JPS644565B2 - - Google Patents
Info
- Publication number
- JPS644565B2 JPS644565B2 JP18247384A JP18247384A JPS644565B2 JP S644565 B2 JPS644565 B2 JP S644565B2 JP 18247384 A JP18247384 A JP 18247384A JP 18247384 A JP18247384 A JP 18247384A JP S644565 B2 JPS644565 B2 JP S644565B2
- Authority
- JP
- Japan
- Prior art keywords
- gas
- furnace
- temperature
- annealing
- reducing
- 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
Links
- 238000000137 annealing Methods 0.000 claims description 15
- 238000000034 method Methods 0.000 claims description 11
- 229910000831 Steel Inorganic materials 0.000 claims description 8
- 239000010959 steel Substances 0.000 claims description 8
- 239000007789 gas Substances 0.000 description 48
- 238000005261 decarburization Methods 0.000 description 9
- 238000006243 chemical reaction Methods 0.000 description 8
- 238000006722 reduction reaction Methods 0.000 description 8
- 238000010438 heat treatment Methods 0.000 description 4
- 229910052799 carbon Inorganic materials 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- 229910000975 Carbon steel Inorganic materials 0.000 description 2
- 239000010962 carbon steel Substances 0.000 description 2
- 229930195733 hydrocarbon Natural products 0.000 description 2
- 150000002430 hydrocarbons Chemical class 0.000 description 2
- 230000007935 neutral effect Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 235000008733 Citrus aurantifolia Nutrition 0.000 description 1
- 235000011941 Tilia x europaea Nutrition 0.000 description 1
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000004571 lime Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 238000011946 reduction process Methods 0.000 description 1
- 102200082816 rs34868397 Human genes 0.000 description 1
- 239000000344 soap Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/74—Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Heat Treatment Of Strip Materials And Filament Materials (AREA)
Description
【発明の詳細な説明】
〔産業上の利用分野〕
この発明は、鉄鋼処理品の無脱炭焼なまし方法
に関し、とくに、処理品を焼なまし処理する前
に、炉内温度を400〜600℃に保持してH2ガスも
しくはH2を含有するガスを流しながら炉内の雰
囲気ガスを循環させて水分を除去し、炉内雰囲気
ガスの露点を20℃以下に調整保持して処理品の酸
化物を還元処理することにより、炉内温度を焼な
まし処理温度に昇温する過程と焼なまし処理時に
脱炭反応を防止するようにしたものである。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for non-decarburization annealing of processed steel products, and in particular, before annealing the processed products, the furnace temperature is increased to 400 to 600°C. ℃ and circulate the atmospheric gas in the furnace while flowing H 2 gas or gas containing H 2 to remove moisture.The dew point of the furnace atmosphere gas is adjusted and maintained at 20℃ or less and the processed products are heated. By reducing the oxide, decarburization reactions are prevented during the process of raising the temperature inside the furnace to the annealing temperature and during the annealing process.
一般に、炭素鋼線材等の焼なまし処理を行う場
合、処理品の表面には酸化スケールが付着してお
り、またボンデライト処理、石灰処理、金属石け
ん添加等が行われるため、600℃以上の温度に加
熱されると脱炭性の雰囲気ガスが発生する。これ
らの雰囲気ガスによる脱炭反応を防止するため、
従来の焼なまし処理においては、中性ガスあるい
は還元性ガスを炉内に流しながら加熱処理する方
法が行われている。たとえばN2ガス、N2＋RX
ガス、NXガス等が用いられている。
Generally, when annealing carbon steel wire rods, etc., oxidized scale is attached to the surface of the treated product, and bonderite treatment, lime treatment, addition of metal soap, etc. are performed, so temperatures of 600℃ or higher When heated to , a decarburizing atmospheric gas is generated. In order to prevent decarburization reactions caused by these atmospheric gases,
In conventional annealing treatment, a method is performed in which heat treatment is performed while flowing a neutral gas or reducing gas into a furnace. For example, N 2 gas, N 2 +RX
Gas, NX gas, etc. are used.
