細な説明】 (産業上の利用分野) 本発明は金属もしくは合金粉末の球状化方法に関する。[Detailed description of the invention] (Industrial application field) The present invention relates to a method for spheroidizing metal or alloy powder.
(従来の技術)
金属もしくは合金粉末は近年、非常に広い分野で用いら
れているが、例えば、粉末をペースト化し、このペース
トを塗布あるいは印刷する工程を含む分野などにおいて
は、粉末の流動性が良好であることが望ましく、そのた
めには、球状の粉末を得ることが必要となる。(Prior Art) Metal or alloy powders have been used in a very wide range of fields in recent years, but for example, in fields that involve the process of turning powder into a paste and applying or printing this paste, the fluidity of the powder is insufficient. A good quality is desirable, and for this purpose it is necessary to obtain a spherical powder.
一般に、金属もしくは合金粉末を製造する方法としては
、機械的粉砕法、ガスもしくは液体による噴霧法などが
使用されている。Generally, methods for producing metal or alloy powder include mechanical pulverization, gas or liquid atomization, and the like.
(発明が解決しようとする問題点)
しかしながら、前述した粉末の製造方法のうち、機械的
粉砕法および液体噴霧法では金属もしくは合金の球状粉
末を得ることは一般に困難である。(Problems to be Solved by the Invention) However, among the powder manufacturing methods described above, it is generally difficult to obtain spherical metal or alloy powder using the mechanical crushing method and the liquid spraying method.
また、ガス噴霧法では、例えば、ステンレス鋼などの表
面張力が比較的大きな金属もしくは合金については容易
に球状粉末を得ることが可能であるが、例えば、はんだ
などの、表面張力が比較的小さい金属もしくは合金は、
噴霧時の乱気流の影響を受は易く、粒形状が球状となり
に<<、通常はアスペクト比(粒子の長径/粒子の短径
)が2〜3の細長い形状になってしまうという問題があ
る。In addition, with the gas atomization method, it is possible to easily obtain spherical powder for metals or alloys with relatively high surface tension, such as stainless steel, but for metals with relatively low surface tension, such as solder, for example. Or the alloy is
It is easily affected by turbulence during spraying, and there is a problem that the particle shape becomes spherical and usually becomes an elongated shape with an aspect ratio (longer diameter of the particle/breadth diameter of the particle) of 2 to 3.
本発明は上記問題点を解決するためになされたもので、
公知の粉末製造法、具体的には機械的粉砕法、液体噴霧
法およびガス噴霧法などにより得られた非球状の金属も
しくは合金粉末を球状化するために有効な金属もしくは
合金粉末の球状化方法を提供することを目的とする。The present invention has been made to solve the above problems,
A method for spheronizing metal or alloy powder that is effective for spheronizing non-spherical metal or alloy powder obtained by known powder manufacturing methods, specifically mechanical pulverization, liquid atomization, gas atomization, etc. The purpose is to provide
(問題点を解決するための手段および作用)本発明は、
公知の方法、すなわち、機械的粉砕法、液体噴霧法およ
びガス噴霧法などにより得られた、非球状の金属もしく
は合金母粉末を加熱溶融したのち、自然落下もしくはそ
れに近い速度で静かに落下させることによって冷却・凝
固を行わせれば、球状の粉末を得ることができるとの認
識にもとづいてなされたものである。すなわち上記目的
を達成するために、本発明によれば、金属もしくは合金
よりなる母粉末を、該金属もしくは合金を溶融させうる
温度に保持された高温域を通過させて一旦溶融させたの
ち落下させ、この落下途中で冷却・凝固させることとし
たものである。(Means and effects for solving the problems) The present invention has the following features:
After heating and melting a non-spherical metal or alloy mother powder obtained by a known method, such as a mechanical crushing method, a liquid atomization method, a gas atomization method, etc., it is allowed to fall gently at a natural fall rate or at a speed close to that. This was based on the recognition that a spherical powder could be obtained by cooling and solidifying the powder. That is, in order to achieve the above object, according to the present invention, a base powder made of a metal or an alloy is passed through a high temperature region maintained at a temperature that can melt the metal or alloy, once melted, and then dropped. , it was decided that it would be cooled and solidified during this fall.
本発明の球状化方法において、まず、出発物質である金
属もしくは合金としては、とくに限定されるものではな
く、通常の機械的粉砕法、液体噴霧法およびガス噴霧法
では球状化しにくい金属もしくは合金であればいかなる
ものであってもよい。In the spheroidization method of the present invention, first, the metal or alloy that is the starting material is not particularly limited, and is a metal or alloy that is difficult to be spheroidized by ordinary mechanical grinding, liquid spraying, or gas atomization. It can be anything.
