KR20010089944A - Heat-processing method of metal materials - Google Patents

Heat-processing method of metal materials Download PDF

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KR20010089944A
KR20010089944A KR1020000013164A KR20000013164A KR20010089944A KR 20010089944 A KR20010089944 A KR 20010089944A KR 1020000013164 A KR1020000013164 A KR 1020000013164A KR 20000013164 A KR20000013164 A KR 20000013164A KR 20010089944 A KR20010089944 A KR 20010089944A
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cooling
metal material
temperature
minutes
polishing
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KR1020000013164A
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Korean (ko)
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KR100349809B1 (en
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이규상
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이규상
(주)현광금속개발
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    • A—HUMAN NECESSITIES
    • A01—AGRICULTURE; FORESTRY; ANIMAL HUSBANDRY; HUNTING; TRAPPING; FISHING
    • A01G—HORTICULTURE; CULTIVATION OF VEGETABLES, FLOWERS, RICE, FRUIT, VINES, HOPS OR SEAWEED; FORESTRY; WATERING
    • A01G25/00—Watering gardens, fields, sports grounds or the like
    • A01G25/02—Watering arrangements located above the soil which make use of perforated pipe-lines or pipe-lines with dispensing fittings, e.g. for drip irrigation
    • A01G25/023—Dispensing fittings for drip irrigation, e.g. drippers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L11/00—Hoses, i.e. flexible pipes
    • F16L11/04—Hoses, i.e. flexible pipes made of rubber or flexible plastics
    • F16L11/08—Hoses, i.e. flexible pipes made of rubber or flexible plastics with reinforcements embedded in the wall
    • F16L11/081—Hoses, i.e. flexible pipes made of rubber or flexible plastics with reinforcements embedded in the wall comprising one or more layers of a helically wound cord or wire
    • F16L11/083—Hoses, i.e. flexible pipes made of rubber or flexible plastics with reinforcements embedded in the wall comprising one or more layers of a helically wound cord or wire three or more layers

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Mechanical Engineering (AREA)
  • Soil Sciences (AREA)
  • Water Supply & Treatment (AREA)
  • Environmental Sciences (AREA)
  • Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)

Abstract

PURPOSE: A polishing method of metal materials is provided to give superior physical properties to metal materials without discharging environmental pollutants. CONSTITUTION: The method comprises steps of (i) degrease step in which after processing a metal material such as S45C, the metal material is dipped in a solution comprising NONOH, Na2CO3, NaO2 at about 80deg.C for 30min; (ii) pre heat treatment in which the metal material degreased is heated at 300deg.C for 30min; (iii) post heat treatment in which the metal material is re-dipped in above solution at about 575deg.C for 0.5-1hr; (iv) first cooling in which the metal material heat-treated is dipped in a cooling solution comprising NaCNO, KCl, Na2CO3 at 330 to 400deg.C for 10-15min; (v) polishing operation; (vi) second cooling in which metal material polished is re-dipped in the abovementioned cooling solution at 330-400deg.C for 10-15min; (vii) washing operation in which the metal material cooled is washed as cooling the cooling solution from 200 to 100deg.C; (viii) drying operation in which metal material is wind-dried after taken out from the cooling solution.

Description

금속재의 열처리방법{Heat-processing method of metal materials}Heat-processing method of metal materials

본 발명은 산업전반의 각종 샤프트(Shaft) 및 유공압실린더, 선박용자재, 금형 코아(Core) 및 부품, 공작계 및 자동차 부품등에 사용되는 금속재료의 열처리 및 연마 방법에 관한 것으로, 특히, 재료를 공업용나트륨, 탄산소다 및 아초산을 주성분으로 하는 화학제에 함침시켜 가열후, 이를 청산소다, 연화가리, 탄산소다등을 주성분으로 한 냉각제에 냉각하고, 폴리싱등의 연마공정을 거친 후, 다시 냉각제에 냉각시켜 가공하므로서 재료의 내식성, 내열성, 내마모성 및 내피로성을 향상시키고 재료비와 가공비를 최소화하여 경제적으로도 큰기여를 할 수 있는 금속재의 열처리방법에 관한 것이다.BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for heat treatment and polishing of metal materials used in various shafts and pneumatic cylinders, marine materials, mold cores and parts, work systems, and automobile parts in general. After impregnating with chemicals containing sodium, sodium carbonate, and acetic acid as main components, heating them, cooling them with a cooling agent mainly composed of sodium cyanide, softened lead, sodium carbonate, etc. The present invention relates to a heat treatment method of a metal material which can contribute economically by improving the corrosion resistance, heat resistance, abrasion resistance and fatigue resistance of materials and minimizing material cost and processing cost by cooling and processing.

