KR940006036B1 - Coated steel sheets with a wear resistance - Google Patents
Coated steel sheets with a wear resistance Download PDFInfo
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- KR940006036B1 KR940006036B1 KR1019920009872A KR920009872A KR940006036B1 KR 940006036 B1 KR940006036 B1 KR 940006036B1 KR 1019920009872 A KR1019920009872 A KR 1019920009872A KR 920009872 A KR920009872 A KR 920009872A KR 940006036 B1 KR940006036 B1 KR 940006036B1
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
- C23C4/04—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the coating material
- C23C4/06—Metallic material
- C23C4/067—Metallic material containing free particles of non-metal elements, e.g. carbon, silicon, boron, phosphorus or arsenic
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C37/00—Cast-iron alloys
- C22C37/06—Cast-iron alloys containing chromium
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C4/00—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge
- C23C4/12—Coating by spraying the coating material in the molten state, e.g. by flame, plasma or electric discharge characterised by the method of spraying
- C23C4/123—Spraying molten metal
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Abstract
Description
제1도는 본발명의 제조공정도.1 is a manufacturing process diagram of the present invention.
제2도는 본발명의 제조장치 개략도.2 is a schematic view of the manufacturing apparatus of the present invention.
제3 (a)도는 제2도의 A-A선 단면도, 제3(b)도는 제2도의 B-B선 단면도.FIG. 3 (a) is a cross-sectional view taken along the line A-A of FIG. 2, and FIG. 3 (b) is a cross-sectional view taken along the line B-B of FIG.
본발명은 고경도 피복층을 갖는 피복강판에 관한것으로, 보다 상세하게는 고탄소-크롬계 합금주철을 금속재 표면에 융착시킴에 따라 내마모성, 내열성, 내소착성을 갖도록함과 함께 저렴한 단가를 갖는데 적합한 피복강판에 관한 것이다.The present invention relates to a coated steel sheet having a high hardness coating layer, and more particularly, it is suitable to have a low unit cost as well as wear resistance, heat resistance, and adhesion resistance by fusing high carbon-chromium alloy cast iron to the metal surface. It relates to a coated steel sheet.
내열성, 내마모성, 내부식성을 요하는 각종 산업분야(광산, 시멘트공장, 제철 및 화학공장, 원자력 및 화학발전소 등 각종 산업설비)에 이용되는 금속재료는 용도에 따라 여러가지가 있으나, 일반적으로 소재 전체를 고합금강재질로 하는 경우는 성능은 우수한데 반해 고가 금속성분이 전체를 이루고 있어 가격이 비싸다.Metal materials used in various industrial fields (mining, cement plants, steel and chemical plants, nuclear and chemical power plants, etc.) that require heat resistance, abrasion resistance, and corrosion resistance vary depending on the purpose. In the case of high alloy steel materials, the performance is excellent, but the expensive metal components make up the whole.
또한, 내마모성과 내소착성을 요하는 용도에 있어서는 A형 흑면으로서 내소착성을 향상시킴과 함께 탄화물을 분산시켜 내마모성을 부여한 특수 합금주철이 사용되고 있다.In addition, in applications requiring wear resistance and adhesion resistance, a special alloy cast iron is used as an A-type black surface which improves wear resistance and disperses carbides to impart wear resistance.
그러나 이는 강도적인 측면에 문제가 있어 두께를 크게하여야 함으로 그 두께가 두꺼우며 열응력이 증대됨과 함께 경량화를 가할수 없다.However, this has a problem in terms of strength, so the thickness must be increased, the thickness is thick, thermal stress is increased, and weight cannot be applied.
따라서, 최근에는 강도를 갖는 일반 강종(또는 저합금강)을 소재로하고 그 표면에 합금원소를 용사피복시켜 사용하고 있다.Therefore, in recent years, general steel grades (or low alloyed steels) having strength have been used as materials and alloy elements are thermally coated on their surfaces.