酸化物（Fe3O4、FeO、Fe2O3）が付着した鉄
鋼処理品を加熱処理する場合、炉内の雰囲気ガス
を還元性に保つためには一般にH2ガス、COガ
ス、またはこれらを含む混合ガス、炭化水素を含
む混合ガスが使用される。これらのガスは処理品
に付着した酸化物と還元反応を生じて、下記式に
よりH2O、CO2を発生する。
When heat treating steel products with adhering oxides (Fe 3 O 4 , FeO, Fe 2 O 3 ), H 2 gas, CO gas, or these gases are generally used to keep the atmospheric gas in the furnace reducing. A mixed gas containing hydrocarbons and a mixed gas containing hydrocarbons are used. These gases cause a reduction reaction with oxides attached to the processed product, and generate H 2 O and CO 2 according to the following formula.
FeO＋COFe＋CO2
Fe3O4＋CO3FeO＋CO2
Fe3O4＋4CO3Fe＋4CO2
FeO＋H2Fe＋H2O
Fe3O4＋H23FeO＋H2O
Fe3O4＋4H23Fe＋4H2O
上記の還元反応を右側に進行させるためには、
H2ガス、COガスを供給し、反応によつて生ずる
H2O、CO2を除去する必要があるが、従来はH2
ガス、COガスを含むガスを処理時間中に連続し
て供給して、生成されたH2O、CO2を炉外に放出
しているため、還元性ガスの消費量がきわめて多
量となり、コスト高となるのを免れない欠点があ
る。 FeO+COFe+CO 2 Fe 3 O 4 +CO3FeO+CO 2 Fe 3 O 4 +4CO3Fe+4CO 2 FeO+H 2 Fe+H 2 O Fe 3 O 4 +H 2 3FeO+H 2 O Fe 3 O 4 +4H 2 3Fe+4H 2 O To make the above reduction reaction proceed to the right,
H2 gas, CO gas is supplied and produced by the reaction
It is necessary to remove H 2 O, CO 2 , but conventionally H 2
Because gas containing gas and CO gas is continuously supplied during the processing time and the generated H 2 O and CO 2 are released outside the furnace, the amount of reducing gas consumed is extremely large, resulting in high costs. There is an unavoidable drawback that it is expensive.
また、低温でCO含有量の多いガスを流す場合
には、炉内がスーテイングすることがあり、その
後の昇温で処理品に浸炭させてしまうなどの技術
的欠点がある。 In addition, when flowing gas with a high CO content at low temperatures, there may be sooting inside the furnace, which has technical drawbacks such as carburization of the processed product due to subsequent temperature rise.
この発明は、上記の欠点を解消して、必要最小
限の還元性ガスを使用して技術的に確実で容易な
無脱炭組織の処理品が得られる焼なまし方法を提
供することを目的とする。 The purpose of the present invention is to eliminate the above-mentioned drawbacks and provide an annealing method that uses the minimum necessary reducing gas to obtain a technically reliable and easily processed product with a non-decarburized structure. shall be.
還元反応は、400℃以下ではCOまたはH2の分
圧をかなり高くしなければならず、また還元力も
弱いので好ましくない。したがつて、還元処理は
400℃以上の温度で行う必要がある。
The reduction reaction is not preferable at temperatures below 400°C, as the partial pressure of CO or H 2 must be considerably high, and the reducing power is also weak. Therefore, the reduction process is
It is necessary to carry out at a temperature of 400℃ or higher.
また、酸化物の付着した処理品をCO2ガス、
H2Oガスの雰囲気で加熱処理すると、下記式の
脱炭反応が生ずる。 Additionally, treated products with oxides attached can be removed using CO 2 gas,
When heat treated in an atmosphere of H 2 O gas, the following decarburization reaction occurs.