종래의 각종 각종 샤프트(Shaft) 및 유공압실린더, 선박용자재, 금형 코아(Core) 및 부품, 공작계 및 자동차 부품등에 사용되는 금속재료를 열처리하기 위하여는 탄소강(S45C)등의 재료를 쓰고저하는 형상과 모양으로 가공한 후 이를 고온으로 열처리하여 물이나 공기중에서 냉각시키므로서 그 강도와 경도를 향상시키거나, 반대로 열처리된 재료를 원하는 형상 및 모양으로 가공하여 사용해 왔다.In order to heat-treat metal materials used in various conventional shafts and hydraulic cylinders, marine materials, mold cores and parts, machine tools and automotive parts, materials such as carbon steel (S45C) are used. After processing to a shape and heat treatment at high temperature to cool in water or air to improve the strength and hardness, or conversely, the heat-treated material has been used to process the desired shape and shape.

또한, 상기와 같이 가공이 완료된 금속재의 미감을 향상시켜 제품의 가치를 극대화 하고저 표면에 크롬등으로 도색을 하여 왔다.In addition, by improving the aesthetics of the finished metal material as described above to maximize the value of the product has been painted with chromium on the surface.

그러나 상기와 같은 방법의 금속재의 가공방법 중 가공후 열처리방법은 열처리에 의해 일정한 모양으로 가공된 금속재가 냉각중 병형이 될 수 있어 극히 정확한 정밀도를 요하는 부품으로 사용시 어려움이 있으며, 열처리 후 가공방법은 재료가 열처리 되어 그 강도와 경도가 극대화 되어 있는 상태에서 가공을 해야하므로 가공이 매우 어려운 문제점이 있었다.However, the heat treatment method after processing of the metal material processing method of the above method is difficult to use as a component requiring extremely accurate precision because the metal material processed to a certain shape by heat treatment can become a bottle shape during cooling, processing method after heat treatment Silver material is heat-treated, so the strength and hardness must be processed in a state that maximizes the processing was very difficult problem.

또한, 상기와 같은 방법으로 가공된 금속재료는 경도와 강도는 어느정도 충족해 주지만 그 부품이 쓰여지는 곳의 내식성이나 내열성, 내마모성을 모두 동시에 만족시켜주지는 못하므로 제품의 선정 및 사용에 큰 어려움이 있으며, 크롬등으로 표면을 처리하므로서 그 화학물질이 인체에 미치는 악영향과 환경오염의 우려로 최근들어 각종 국제기구나 환경단체에 의해 그 사용을 금지시키는 움직임이 활발해지고 있어 대체물질의 개발이 시급한 실정이다.In addition, the metal material processed by the above method satisfies the hardness and the strength to some extent, but it does not satisfy the corrosion resistance, heat resistance, and abrasion resistance at the same time where the parts are used, so it is difficult to select and use the product. In addition, due to the toxic effects on the human body and the environmental pollution by treating the surface with chromium, etc., the movement of prohibiting its use by various international organizations and environmental organizations has been active in recent years. to be.

본 발명은 상기와 같은 문제점을 해결하기 위하여 안출된 것으로서, 재료를 공업용나트륨, 탄산소다 및 아초산을 주성분으로 하는 화학제에 함침시켜 가열후, 이를 청산소다, 연화가리, 탄산소다등을 주성분으로 한 냉각제에 냉각하고, 폴리싱등의 연마공정을 거친 후, 다시 냉각제에 냉각시켜 가공하므로서 재료의 내식성, 내열성, 내마모성 및 내피로성을 향상시키고, 재료비와 가공비를 최소화하여 경제적으로도 큰기여를 할 수 있도록 함은 물론 크롬과 같은 인체 및 환경유해 물질의 대체물질로 사용이 가능한 금속재의 열처리방법을 제공함에 본 발명의 목적이 있다.The present invention has been made in order to solve the above problems, the material is impregnated with a chemical agent mainly composed of industrial sodium, sodium carbonate and acetic acid, and after heating, it is dissolved in cyanide, softened, soda carbonate as a main component After cooling with one coolant, polishing and polishing process, and then cooling with coolant, processing can improve the corrosion resistance, heat resistance, abrasion resistance and fatigue resistance of materials, and minimize the material cost and processing cost, which can contribute economically. It is an object of the present invention to provide a heat treatment method of a metal material that can be used as a substitute material of human and environmentally harmful substances such as chromium.