以下、本発明の粉末の球状化工程を第1図に基づいて詳
述する。Hereinafter, the powder spheroidization process of the present invention will be explained in detail based on FIG. 1.
第1図は本発明の球状化方法を実施する際に使用する装
置の一例である縦型高温管状炉を示す。FIG. 1 shows a vertical high-temperature tubular furnace which is an example of an apparatus used in carrying out the spheroidization method of the present invention.
図において、縦型高温管状炉1は試料導入チャンバla
、加熱チャンバ1bおよびこの加熱チャンバ1bに連通
ずる粉末回収チャンバ1cから構成される。試料導入チ
ャンバ1aと加熱チャンバ1bとは試料加熱管2により
互いに連通しており、加熱管2の外周壁にはヒータ3が
配設されている。In the figure, a vertical high-temperature tubular furnace 1 has a sample introduction chamber la.
, a heating chamber 1b, and a powder recovery chamber 1c communicating with the heating chamber 1b. The sample introduction chamber 1a and the heating chamber 1b communicate with each other through a sample heating tube 2, and a heater 3 is disposed on the outer peripheral wall of the heating tube 2.
このヒータ3の種類は母粉末の融点、粒径などに応じて
適宜選択されることが好ましい。加熱管2の上部には試
料ホッパ4が配設され、加熱チャンバ1bの底面はすり
鉢状に形成されてその底面最下部は前記粉末回収チャン
バ1cに接続されている。試料ホッパ4から球状化され
るべき母粉末は加熱管2を通って加熱チャンバ1bの底
面に落下し、すり鉢状の底面を滑落して回収チャンバl
cに回収される。The type of heater 3 is preferably selected appropriately depending on the melting point, particle size, etc. of the base powder. A sample hopper 4 is disposed at the top of the heating tube 2, and the bottom of the heating chamber 1b is shaped like a mortar, and the lowest part of the bottom is connected to the powder recovery chamber 1c. The mother powder to be spheroidized from the sample hopper 4 passes through the heating tube 2 and falls to the bottom of the heating chamber 1b, and slides down the mortar-shaped bottom to the collection chamber l.
It is collected at c.
一方、試料4入チャンバ1aには原料母粉末を保護し、
また、必要に応じて該母粉末に所定の流速を付与するた
めの保護雰囲気ガス導入管5が連通しており、加熱チャ
ンバ1bの底部にはパージ管6、および通路7を介して
真空ポンプ8が夫々接続されている。なお、図中、符号
9は保護雰囲気ガス導入管に配設され、雰囲気ガスの流
量を調節するためのバルブを、また、符号IOおよび1
1は通路7およびパージ管6にそれぞれ配設されたバル
ブを表わす。On the other hand, the raw material base powder is protected in the sample 4 chamber 1a,
Further, a protective atmosphere gas introduction pipe 5 for imparting a predetermined flow rate to the mother powder is connected to the bottom of the heating chamber 1b as needed, and a vacuum pump 8 is connected to the bottom of the heating chamber 1b via a purge pipe 6 and a passage 7. are connected to each other. In the figure, reference numeral 9 indicates a valve installed in the protective atmosphere gas introduction pipe, and a valve for adjusting the flow rate of the atmosphere gas, and reference numerals IO and 1
1 represents valves disposed in the passage 7 and the purge pipe 6, respectively.
まず、試料である母粉末の導入後に、真空ポンプ8によ
り管状炉1内を真空排気したのち、パージ管6により、
炉内を例えば窒素ガス、アルゴンガスなどで置換する。First, after introducing the mother powder as a sample, the inside of the tube furnace 1 is evacuated by the vacuum pump 8, and then the purge pipe 6 is used to evacuate the tube furnace 1.
The inside of the furnace is replaced with, for example, nitrogen gas or argon gas.
