KR100689622B1 - annealing heat annealing method - Google Patents

annealing heat annealing method Download PDF

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KR100689622B1
KR100689622B1 KR1020050056677A KR20050056677A KR100689622B1 KR 100689622 B1 KR100689622 B1 KR 100689622B1 KR 1020050056677 A KR1020050056677 A KR 1020050056677A KR 20050056677 A KR20050056677 A KR 20050056677A KR 100689622 B1 KR100689622 B1 KR 100689622B1
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chamber
heat treatment
annealing
nitrogen gas
low vacuum
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KR20070001317A (en
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최윤석
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    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING 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
    • C21D1/00General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/26Methods of annealing
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING 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
    • C21D1/00General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/74Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material
    • C21D1/773Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material under reduced pressure or vacuum

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Abstract

본 발명은 금속·비금속 등을 가열하였다가 필요한 연화율이 될때 까지 서서히 식혀는 열처리의 일종인 풀림(annealing, 일명 "소둔"이라 칭하기도함)처리시 산화방지용 매질을 저원가이면서 고효율성을 보장하는 중성가스를 사용함과 동시에 극저진공(무산화) 분위기를 조성해 피열처리물의 표면산화 및 이상층 발생을 극소화함으로서 풀림열처리 대상물의 품질향상 뿐만 아니라 처리공정, 처리시간 및 원가절감은 물론 환경 친화적인 요소까지 갖춘 저진공 풀림(annealing)열처리방법을 제공코자 하는 것이다.The present invention is a neutral to ensure the high cost and high efficiency of the anti-oxidation medium at the time of annealing (also called "annealing") treatment, which is a kind of heat treatment that is slowly cooled until the required softening rate after heating the metal and nonmetal, etc. By using gas and creating a very low vacuum (no oxidation) atmosphere, it minimizes surface oxidation and abnormal layer generation of the heat-treatment, and not only improves the quality of annealing heat-treatment object, but also reduces processing process, processing time and cost, and environmentally friendly elements. To provide a low vacuum annealing heat treatment method.

즉, 풀림열처리장치(10)를 구성함에 있어서, 상기 풀림열처리장치(10)는 개페부(210) 및 일정크기와 용량의 쳄버(220)를 구비하는 열처리로(20)와, That is, in configuring the annealing heat treatment apparatus 10, the annealing heat treatment apparatus 10 includes a heat treatment furnace 20 having an opening 210 and a chamber 220 of a predetermined size and capacity;

대기중의 질소를 추출하여 쳄버(220)내로 질소가스를 1차 혹은 2차로 공급하여 주기 위한 질소발생기(30)와, 쳄버(220) 내부의 공기의 압력(진공)을 조절하여 진공환경을 조성하는데 필요한 배기펌프(40)와, 쳄버(220) 내부의 압력을 일정하게 유지시켜 주기 위한 자동 압력조절기(50)로 구성되는 것이다.Create a vacuum environment by adjusting the pressure (vacuum) of the nitrogen generator 30 and the air inside the chamber 220 to extract nitrogen in the atmosphere and supply nitrogen gas to the chamber 220 first or second. It is composed of an exhaust pump 40 and an automatic pressure regulator 50 for maintaining a constant pressure inside the chamber 220.

질소가스, 저진공, 질소발생기, 배기펌프, 쳄버 Nitrogen Gas, Low Vacuum, Nitrogen Generator, Exhaust Pump, Chamber

Description

저진공 풀림열처리방법{annealing heat annealing method}Low vacuum annealing method

도 1은 본 발명에서 제시하는 풀림열처리장치의 설치 구성도.1 is an installation configuration of the annealing heat treatment apparatus proposed in the present invention.