이하, 본 발명의 바람직한 실시예를 살펴본다.Below, it looks at a preferred embodiment of the present invention.

우선, 본 발명공정을 살펴보면 다음과 같다.First, the process of the present invention is as follows.

탄소강(S45C)등과 같은 금속재를 일정한 형상으로 가공후, 이를 공업용나트륨(NONOH), 탄산소타(NA2CO3), 아초산(NAO2)으로 조성된 혼합물에 침지시켜 약 80℃의 온도로 약 30분간 가열하여 불순물을 제거하는 탈지공정과;After processing a metal material such as carbon steel (S45C) into a certain shape, it is immersed in a mixture composed of industrial sodium (NONOH), sodium carbonate (NA 2 CO 3 ), acetic acid (NAO 2 ) to a temperature of about 80 ℃ A degreasing step of removing impurities by heating for 30 minutes;

공기중에서 300℃의 온도로 약 30분간 가열하는 예열공정과;A preheating step of heating the air at a temperature of 300 ° C. for about 30 minutes;

이를 다시 혼합물에 침지시켜 약 575℃의 온도로 30분~1시간동안 가열하는 본열공정과;Dipping it again in a mixture and heating it at a temperature of about 575 ° C. for 30 minutes to 1 hour;

가열된 재료를 청산소다(NACNO), 염화가리(KCL), 탄산소타(NA2CO3)로 조성된 냉각제에 침지시켜 330℃~400℃의 온도로 10~15분간 냉각시키는 1차 냉각공정과;A primary cooling process in which the heated material is immersed in a coolant composed of sodium cyanide (NACNO), chlorine chloride (KCL), and sodium carbonate (NA 2 CO 3 ) and cooled at a temperature of 330 ° C to 400 ° C for 10 to 15 minutes; ;

폴리싱, 보러싱, 바렐, 호닝, 버핑 등으로 연마하는 연마공정과;A polishing step of polishing by polishing, boring, barrel, honing, buffing, or the like;

이를 다시 전기한 냉각제에 침지시켜 330℃~400℃의 온도로 10~15분간 냉각시키는 2차 냉각공정과;A second cooling step of immersing it in the aforementioned coolant and cooling it for 10 to 15 minutes at a temperature of 330 ° C to 400 ° C;

냉각제를 200℃에서 100℃로 순차적으로 냉각시키면서 재료를 세척하는 세척공정과;A washing step of washing the material while sequentially cooling the coolant from 200 ° C to 100 ° C;

재료를 냉각제로부터 꺼내어 공기중에서 송풍건조하는 건조공정으로 이루어지는 것이다.It is made of the drying process which removes a material from a coolant, and blow-drys in air.

상기와 같은 각 공정의 작용을 살펴본다.Look at the operation of each process as described above.

우성 본 발명의 탈지공정과 예열공정, 본열공정에서 사용되어지는 혼합물은 공업용나트륨(NONOH), 탄산소타(NA2CO3), 아초산(NAO2)으로 조성되어 있어 재료가 이 혼합물에 의해 상기 공정들을 거치게 되면 재료의 표면과 혼합물 사이에 탄산염(CO3)을 생성시키고, 복원중에 탄산염(CO3)은 CNO로 되어 감소하는 것이다.The mixture used in the degreasing process, preheating process, and preheating process of the present invention is composed of industrial sodium (NONOH), sodium carbonate (NA 2 CO 3 ), and acetic acid (NAO 2 ). The process produces carbonate (CO 3 ) between the surface of the material and the mixture, and during recovery the carbonate (CO 3 ) is reduced to CNO.