この操作は必ずしも必要とされないが、母粉末が酸化さ
れやすい金属もしくは合金よりなる場合はとくに有効で
ある。次いで、試料導入チャンバla内に保護雰囲気ガ
ス導入管5から保護雰囲気ガスとして、例えば窒素ガス
、アルゴンガスなどを導入する。この状態で、まずヒー
タ3に通電して、加熱管2を母粉末を溶融しうる温度と
なるまで加熱し、しかるのち、試料ホッパ4から母粉末
を落下させる。母粉末は加熱管2内を通過する際に溶融
し、自然落下もしくはそれに近い状態であるため溶融し
た粉末は球状となる。球状化した粉末は加熱管2を通過
後に加熱チャンバlb内を落下する過程で冷却されて凝
固し、粉末回収チャンバ1c内に捕集される。このよう
に、加熱チャンバ1bは、加熱管2で溶融した母粉末が
粉末回収チャンバ1cに到達する前に冷却・凝固するよ
うにその高さを決定することが好ましい。Although this operation is not necessarily required, it is particularly effective when the base powder is made of a metal or alloy that is easily oxidized. Next, a protective atmosphere gas such as nitrogen gas or argon gas is introduced into the sample introduction chamber la from the protective atmosphere gas introduction pipe 5. In this state, first, the heater 3 is energized to heat the heating tube 2 to a temperature that can melt the base powder, and then the base powder is dropped from the sample hopper 4. The base powder melts when passing through the heating tube 2, and since it falls naturally or is in a state close to it, the melted powder becomes spherical. After passing through the heating tube 2, the spheroidized powder is cooled and solidified while falling in the heating chamber 1b, and is collected in the powder collection chamber 1c. In this way, the height of the heating chamber 1b is preferably determined so that the mother powder melted in the heating tube 2 is cooled and solidified before reaching the powder collection chamber 1c.
なお、この母粉末の球状化工程において、母粉末が非常
に微細なものであったり、あるいは比重が軽いものであ
ったりして、加熱管2内の高温域で生じる上昇気流を受
けて自然に落下することが困難である場合には、保護雰
囲気ガスの流量を2朽整して、前記上昇気流に打ち勝っ
て落下するように流速を母粉末に付与することが好まし
い。In addition, in this step of spheroidizing the base powder, if the base powder is very fine or has a light specific gravity, it will naturally spheroidize due to the upward airflow generated in the high temperature area inside the heating tube 2. If it is difficult for the mother powder to fall, it is preferable to adjust the flow rate of the protective atmosphere gas to give the mother powder a flow velocity so that it can overcome the upward airflow and fall.
(実施例)
母粉末として、ガス噴霧法により得られたアスペクト比
が約5のはんだ(Pb:40重量%、Sn:60重量%
)粉末を使用し、第1図に示したような球状化装置によ
り球状化を行った。なお、この球状化装置において、高
温管状炉1の内径は1 、000mm、全高は6,00
0mmそして加熱管2の内径は60ffim。(Example) As a base powder, solder with an aspect ratio of about 5 obtained by a gas atomization method (Pb: 40% by weight, Sn: 60% by weight) was used.
) powder was used to spheronize it using a spheronizer as shown in FIG. In this spheroidization apparatus, the inner diameter of the high-temperature tubular furnace 1 is 1,000 mm, and the total height is 6,00 mm.
0mm and the inner diameter of the heating tube 2 is 60ffim.
高さは1 、000mmとし、ヒータ3は消費電力が2
0kwのものを用いた。The height is 1,000mm, and the power consumption of heater 3 is 2.
A 0kW one was used.
まず、試料ホッパ4に母粉末を収容し、加熱チャンバl
b内を真空排気したのち、窒素(Nt)ガスで置換した
。一方、ヒータ3に通電して加熱管2の温度を1,00
0℃とした。この状態で試料導入チャンバ1aにN2ガ
スを流速5i/分で導入し、母粉末に1kg/分の流下
速度を付与して、落下させた。First, the mother powder is placed in the sample hopper 4, and the heating chamber l is placed in the sample hopper 4.
After evacuating the inside of b, the atmosphere was replaced with nitrogen (Nt) gas. On the other hand, the heater 3 is energized to raise the temperature of the heating tube 2 to 1,000
The temperature was 0°C. In this state, N2 gas was introduced into the sample introduction chamber 1a at a flow rate of 5 i/min, and the base powder was allowed to fall at a flow rate of 1 kg/min.
このようにして試料回収チャンバICに捕集されたはん
だ粉末は、アスペクト比1.2〜1.5のほぼ均一な球
状粉末であった。The solder powder thus collected in the sample collection chamber IC was a substantially uniform spherical powder with an aspect ratio of 1.2 to 1.5.
(発明の効果)
以上説明したように、本発明によれば、金属もしくは合
金よりなる母粉末を、該金属もしくは合金を溶融させう
る温度に保持された高温域を通過させて一旦溶融させた
のち落下させ、この落下途中で冷却・凝固させることと
したので、通常の粉末製造法、すなわち、機械的粉砕法
、液体噴霧法およびガス噴霧法を適用して球状粉末の得
られない金属もしくは合金であっても、かかる非球状粉
末を母粉末として本発明の球状化方法を実施することに
より球状粉末を容易に得ることが可能となる。(Effects of the Invention) As explained above, according to the present invention, a base powder made of a metal or an alloy is passed through a high temperature region maintained at a temperature capable of melting the metal or alloy, and then melted. Since we decided to drop the powder and allow it to cool and solidify during the fall, we applied ordinary powder manufacturing methods, that is, mechanical crushing, liquid atomization, and gas atomization, to produce metals or alloys for which spherical powder cannot be obtained. Even if such a non-spherical powder exists, it is possible to easily obtain a spherical powder by carrying out the spheroidizing method of the present invention using such non-spherical powder as a base powder.