▣ 도면의 주요부분에 사용된 부호의 설명 ▣▣ Explanation of symbols used in main part of drawing

10:풀림열처리장치 20:열처리로10: annealing heat treatment device 20: heat treatment furnace

30:질소발생기 40:배기펌프30: nitrogen generator 40: exhaust pump

50:자동 압력조절기 210:개페부50: Automatic pressure regulator 210: Opening part

220:쳄버220: Chamber

본 발명은 금속·비금속 등을 가열하였다가 필요한 연화율이 될때 까지 서서히 식혀는 열처리의 일종인 풀림(annealing, 일명 "소둔"이라 칭하기도함)처리시 산화방지용 매질을 저원가이면서 고효율성을 보장하는 중성가스를 사용함과 동시에 극저진공(무산화) 분위기를 조성해 피열처리물의 표면산화 및 이상층 발생을 극소화함으로서 풀림열처리 대상물의 품질향상 뿐만 아니라 처리공정, 처리시간 및 원가절감은 물론 환경 친화적인 요소까지 갖춘 저진공 풀림(annealing)열처리방법을 제공코자하는 것이다.The present invention is a neutral to ensure the high cost and high efficiency of the anti-oxidation medium at the time of annealing (also referred to as annealing), which is a kind of heat treatment that gradually cools down to a required softening rate after heating a metal or a nonmetal. By using gas and creating a very low vacuum (no oxidation) atmosphere, it minimizes surface oxidation and abnormal layer generation of the heat-treatment, and not only improves the quality of annealing heat-treatment object, but also reduces processing process, processing time and cost, and environmentally friendly elements. To provide a low vacuum annealing heat treatment method.

통상의 풀림(annealing) 또는 소둔설비는 금속소재의 단조시에 발생한 응력을 제거하기 위한 열처리기법 중 하나의 설비로서, Conventional annealing or annealing equipment is one of the heat treatment techniques to remove the stress generated during forging of metal materials,

열처리대상체를 소정크기의 로에 장입하여 밀폐시킨 후 그 로내의 온도를 서서히 승온시켜 일정온도의 승온(통상 600℃ ~ 850℃ 내,외)이 이루어지도록 한 다음, After charging the heat-treatment object in a furnace of a predetermined size and sealing it, the temperature in the furnace is gradually raised to allow a certain temperature to be raised (usually within 600 ℃ ~ 850 ℃).

그 열처리대상체의 크기나 용도, 재질적 특성 등에 따른 요구 연성율에 도달할때 까지 서서히 냉각(로냉각, 자연냉각, 강제냉각 등)처리를 하게 된다.Cooling (low cooling, natural cooling, forced cooling, etc.) is gradually performed until the required ductility ratio is reached according to the size, use, and material properties of the heat treatment object.

그런데 상기 열처리로내에서 승온되는 동안 잔류하는 공기로 인해 열처리 대상체의 표면이 산화를 일으키거나 미세 이상층이 발생될 뿐 아니라 승온후에도 계속적인 표면산화가 발생하기 때문에,However, due to the air remaining during the temperature increase in the heat treatment furnace, not only the surface of the heat treatment object is oxidized or a fine abnormality layer is generated, but also the surface oxidation continuously occurs after the temperature rise,

종래에는 이를 막기위해 고가인 메틸알콜을 승온시 풀림 열처리로에 주입하여 사용해 왔다.Conventionally, to prevent this, expensive methyl alcohol has been used by injecting it into an annealing heat treatment furnace at an elevated temperature.

그러나 상기한 메틸알콜은 상당한 고가일 뿐 아니라 사용 후 대기 중으로 배출되는 메틸알콜로 인해 대기를 오염시키는 원인으로 작용하는 문제점이 있고,However, the above-described methyl alcohol is not only expensive, but also serves as a cause of polluting the air due to methyl alcohol discharged into the atmosphere after use,

또, 산화방지를 위해 사용되는 메틸알콜은 제품에 좋지 않은 영향을 줄 수 있을 뿐만 아니라 일정온도로 승온이 이루어진 다음 주입되므로 산화방지라는 소기의 목적을 보다 완벽하게 달성하는데는 역부족한 문제점이 있으며,In addition, methyl alcohol, which is used for the oxidation, may not only adversely affect the product, but also is injected after the temperature is raised to a certain temperature, and thus there is a problem in that it is insufficient to achieve the desired purpose of the oxidation prevention more perfectly.

또, 메틸알콜 사용 및 취급시 수반되는 열악한 작업환경적 요인으로 3D 기피현상에 따른 인력확충에도 큰 어려움이 야기되는 문제점까지 있어왔다.In addition, due to the poor working environment factors involved in the use and handling of methyl alcohol, there has been a problem that causes a great difficulty in expanding manpower due to the 3D evasion phenomenon.