또한, 표면에 Fe3N, Fe4N의 두가지 화합물을 형성하여 미끄럼성, 내열성, 내마모성을 향상시키는 것이다.In addition, by forming two compounds of Fe 3 N, Fe 4 N on the surface to improve the slip resistance, heat resistance, wear resistance.

한편, 1,2차 냉각 공정에 사용되어 지는 냉각제는 청산소다(NACNO), 염화가리(KCL), 탄산소타(NA2CO3)로 조성되어 이에 재료를 침지시켜 330℃~400℃의 온도로 10~15분 냉각시키면 CN, CNO가 완전히 파괴되는 것이다.Meanwhile, the coolant used in the 1st and 2nd cooling process is composed of sodium cyanide (NACNO), chlorinated chloride (KCL) and sodium carbonate (NA 2 CO 3 ), and the material is immersed in it to a temperature of 330 ° C to 400 ° C. After 10 to 15 minutes of cooling, CN and CNO are completely destroyed.

특히 1차 냉각공정후에 이루어지는 폴리싱(Polishing) 공정으로 금속표면의이물질을 제거하고 연마한 후, 다시 2차 냉각공정을 제처리 수행하므로서 내식성을 향상 시키는 것이다.In particular, the polishing (polishing) process after the first cooling process removes and polishes the foreign material on the metal surface, and then the second cooling process is reprocessed to improve the corrosion resistance.

즉, 표면에 Fe3O4의 철산화물층을 형성하는 것이다.That is, the iron oxide layer of Fe 3 O 4 is formed on the surface.

이와 같이 1차 냉각, 폴리싱, 2차냉각 공정을 마친 후에는 고온에서 저온으로 온도의 변화를 주면서 재료를 냉각시키므로서 재료의 변형을 최소화 하는 것이다.As such, after the first cooling, polishing, and second cooling processes are completed, the deformation of the material is minimized by cooling the material while changing the temperature from a high temperature to a low temperature.

또한, 상기와 같은 본 발명의 공정으로 SUS재질을 처리하게 되면, 표면을 검은색으로 도색하는 것과 같은 효과를 볼 수 있어 별도의 크롬도금 등의 공정이 필요없어 작업자 및 사용자의 안전은 물론, 환경오염을 방지할 수 있고, 내식성, 내마모성, 표면저항, 칫수안정성이 아래의 표1에서 나타난 것과 같이 종래의 경질크롬도금, 무전해니켈도금, 티탄코팅 보다 우수한 것이다.In addition, when the SUS material is processed by the process of the present invention as described above, it is possible to obtain the same effect as painting the surface in black, and there is no need for a separate chromium plating process, so that the safety of workers and users as well as the environment Contamination can be prevented, and corrosion resistance, abrasion resistance, surface resistance, and dimensional stability are superior to conventional hard chromium plating, electroless nickel plating, and titanium coating as shown in Table 1 below.

본 발명과 종래 제품의 비교분석표Comparative analysis table of the present invention and conventional products 구 분division 본 발명The present invention 경질크롬도금Hard chrome plating 무전해 니켈도금Electroless Nickel Plating 티탄코팅Titanium coating 내식성(염수TEST)Corrosion Resistance (Brine TEST) 220HR양호220HR 70시간70 hours 100시간100 hours 74시간74 hours 내마모성Wear resistance HV1200HV1200 HV900HV900 HV600~700HV600 ~ 700 슬라이딩(표면저항)Sliding (Surface Resistance) 가장우수Best 우수하나마모Excellent wear 우수Great 우수Great 칫수안정성Dimensional stability 가장우수(0.002)Best (0.002) 미흡(0.02)Poor (0.02) 우수Great 미흡Inadequate

이상과 같이 본 발명은 산업전반의 각종 샤프트(Shaft) 및 유공압실린더, 선박용자재, 금형 코아(Core) 및 부품, 공작계 및 자동차 부품등에 사용되는 금속재료를 공업용나트륨, 탄산소다 및 아초산을 주성분으로 하는 화학제에 함침시켜 가열후, 이를 청산소다, 연화가리, 탄산소다등을 주성분으로 한 냉각제에 냉각하고, 폴리싱등의 연마공정을 거친 후, 다시 냉각제에 냉각시켜 가공하므로서 재료의 내식성, 내열성, 내마모성 및 내피로성을 향상시키고 재료비와 가공비를 최소화하여 경제적으로도 큰 기여를 할 수 있게 한 것이다.As described above, the present invention mainly comprises industrial sodium, sodium carbonate, and acetic acid as metal materials used in various shafts and pneumatic cylinders, marine materials, mold cores and parts, work systems, and automotive parts. After impregnating with chemicals and heating, it is cooled in a coolant mainly composed of sodium cyanide, softened briquettes, and soda carbonate. In addition, it has made economic contributions by improving wear resistance and fatigue resistance and minimizing material and processing costs.