이때 피복방법으로서는 소재 전체를 연속 이동가열 시키면서 그 표면에 고합금강을 용사시켜 소재와 합금원소 사이에 확산층을 형성시키면서 서냉 또는 급냉처리하여 밀착성이 양호한 복합층을 갖게하고 있다.At this time, as the coating method, the whole material is continuously heated and thermally sprayed with high alloy steel on the surface thereof to form a diffusion layer between the material and the alloying element while slow cooling or quenching to provide a composite layer having good adhesion.
그 일예로서 일본 공개 특허공보 소 63-114954호와 같이 소재(모재) 표면에 고 Ni-Cr강을 용사피복하고 있는데 이때 피복재료는 선철중의 탄소(C)를 비롯한 불순물을 일단 제거하는 제강 공정을 거쳐야 함은 물론 이때 사용되는 원소는 고가인 Ni, Co, W, Ti등의 사용량이 많아 제조원가의 상승 요인이 되는등 제거공정에 따른 제조공정이 복잡하다.As an example, as in Japanese Laid-Open Patent Publication No. 63-114954, high Ni-Cr steel is thermally coated on the surface of the material (base material). At this time, the coating material is a steelmaking process that removes impurities such as carbon (C) in pig iron. Of course, the elements used at this time are expensive, such as the use of expensive Ni, Co, W, Ti, etc., the manufacturing cost is complicated by the removal process, such as an increase in the manufacturing cost.
뿐만아니라 기타 선행기술에서도 고가의 합금강들이 일반적으로 사용되고 있다. 이에 본발명은 상기한 종래의 문제점을 개선하기위해 안출한 것으로, 고탄소-크롬계 합금주철을 소재(모재) 표면에 피복시킴에 따라 저렴한 제조단가를 비롯한 우수한 내마모성과 내열성을 갖는 표면 피복 강판을 제공하고자 하는데 그 목적이 있다. 이하, 본 발명을 설명한다.In addition, expensive alloy steels are generally used in other prior art. Accordingly, the present invention has been made to improve the above-described problems, and by coating a high-carbon-chromium alloy cast iron on the surface of the material (base material), a surface-coated steel sheet having excellent wear resistance and heat resistance, including low manufacturing cost, The purpose is to provide. Hereinafter, the present invention will be described.
본 발명은 금속소재 표면에 중량%로서 C : 4.5-5.5%, Mn : 0.2%이하, Si : 0.5-1.5%, Cr : 20-25%, Mo : 3.0-7.0%, V : 0.4-1.5%, W : 0.5-2.5%, Nb : 3.0-7.0%이고 나머지는 Fe로 이루어진 조성물을 피복한다.In the present invention, C: 4.5-5.5%, Mn: 0.2% or less, Si: 0.5-1.5%, Cr: 20-25%, Mo: 3.0-7.0%, V: 0.4-1.5% , W: 0.5-2.5%, Nb: 3.0-7.0% and the rest covers the composition consisting of Fe.
이와같은 본발명에서 금속소재는 강인성을 갖는, 일반강종, 저합금강, 스테인레스 강등 강종재질이 사용되는 한편 피복층은 내마모성, 내소착성, 내열성이 우수한 상기의 고판소-크롬계 조성물로 이루어진 것으로서, 상기 피복조성물을 금속 소재에 용착시킴에 따라 피복층과 소재의 중간 사이의 계면층에서 상호 확산이 이루어져 밀착된 접촉으로 일체화되며, 다음에서 설명되는 화학 조성에따라 내마모성, 내열성, 내소착성을 갖는 성질을 갖게된다.In the present invention, the metal material has a toughness, general steel grade, low alloy steel, stainless steel and other steel grade materials are used, while the coating layer is composed of the high plate-chromium-based composition excellent in wear resistance, adhesion resistance, and heat resistance. As the coating composition is welded to a metal material, the interfacial diffusion between the coating layer and the middle part of the material is carried out to be integrated into a close contact, and according to the chemical composition described below, it has properties of wear resistance, heat resistance, and adhesion resistance. Will have
이하 화학성분(중량% 표시)의 수치한정에 대해 설명한다.The numerical limitation of chemical components (% by weight) is described below.