〔Ｃ〕＋CO22CO
〔Ｃ〕＋H2OCO＋H2
ただし、〔Ｃ〕は鋼中の炭素
上記式の脱炭反応は、600℃以上の温度から始
まるから、この温度に上昇するまでの間に酸化物
の還元反応を完了させる必要がある。 [C] + CO 2 2CO [C] + H 2 OCO + H 2 However, [C] is the carbon in the steel. The decarburization reaction in the above formula starts at a temperature of 600°C or higher, so the oxidation occurs until the temperature rises to this temperature. It is necessary to complete the reduction reaction of a substance.
この発明においては、上記の温度範囲で酸化物
の還元反応を終了させるに当たり、H2ガスまた
はH2を含有する混合ガスを炉内に導入しながら
炉内の雰囲気ガスを循環させて、炉内の露点が20
℃以下となるまで水分を除去した後、炉内温度を
焼なまし処理温度まで昇温させるようにしてい
る。 In this invention, in order to complete the reduction reaction of the oxide in the above temperature range, the atmospheric gas in the furnace is circulated while introducing H 2 gas or a mixed gas containing H 2 into the furnace. dew point of 20
After removing moisture until the temperature is below 0.degree. C., the temperature inside the furnace is raised to the annealing temperature.
なお、炉内雰囲気ガスの露点を20℃以下にする
理由は、炉内温度が400〜600℃の範囲において、
処理品、すなわち鋼中の炭素と炉内雰囲気中の
H2Oとの反応が脱炭反応を起こさず、また鋼に
対して酸化反応を起こさない還元領域中に炉内雰
囲気を調節する必要性があるためである。 The reason why the dew point of the furnace atmosphere gas is set to 20℃ or less is that when the furnace temperature is in the range of 400 to 600℃,
The carbon in the processed product, i.e. the steel, and the atmosphere in the furnace
This is because it is necessary to adjust the atmosphere in the furnace to a reduction region where the reaction with H 2 O does not cause a decarburization reaction and does not cause an oxidation reaction to the steel.
この発明の方法を実施する装置を第１図に示
す。同図において、符号１０は炉体、１２はH2
ガス導入管、１４は復圧用の液体N2導入管、１
６は炉内圧力を一定に保つためのリリーフ弁であ
る。
An apparatus for carrying out the method of the invention is shown in FIG. In the figure, numeral 10 is a furnace body, 12 is an H 2
Gas introduction pipe, 14 is liquid N 2 introduction pipe for pressure recovery, 1
6 is a relief valve for keeping the pressure inside the furnace constant.
上記の炉体１０には、冷却機１８が連結され、
冷却機１８に内蔵されたポンプにより、炉内の雰
囲気ガスを吸引して循環させ、雰囲気ガスの露点
が20℃以下となるまで炉内の水分を除去するよう
にしいてる。 A cooler 18 is connected to the furnace body 10,
A pump built into the cooler 18 sucks and circulates the atmospheric gas in the furnace to remove moisture in the furnace until the dew point of the atmospheric gas becomes 20° C. or less.
次に、この発明の方法による加熱処理の一例
を、第２図のタイムチヤートによつて説明する。 Next, an example of the heat treatment according to the method of the present invention will be explained with reference to the time chart of FIG.
まず、常温で炉内を真空引きして約１〜2Torr
に減圧した後、液体N2を導入して大気圧よりや
や高い圧力まで復圧する。次いで昇温を開始し、
炉内温度が約250℃に達した時点から、H2ガスを
導入する。これと同時に冷却機の運転を開始して
冷却機に内蔵されているポンプにより炉内の雰囲
気ガスを循環させながら冷却するとともに除水し
て、炉内の露点を20℃とする。この間、H2ガス
は1.8m3/hrの流量を導入し、７〜８時間経過後
に、炉内温度を450〜550℃に昇温し、この温度で
３〜４時間保持させた後、H2ガスの導入と雰囲
気ガスの循環とを停止する。上記の雰囲気ガスの
循環によつて炉内が負圧になると、自動的にリリ
ーフ弁が作動し、液体N2を導入して復圧する。
以上によつて、処理品に付着している酸化物の還
元反応が終了する。 First, vacuum the inside of the furnace at room temperature to approximately 1 to 2 Torr.