더군다나 상기 종래의 풀림열처리설비를 이용하여 열처리 공정이 가해진 제품은 상당한 에너지를 소모함과 동시에 공정 및 시간동안 열처리를 했음에도 불구하고 상술된 바와 같이 열처리대상체의 표면 산화를 완벽히 방지하지 못함에 따라 또 다시 2차 열처리(후처리)가공공정을 추가로 거쳐야 하므로 막대한 에너지및 공정기간의 낭비를 유발할 수밖에 없다.Furthermore, the product subjected to the heat treatment process using the conventional annealing heat treatment equipment consumes a considerable amount of energy and at the same time does not completely prevent surface oxidation of the heat treatment object as described above despite the heat treatment during the process and time. Secondary heat treatment (post-treatment) processing must be additionally processed, which leads to a waste of enormous energy and processing time.

이러한 제반문제점은 결과적으로 제품의 원가를 상승시키는 주요인으로 작용하여 가격경쟁력 약화로 이어지는 중대한 문제로 이어짐으로 이의 해결이 시급한 실정이다.This problem is urgently needed to solve this problem as a major factor that increases the cost of the product, which leads to a serious problem that leads to a weak price competitiveness.

이에 본 발명에서는 전술한 바와 같은 종래 풀림열처리방법이 가지는 제반 문제점을 일소하기 위해 창안한 것으로서, 풀림 열치리 대상체에 발생될 수 있는 산화 및 이상층의 발생을 근본적이고 원천적으로 방지할 수 있도록 저진공분위기를 조성함과 동시에 대기중에 78%를 차지하는 가스 일뿐 아니라 화학적으로 불연성이고 대단히 안정된 산화방지 기능을 가진 질소가스를 사용하여 완벽한 무산화분위기를 유도함에 주안점을 두고 그 기술적 과제로서 완성한 것이다.Therefore, the present invention was devised to eliminate all the problems of the conventional annealing heat treatment method as described above, and low vacuum so as to fundamentally and fundamentally prevent the occurrence of oxidation and an abnormal layer that may occur in the annealing heat treatment object. At the same time, it is a technical task that focuses on inducing a perfect atmosphere without using oxygen gas, which is 78% in the atmosphere, as well as chemically incombustible and highly stable antioxidant.

위 기술적 과제를 달성하기 위해 본원에서는 첨부된 각 도면에 의거 보다 상세히 설명하면 하기와 같다. In order to achieve the above technical problem, the present disclosure will be described in more detail based on the accompanying drawings.

도 1에 본 발명에서 제시하는 풀림열처리장치가 도시되는데, 도시된 바를 통해 본 발명은 풀림열처리공정과, 풀림열처리장치를 포함하는 것임을 알 수 있다.Figure 1 shows the annealing heat treatment apparatus proposed in the present invention, it can be seen that the present invention includes an annealing heat treatment process, and an annealing heat treatment apparatus.

먼저, 본 발명의 풀림열처리공정은,First, the annealing heat treatment step of the present invention,

풀림열처리하기 위한 대상물을 쳄버에 장입한 다음 쳄버를 밀폐시킨 상태에서 배기수단을 이용해 쳄버 내부의 압력을 최소 대기압이하(원가적 측면 등을 고려 700 ~ 750 Torr가 적당함)의 범위로 조절하는 저진공처리단계와;Insert the object for heat treatment into the chamber, and then use the venting means to adjust the pressure inside the chamber to the minimum atmospheric pressure (700 ~ 750 Torr is appropriate considering the cost side, etc.). A vacuum treatment step;

저진공분위기의 쳄버내로 대기중에 78%를 차지하고 화학적으로 불연성이라 안전성이 보장됨은 물론 대단히 안정되고 완벽한 산화방지기능을 가진 질소가스를 주입하는 1차 질소가스주입단계와;A first nitrogen gas injection step of injecting nitrogen gas into the chamber in a low vacuum atmosphere, occupying 78% in the atmosphere, chemically incombustible, and ensuring safety, as well as having a very stable and perfect antioxidant function;