C(탄소) : 4.5-5.5중량%,C (carbon): 4.5-5.5% by weight,
탄소는 흑연과 하기에서 설명하는 탄화물을 형성시키므로서 내소착성과 내마모성을 증대 시킨다. 따라서 4.0%이하면 효과가 적고 6.0%이상이면 카바이드가 조대화하여 취화를 이르킨다.Carbon forms graphite and the carbides described below, thereby increasing adhesion and wear resistance. Therefore, less than 4.0% is less effective, if more than 6.0% carbides coarse leads to embrittlement.
Mn(망간) : 0.2중량%이하,Mn (manganese): 0.2 wt% or less,
Mn은 S를 제거하여 기지를 강화시킨다.Mn removes S and strengthens the matrix.
Si(규소) : 0.5-1.5중량%,Si (silicon): 0.5-1.5% by weight,
규소는 내산화성을 향상시키는 효과를 나타냄과 함께 흑연화 촉진 원소로서, 흑연량과 탄화물량의 비율을 결정한다. 따라서, 0.5%미만에서는 흑연량이 부족하여 내소착성이 열화되고, 너무 지나치면 카바이드가 조대화하여 취화를 이르킨다. 가장 바람직하기로는 0.8-1.2%이다.Silicon exhibits an effect of improving oxidation resistance and determines the ratio of graphite amount to carbide amount as a graphitization promoting element. Therefore, if it is less than 0.5%, the amount of graphite is insufficient and the ignition resistance deteriorates. If too much, the carbide coarsens and leads to embrittlement. Most preferably 0.8-1.2%.
Cr(크롬) : 20-25중량%,Cr (chromium): 20-25% by weight,
크롬은 Mo, Mi과 같이 기지에 강인성을 부여하는 역활도 하지만, 고경도의 탄화물생성이 강하다. 따라서 본발명에서는 고가의 Mi, Co, Ti, Zr, Ta, B를 사용하지 않는 대신 사용량을 증대시켜(Fe Cr)7C3형태의 복합탄화물을 형성시켜 하기에서 언급되는 NbC탄화물 다음으로 경하다. 가장바람직하기로는 22-23%Chromium has the role of giving toughness to the base like Mo and Mi, but it has strong hard carbide production. Therefore, in the present invention, instead of using expensive Mi, Co, Ti, Zr, Ta, and B, the amount of use is increased (Fe Cr) to form a composite carbide of 7 C 3 type, followed by N b C carbide mentioned below. Light Most preferably 22-23%
Mo(몰리브덴) : 3.0-7.0중량%,Mo (molybdenum): 3.0-7.0% by weight,
Cr과 유사하나 고온 강도를 향상시킴과 함께 Fe-Mo복탄화물을 형성하여 내마모성을 향상시킨다.It is similar to Cr but improves high temperature strength and forms Fe-Mo complex carbide to improve wear resistance.
따라서 그 사용량이 적으면 결정립 크기나 내마모성이 저하되면, 너무 많으면 취약하여 가공성이 저하된다. 가장 바람직하기로는 4-6%이다.Therefore, when the amount is small, the grain size and the wear resistance decrease, and when the amount is too high, the fragility decreases and the workability decreases. Most preferably 4-6%.
V(비나듬) : 0.4-1.5중량%,V (non-fracture): 0.4-1.5% by weight,
V는 결정립을 미세화하여 기지의 인성 강도를 증대시킴과 함께 강력한 탄화물을 형성하므로 소량의 첨가로서도 내열, 내마모성을 향상시킨다. 따라서 그량의 적으면 효과가 적고 너무 많으면 기계 가공성이 경제적으로 불리하다. 가장 바람직하기로는 0.5-1.0%이다.V refines the grains to increase the toughness of the matrix and to form strong carbides, thereby improving heat resistance and abrasion resistance even with a small amount. Therefore, if the amount is small, the effect is small, and if too large, the machinability is economically disadvantageous. Most preferably 0.5-1.0%.