상기와 같이 본 발명은 재료를 공업용나트륨, 탄산소다 및 아초산을 주성분으로 하는 화학제에 함침시켜 가열후, 이를 청산소다, 연화가리, 탄산소다등을 주성분으로 한 냉각제에 1차 냉각하고, 폴리싱등의 연마공정을 거친 후, 다시 2차 냉각제에 냉각시켜 가공하므로서 재료의 내식성, 내열성, 내마모성 및 내피로성을 향상시키고, 재료비와 가공비를 최소화하여 경제적으로도 큰기여를 할 수 있도록 함은 물론 크롬과 같은 인체 및 환경유해 물질의 대체물질로 사용이 가능한 것이다.As described above, the present invention is impregnated with a chemical agent mainly composed of industrial sodium, sodium carbonate, and acetic acid, and then heated, and then first cooled in a coolant mainly composed of sodium cyanide, softened briquettes, sodium carbonate, and the like. After the grinding process, such as by cooling with a secondary coolant to further improve the corrosion resistance, heat resistance, abrasion resistance and fatigue resistance of the material, and to minimize the material cost and processing cost to contribute to economical contributions, as well as chrome It can be used as a substitute for human and environmentally harmful substances.

Claims (1)

탄소강(S45C)등과 같은 금속재를 일정한 형상으로 가공후, 이를 공업용나트륨(NONOH), 탄산소타(NA2CO3), 아초산(NAO2)으로 조성된 혼합물에 침지시켜 약 80℃의 온도로 약 30분간 가열하여 불순물을 제거하는 탈지공정과;After processing a metal material such as carbon steel (S45C) into a certain shape, it is immersed in a mixture composed of industrial sodium (NONOH), sodium carbonate (NA 2 CO 3 ), acetic acid (NAO 2 ) to a temperature of about 80 ℃ A degreasing step of removing impurities by heating for 30 minutes; 공기중에서 300℃의 온도로 약 30분간 가열하는 예열공정과;A preheating step of heating the air at a temperature of 300 ° C. for about 30 minutes; 이를 다시 혼합물에 침지시켜 약 575℃의 온도로 30분~1시간동안 가열하는 본열공정과;Dipping it again in a mixture and heating it at a temperature of about 575 ° C. for 30 minutes to 1 hour; 가열된 재료를 청산소다(NACNO), 염화가리(KCL), 탄산소타(NA2CO3)로 조성된 냉각제에 침지시켜 330℃~400℃의 온도로 10~15분간 냉각시키는 1차 냉각공정과;A primary cooling process in which the heated material is immersed in a coolant composed of sodium cyanide (NACNO), chlorine chloride (KCL), and sodium carbonate (NA 2 CO 3 ) and cooled at a temperature of 330 ° C to 400 ° C for 10 to 15 minutes; ; 폴리싱, 보러싱, 바렐, 호닝, 버핑 등으로 연마하는 연마공정과;A polishing step of polishing by polishing, boring, barrel, honing, buffing, or the like; 이를 다시 전기한 냉각제에 침지시켜 330℃~400℃의 온도로 10~15분간 냉각시키는 2차 냉각공정과;A second cooling step of immersing it in the aforementioned coolant and cooling it for 10 to 15 minutes at a temperature of 330 ° C to 400 ° C; 냉각제를 200℃에서 100℃로 순차적으로 냉각시키면서 재료를 세척하는 세척공정과;A washing step of washing the material while sequentially cooling the coolant from 200 ° C to 100 ° C; 재료를 냉각제로부터 꺼내어 공기중에서 송풍건조하는 건조공정으로 이루어짐을 특징으로 하는 금속재의 열처리방법.A heat treatment method of a metal material, characterized in that it comprises a drying step of removing the material from the coolant and air-dried in the air.
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