이후 가열수단을 이용해 쳄버내의 온도가 열처리대상체가 가지는 변태점 이하의 온도(재질의 종류, 크기 등의 특성에 따라 크게 다르나 대개 600℃~ 850℃ 정 도가 적합함)로 승온시키는 승온단계와;A heating step of raising the temperature of the chamber to a temperature below the transformation point of the heat treatment object (which varies greatly depending on the type of material, size, etc., but is generally 600 ° C. to 850 ° C.) using a heating means;

이때 또 다시 질소가스를 쳄버내 압력이 대기압 보다 약간 높은 770 ~ 790Torr가 되도록 2차로 더 주입하여 쳄버내에 산화방지용질소가스 함량이 높아 열처리 대상체표면에 접근하는 산소를 보다 근본적으로 차단하는 2차 질소가스주입단계; 를 거처 후 처리공정인 냉각공정을 통해 완료되는 것으로 포함한 것이다.At this time, nitrogen gas is further injected into the chamber so that the pressure in the chamber is 770 to 790 Torr, which is slightly higher than atmospheric pressure, so that the nitrogen gas for oxidation is higher in the chamber. Injection step; It is included as being completed through the cooling process, which is a post-treatment process.

이하, 위 풀림열처리방법을 수행하기 위해 사용될 수 있는 풀림열처리장치(10)는,Hereinafter, the annealing heat treatment apparatus 10 that can be used to perform the above annealing heat treatment method,

개페부(210) 및 일정크기와 용량의 쳄버(220)를 구비하는 열처리로(20)와, A heat treatment furnace (20) having an opening (210) and a chamber (220) of constant size and capacity;

대기중의 질소를 추출하여 쳄버(220)내로 질소가스를 1차 혹은 2차로 공급하여 주기 위한 질소발생기(30)와, A nitrogen generator 30 for extracting nitrogen from the atmosphere and supplying nitrogen gas to the chamber 220 in a primary or secondary manner,

쳄버(220) 내부의 공기의 압력(진공)을 조절하여 진공환경을 조성하는데 필요한 배기펌프(40)와, An exhaust pump 40 necessary to adjust the pressure (vacuum) of the air inside the chamber 220 to create a vacuum environment,

쳄버(220) 내부의 압력을 일정하게 유지시켜 주기 위한 자동 압력조절기(50) 의 구성요소로 이루어지는 것이다.It is made of a component of the automatic pressure regulator 50 for maintaining a constant pressure in the chamber 220.

이상과 같이 본 발명의 풀림열처리방법 및 그 장치는 쳄버내의 산화방지용 매질로서 특히 대기중에 78%를 차지하는 가스 일뿐 아니라 화학적으로 불연성이라 안전성이 보장되며, 대단히 안정된 산화방지 기능을 가지고 있는 천연질소가스를 사용함에 따라 ,As described above, the annealing heat treatment method and apparatus of the present invention is an oxidation medium in the chamber, which is not only gas which occupies 78% in the atmosphere, but also chemically incombustible, which ensures safety and provides natural nitrogen gas having a very stable antioxidant function. As you use

고가인 메틸알콜을 사용하는 기존에 비해 막대한 에너지 대체 효과를 기대할 수 있을 뿐 아니라,Not only can we expect an enormous energy replacement effect compared to the existing expensive methyl alcohol,

대기중의 가스를 즉시 축출하여 사용함 따라 저원가 및 공급의 원활성이 제공됨은 물론 사용된 질소가스를 다시 대기로 방출하더라도 공해를 일으키기 않는 등의 친환경적요소까지 제공되는 이점이 있고,By expelling and using the gas in the air immediately, it provides the low cost and the smoothness of supply, and also provides the eco-friendly elements such as not causing pollution even when the used nitrogen gas is released back to the atmosphere.

무엇보다 저진공 및 질소분위기에 기인하여 한번의 풀림공정으로 열처리 대상체의 표면산화를 근본적이고 원천적으로 차단함에 따라 저원가로서 보다 우수한 고품질 열처리기법이라 할 수 있다.Above all, due to the low vacuum and nitrogen atmosphere, it can be said to be a high quality heat treatment technique that is superior at low cost as it fundamentally blocks the surface oxidation of the heat treatment object by one annealing process.