第1図は本発明の金属もしくは合金粉末の球状化方法を
実施する際に使用される装置の一例を示す概略構成図で
ある。
1・・・縦型高温管状炉、1a・・・試料導入チャンバ
、1b・・・加熱チャンバ、IC・・・粉末回収チャン
バ、2・・・加熱管、3・・・ヒータ、4・・・試料ホ
ッパ、8・・・真空ポンプ。FIG. 1 is a schematic configuration diagram showing an example of an apparatus used when carrying out the method for spheroidizing metal or alloy powder of the present invention. DESCRIPTION OF SYMBOLS 1... Vertical high temperature tubular furnace, 1a... Sample introduction chamber, 1b... Heating chamber, IC... Powder collection chamber, 2... Heating tube, 3... Heater, 4... Sample hopper, 8...vacuum pump.
Claims (2)
くは合金を溶融させうる温度に保持された高温域を通過
させて一旦溶融させたのち落下させ、この落下途中で冷
却・凝固させることを特徴とする金属もしくは合金粉末
の球状化方法。(1) The base powder made of a metal or alloy is passed through a high temperature range maintained at a temperature that allows the metal or alloy to melt, once melted, and then dropped, and is cooled and solidified during the fall. A method for spheroidizing metal or alloy powder.
に打ち勝って落下する流速を前記金属もしくは合金母粉
末に付与することを特徴とする特許請求の範囲第1項記
載の金属もしくは合金粉末の球状化方法。(2) The metal or alloy according to claim 1, characterized in that, when passing through the high temperature area, the metal or alloy mother powder is given a flow velocity that overcomes the rising air current generated in the high temperature area and falls. Method for spheronizing powder.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP61256922A JPS63111101A (en) | 1986-10-30 | 1986-10-30 | Spheroidizing method for metal or alloy powder |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP61256922A JPS63111101A (en) | 1986-10-30 | 1986-10-30 | Spheroidizing method for metal or alloy powder |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS63111101A true JPS63111101A (en) | 1988-05-16 |
Family
ID=17299241
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP61256922A Pending JPS63111101A (en) | 1986-10-30 | 1986-10-30 | Spheroidizing method for metal or alloy powder |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS63111101A (en) |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH01259101A (en) * | 1988-04-08 | 1989-10-16 | Nippon Steel Corp | Manufacture of ferrous spherical particle |
WO1991008850A1 (en) * | 1989-12-07 | 1991-06-27 | Nippon Steel Corporation | Method of manufacturing minute metallic balls uniform in size |
JPH0466601A (en) * | 1990-07-06 | 1992-03-03 | Nippon Steel Corp | Manufacture of fine metal balls |
US5761779A (en) * | 1989-12-07 | 1998-06-09 | Nippon Steel Corporation | Method of producing fine metal spheres of uniform size |
JP2012228631A (en) * | 2011-04-25 | 2012-11-22 | Chugai Ro Co Ltd | Falling-type powder treatment apparatus |
JP2015175041A (en) * | 2014-03-17 | 2015-10-05 | 国立大学法人東北大学 | Production method of amorphous soft magnetic alloy powder |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5684401A (en) * | 1979-12-11 | 1981-07-09 | Matsushita Electric Ind Co Ltd | Manufacture of spherical metal grain |
-
1986
- 1986-10-30 JP JP61256922A patent/JPS63111101A/en active Pending
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5684401A (en) * | 1979-12-11 | 1981-07-09 | Matsushita Electric Ind Co Ltd | Manufacture of spherical metal grain |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH01259101A (en) * | 1988-04-08 | 1989-10-16 | Nippon Steel Corp | Manufacture of ferrous spherical particle |
WO1991008850A1 (en) * | 1989-12-07 | 1991-06-27 | Nippon Steel Corporation | Method of manufacturing minute metallic balls uniform in size |
US5761779A (en) * | 1989-12-07 | 1998-06-09 | Nippon Steel Corporation | Method of producing fine metal spheres of uniform size |
JPH0466601A (en) * | 1990-07-06 | 1992-03-03 | Nippon Steel Corp | Manufacture of fine metal balls |
JP2012228631A (en) * | 2011-04-25 | 2012-11-22 | Chugai Ro Co Ltd | Falling-type powder treatment apparatus |
JP2015175041A (en) * | 2014-03-17 | 2015-10-05 | 国立大学法人東北大学 | Production method of amorphous soft magnetic alloy powder |
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