W(텅스텐) : 0.5-2.5%,W (tungsten): 0.5-2.5%,
탄화물을 형성하여 내열 및 내마모성을 증대시키며 고온 강도를 갖게한다.Carbide is formed to increase heat and wear resistance and to have high temperature strength.
이런 효과는 Cr, Mo, V와 복합 첨가할 경우 특히 현저하다.This effect is especially noticeable when combined with Cr, Mo, V.
0.5%미만이면 효과가 적고, 2.5%초과하여도 증진된 효과를 기대할수 없으며 오히려 인성을 저하 시킨다.If it is less than 0.5%, the effect is small, and if it exceeds 2.5%, the enhanced effect cannot be expected, but rather, the toughness is lowered.
Nb(니오비움) : 3.0-7.0%Nb (niobium): 3.0-7.0%
Nb는, C, N, O와 친화력이 강하여 탄질화물을 형성시킨다.Nb has strong affinity with C, N, O, and forms carbonitride.
일반적으로는 결정립계에 석출하는 N 및 O를 고정하여 탄화물 또는 질화물 형태로서 결정립계를 비롯한 결정립내에도 균일하게 분포석출하여 충격치를 비롯한 내마모성을 증대시킨다. 가장바람직하기로는 4-6중량%이다.In general, N and O precipitated at grain boundaries are fixed to uniformly distribute precipitates in grains including carbide grains as carbide or nitride forms to increase wear resistance including impact values. Most preferably, it is 4-6% by weight.
다음은 제1도 및 제2도에 따라 구체적으로 설명한다.The following will be described in detail with reference to FIGS. 1 and 2.
제1도는 본 발명의 제조공정도로서, 상기한 피복조성비가 되게끔 조성물을 정산, 배합하여 고주파 진공용해로에서 용해시키고 피복할 소재(모재)를 불활성 가스 분위기에서 약 900℃예열하면서 용해로 하측 노즐에 연속이동시켜 소재기판상에 용해금속을 용사하여 피착 시킨다.FIG. 1 is a manufacturing process diagram of the present invention, in which the composition is settled and blended so as to achieve the above-described coating composition ratio, and dissolved in a high frequency vacuum melting furnace. By spraying molten metal on the substrate.
이와같은 용착도중 소재 기판은 고온으로 예열되어있기 때문에 용해금속이 소재와 접하게 되면 피착될 용해금속과 소재계면에서 상호 확산 반응이 일어나 양호한 접착이 이루어진다.During the welding, the substrate is preheated to a high temperature, and thus, when the molten metal comes into contact with the material, a good diffusion occurs between the molten metal to be deposited and the material interface.
이런 용착 공정후 후판일경우나 재경화 처리 및 내부응력 제거가 필요한 경우는 900-1050℃로 승온하여 열처리한다.In the case of thick plate after such welding process, or when re-curing treatment and internal stress removal is necessary, heat it by heating up to 900-1050 ℃.
제2도는 본발명에 이용되는 제조장치의 개략도이고, 제3(a)도와 제3(b)도는 제2도의 A-A선 및 B-B선 단면도이다. 이에 나타난 바와같이 피복한 혼합조성물을 원료탱크(1)에서 진공고주파 용해로(2)에 장입하여 본발명의 조성비 범위로 용해 시키고, 용해로 하측에는 세라믹 지지판(3)을 연속이동시키는 이송로울러(4)를 설치하고, 이지지판(3)위에 소재(5)를 올려 놓는다.2 is a schematic diagram of a manufacturing apparatus used in the present invention, and FIGS. 3A and 3B are cross-sectional views taken along lines A-A and B-B of FIG. As shown in the figure, the coated composite composition is charged from the raw material tank 1 into the vacuum high frequency melting furnace 2 to dissolve in the composition ratio of the present invention, and the transfer roller 4 continuously moves the ceramic support plate 3 below the melting furnace. Install it, put the material (5) on the support plate (3).