나아가 본 발명은 질소를 질소발생기에서 즉시 발생 후 쳄버내로 주입 사용하기 때문에 아주 청결한 작업환경조성에도 크게 기여할 수 있고,Furthermore, the present invention can contribute greatly to the creation of a very clean working environment because nitrogen is injected into the chamber immediately after generation from the nitrogen generator,

더 나아가 본 발명은 열처리 이후 수반되었던 2차 열처리(후처리) 공정을 생략할 수 있기 때문에 절감되는 공정 및 기타 비용은 더욱 커 국가적인 기술 및 수출가격경쟁력에서 크게 우의를 점할 수 있는 등 대단히 우수한 발명이라 할 수 있다.Furthermore, the present invention can omit the secondary heat treatment (post-treatment) process that has been carried out after the heat treatment, so that the process and other costs saved are much greater and can greatly favor national technology and export price competitiveness. This can be called.

이상에서 상세히 살펴본 본 발명의 풀림열처리방법은 풀림열처리 대상체의 품질을 대폭 향상시킬 수 있을 뿐 아니라 보다 저렴한 원가로 처리가능 함은 물론 에너지 대체 효과 및 친환경성, 작업환경개선의 효과까지 제공되는 등 우수한 발명이다.The annealing heat treatment method of the present invention described in detail above can not only significantly improve the quality of annealing heat treatment objects, but also can be processed at a lower cost, and also provide excellent energy replacement effects, eco-friendliness, and improvement of working environment. Invention.

Claims (2)

금속 및 비금속 등을 풀림열처리함에 있어서,In annealing heat treatment of metals and nonmetals, 열처리 대상물을 쳄버에 장입한 다음 쳄버를 밀폐시킨 상태에서 배기수단을 이용해 쳄버 내부의 압력을 최소 700 ~ 750 Torr의 대기압 이하 범위로 조절하는 저진공처리단계와;A low vacuum treatment step of charging a heat treatment object to a chamber and then adjusting the pressure inside the chamber to an atmospheric pressure range of at least 700 to 750 Torr by using an exhaust means while the chamber is sealed; 저진공분위기의 쳄버내로 대기중에 78%를 차지하고 저렴할 뿐 아니라 화학적으로 불연성이라 안전성이 보장됨은 물론 대단히 안정되고 완벽한 산화방지기능을 가진 질소가스를 주입하는 1차 질소가스주입단계와;A first nitrogen gas injection step of injecting nitrogen gas into a chamber in a low vacuum atmosphere, occupying 78% in the atmosphere, inexpensive, chemically incombustible, and ensuring safety, as well as having a very stable and perfect antioxidant function; 이후 가열수단을 이용해 쳄버내의 온도가 열처리대상체가 가지는 변태점 이하의 온도인 600℃~ 850℃로 승온시키는 승온단계와;A heating step of raising the temperature of the chamber to 600 ° C. to 850 ° C., which is a temperature below the transformation point of the heat treatment object using a heating means; 이때 또 다시 질소가스를 쳄버내 압력이 대기압 보다 높은 770 ~ 790Torr가 되도록 2차로 더 주입하여 쳄버내에 산화방지용질소가스 함량이 높아 열처리 대상체표면에 접근하는 산소를 보다 근본적으로 차단하는 2차 질소가스주입단계; 를 포함하여 이루어지는 것을 특징으로 한 저진공 풀림열처리처리방법.At this time, nitrogen gas is further injected into the chamber so that the pressure in the chamber is 770 to 790 Torr higher than the atmospheric pressure, and the secondary nitrogen gas injection which fundamentally blocks oxygen approaching the surface of the heat treatment object due to the high content of antioxidant nitrogen gas in the chamber. step; Low vacuum annealing heat treatment method comprising a. 삭제delete
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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20010068737A (en) * 2000-01-08 2001-07-23 박천일 heat treatment method of stainless-steel
KR20030045767A (en) * 2003-05-24 2003-06-11 박옥실 annealing process to purge a oxygen
KR20040058830A (en) * 2002-12-27 2004-07-05 주식회사 포스코 Annealing and continuous descaling method of ferritic stainless steel

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20010068737A (en) * 2000-01-08 2001-07-23 박천일 heat treatment method of stainless-steel
KR20040058830A (en) * 2002-12-27 2004-07-05 주식회사 포스코 Annealing and continuous descaling method of ferritic stainless steel
KR20030045767A (en) * 2003-05-24 2003-06-11 박옥실 annealing process to purge a oxygen

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