After reducing the pressure to , liquid N 2 is introduced to restore the pressure to slightly higher than atmospheric pressure. Then start raising the temperature,
When the temperature inside the furnace reaches approximately 250°C, H2 gas is introduced. At the same time, the cooler starts operating, and the pump built into the cooler circulates the atmospheric gas inside the furnace to cool it down and remove water, bringing the dew point inside the furnace to 20°C. During this time, H 2 gas was introduced at a flow rate of 1.8 m 3 /hr, and after 7 to 8 hours, the temperature inside the furnace was raised to 450 to 550 °C, and after being maintained at this temperature for 3 to 4 hours, H 2 gas was introduced at a flow rate of 1.8 m 3 /hr. 2 Stop the introduction of gas and the circulation of atmospheric gas. When the pressure inside the furnace becomes negative due to the above-mentioned circulation of atmospheric gas, the relief valve automatically operates and liquid N 2 is introduced to restore the pressure.
Through the above steps, the reduction reaction of the oxides adhering to the processed product is completed.
続いて炉内温度を球状化処理温度（680〜760
℃）まで昇温させて５〜15時間保持し、処理品を
加熱処理する。 Next, the furnace temperature was adjusted to the spheroidization temperature (680 to 760
℃) and held for 5 to 15 hours to heat-treat the treated product.
処理品の加熱処理の終了後は、炉内温度を20
℃／ｈｒの割合で降温させ、600℃に降温した時点か
ら強制冷却して炉内温度を550℃とした後、処理
品を炉内から取り出す。 After finishing the heat treatment of the processed product, the temperature inside the furnace should be lowered to 20℃.
The temperature is lowered at a rate of 0.degree. C./hr, and after the temperature has dropped to 600.degree. C., forced cooling is performed to bring the temperature inside the furnace to 550.degree. C., and then the treated product is taken out from the furnace.
実施例
石灰水に浸漬した後、伸線を行つた酸化膜10μ
ｍある炭素鋼線材（S45C）10tonを処理品とし
て、上記実施例の処理条件で球状化焼なまし処理
したものについて、脱炭層の有無を測定し結果に
よると、この線材には脱炭がないことが確認され
た。Example: 10μ oxide film immersed in lime water and then wire drawn
The presence or absence of a decarburized layer was measured for a 10 ton carbon steel wire rod (S45C) that was subjected to spheroidizing annealing under the processing conditions of the above example, and the results showed that there was no decarburization in this wire rod. This was confirmed.
なお、酸化膜が３〜10μｍある線材を、従来の
方法で球状化焼なまし処理した場合は、0.10mmの
脱炭層が形成された。 Note that when a wire rod with an oxide film of 3 to 10 μm was subjected to spheroidizing annealing treatment using the conventional method, a decarburized layer of 0.10 mm was formed.
以上説明したように、この発明によれば、鉄鋼
処理品の酸化物の還元処理過程中にH2ガスまた
はH2を含有する混合ガスを導入しながら雰囲気
ガスを循環して炉内露点を20℃以下とした後に、
焼なまし処理温度まで昇温させるようにしている
から、必要最小限の還元性ガスを使用して脱炭反
応を生ずることのない加熱処理を行うことがで
き、中性ガスあるいは還元性ガスの消費量を大幅
に低減して安価で技術的に確実で容易な無脱炭焼
なまし処理が可能となる。
As explained above, according to the present invention, during the process of reducing oxides of steel processed products, the atmospheric gas is circulated while introducing H 2 gas or a mixed gas containing H 2 to lower the dew point in the furnace to 20. After lowering the temperature to below ℃,
Since the temperature is raised to the annealing temperature, it is possible to perform heat treatment without causing a decarburization reaction using the minimum necessary reducing gas, and without using neutral gas or reducing gas. This enables a non-decarburization annealing process that is inexpensive, technically reliable, and easy, with a significant reduction in consumption.