그리고 용해로 좌측에는 소재를 예열하는 예열실(6)을 구비하고 용해로 우측에는 피복후 냉각처리하는 냉각실(7)을 구비한다.A preheating chamber 6 for preheating the raw material is provided on the left side of the melting furnace, and a cooling chamber 7 for cooling after coating is provided on the right side of the melting furnace.
이와같은 구조에 따라, 소재가 연속이동하면서 예열실(6)에서 900℃정도로 예열되고 용해로 하측 노즐로부터 용탕이 소재표면에 용사되어 일정두께로 피착층(8)이 형성된다.According to this structure, the material is continuously moved, preheated to about 900 ° C. in the preheating chamber 6, and the molten metal is sprayed on the surface of the material from the lower nozzle of the melting furnace to form the adhered layer 8 at a predetermined thickness.
그리고 피착 완료후 N2가스 분위기를 갖는 냉각실(7)에서 제3(b)도와 같이 냉각수(9)를 분사시켜 냉각처리 하게된다.After the deposition is completed, the cooling water 9 is sprayed and cooled in the cooling chamber 7 having the N 2 gas atmosphere as shown in FIG. 3 (b).
이와같은 장치에서는 예열실로부터 냉각이 완료될때까지는 챔버내를 불활성 가스 분위기로하여 처리한다.In such an apparatus, the chamber is treated with an inert gas atmosphere until cooling is completed from the preheating chamber.
[표 1]은 본발명의 각종 조성물의 조성비를 나타낸 것이고 [표 2]는 [표 1]의 시료에 따른 경도시험을 한결과이다.Table 1 shows the composition ratios of various compositions of the present invention, and Table 2 shows the results of hardness tests according to the samples in Table 1.
[표 1]TABLE 1
[표 2]TABLE 2
참고 : 평균계산시 최고치와 최소치는 제외함.Note: When calculating the average, the maximum and minimum values are excluded.
HRc : 록크웰경도(ROCKWELL HARDNESS)HRc: Rockwell Hardness
HV : 마이크로 피커스 경도(MICRO VICKERS HARDNESS)HV: MICRO VICKERS HARDNESS
C : 카바이트(CARBIDE)C: CARBIDE
M : 기지(MATRIX)M: Base (MATRIX)
이상에서와 같이 종래의 경우는 소재 전체를 제강공정을 통한 고가의 금속 원료를 사용하거나 또한 일반 강종 표면에 고합금강을 융착하므로서 제조단가가 높은데 반해, 본 발명은 고탄소-크롬합금철을 금속 표면에 피착하므로서 내마모성, 내열성, 내소착성을 갖게함과 동시에 저렴한 피복강판을 제공할수 있어 각종 산업 분야의 설비재료로 널리 이용될 수 있다.As described above, in the conventional case, the manufacturing cost is high by using an expensive metal raw material through the steelmaking process as a whole or by fusion of high alloy steel on the surface of a general steel grade, whereas the present invention provides a high carbon-chromium alloy metal surface. It can be widely used as equipment material in various industrial fields because it can provide abrasion resistance, heat resistance, adhesion resistance and at the same time can provide an inexpensive coated steel sheet.
Claims (2)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1019920009872A KR940006036B1 (en) | 1992-06-08 | 1992-06-08 | Coated steel sheets with a wear resistance |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1019920009872A KR940006036B1 (en) | 1992-06-08 | 1992-06-08 | Coated steel sheets with a wear resistance |
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| Publication Number | Publication Date |
|---|---|
| KR940000597A KR940000597A (en) | 1994-01-03 |
| KR940006036B1 true KR940006036B1 (en) | 1994-07-02 |
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| KR100617210B1 (en) * | 1999-08-12 | 2006-08-31 | 엘지전자 주식회사 | method for administration of graphic memory |
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