第１図は、この発明の方法に使用する装置を示
すブロツク図、第２図はこの発明の実施例を示す
タイムチヤートである。
図中、１０は炉体、１２はH2ガス導入管、１
８は冷却機である。
FIG. 1 is a block diagram showing an apparatus used in the method of this invention, and FIG. 2 is a time chart showing an embodiment of this invention. In the figure, 10 is the furnace body, 12 is the H 2 gas introduction pipe, 1
8 is a cooler.
Claims (1)
炉内温度を焼なまし処理温度まで昇温させる前
に、炉内温度を400〜600℃に保持したH2ガスま
たはH2を含有する混合ガスを導入しながら炉内
の雰囲気ガスを循環させて水分を除去し、炉内雰
囲気ガスの露点を20℃以下にして処理品の酸化物
を還元処理することを特徴とする鉄鋼処理品の無
脱炭焼なまし方法。1 When annealing processed steel products,
Before raising the temperature in the furnace to the annealing treatment temperature, the atmospheric gas in the furnace is circulated while introducing H 2 gas or a mixed gas containing H 2 with the furnace temperature maintained at 400 to 600 °C. A method for non-decarburizing annealing of processed steel products, characterized by removing moisture and reducing oxides in the processed products by reducing the dew point of atmospheric gas in the furnace to 20°C or less.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18247384A JPS6160820A (en) | 1984-08-31 | 1984-08-31 | Method for subjecting treated steel article to nondecarburization annealing |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18247384A JPS6160820A (en) | 1984-08-31 | 1984-08-31 | Method for subjecting treated steel article to nondecarburization annealing |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6160820A JPS6160820A (en) | 1986-03-28 |
| JPS644565B2 true JPS644565B2 (en) | 1989-01-26 |
Family
ID=16118879
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP18247384A Granted JPS6160820A (en) | 1984-08-31 | 1984-08-31 | Method for subjecting treated steel article to nondecarburization annealing |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6160820A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09216850A (en) * | 1996-02-09 | 1997-08-19 | Mitsubishi Rayon Co Ltd | Production of carboxylic acid ester |
| JP3897274B2 (en) * | 1999-12-28 | 2007-03-22 | 日立金属株式会社 | Hardening method for steel |
-
1984
- 1984-08-31 JP JP18247384A patent/JPS6160820A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6160820A (en) | 1986-03-28 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3176374B2 (en) | Method for producing low carbon molten steel by vacuum degassing decarburization | |
| ATE16118T1 (en) | PROCESS FOR HEAT TREATMENT OF METAL WORKPIECES BY CARBURIZING. | |
| JPS644565B2 (en) | ||
| GB933873A (en) | Method of producing grain oriented electrical steel | |
| US2231009A (en) | Heat treating process | |
| US3166841A (en) | Descaling | |
| US5167735A (en) | Process for the annealing of steel annealing material | |
| JPH0737645B2 (en) | Decarburization suppression method for high carbon chrome bearing steel | |
| JPH09170002A (en) | Iron powder finish heat-treating method and device therefor | |
| US5785773A (en) | Process for avoiding stickers in the annealing of cold strip | |
| US1358810A (en) | Process of treating magnetizable material | |
| US3562025A (en) | Descaling copper rods | |
| JPS6249330B2 (en) | ||
| JPS5980713A (en) | Heat treatment of steel product accompanied by no decarburization | |
| JPS5582729A (en) | Heat treating method for steel material | |
| US2595991A (en) | Annealing | |
| JPS6214008B2 (en) | ||
| JPH01176065A (en) | Gas carburizing heat treatment | |
| JPS5681629A (en) | Continuous annealing method of cold-rolled steel plate | |
| JPS6237692B2 (en) | ||
| JPS60190520A (en) | Method for heating grain-oriented electrical steel slab | |
| JP2761114B2 (en) | Annealing method for stainless steel sheet | |
| JPH0730389B2 (en) | Annealing method | |
| JPH0619102B2 (en) | Ultra low carbon steel melting method | |
| SU1073334A1 (en) | Method of chemical/heat treatment of rolled stock |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |