KR20130000727A - Spheroidal graphite cast iron and method for producing the same - Google Patents
Spheroidal graphite cast iron and method for producing the same Download PDFInfo
- Publication number
- KR20130000727A KR20130000727A KR1020110061431A KR20110061431A KR20130000727A KR 20130000727 A KR20130000727 A KR 20130000727A KR 1020110061431 A KR1020110061431 A KR 1020110061431A KR 20110061431 A KR20110061431 A KR 20110061431A KR 20130000727 A KR20130000727 A KR 20130000727A
- Authority
- KR
- South Korea
- Prior art keywords
- cast iron
- graphite
- strength
- nodular
- iron
- 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.)
- Ceased
Links
- 229910001141 Ductile iron Inorganic materials 0.000 title claims abstract description 24
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 22
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 28
- 229910052802 copper Inorganic materials 0.000 claims abstract description 5
- 229910052748 manganese Inorganic materials 0.000 claims abstract description 5
- 229910052759 nickel Inorganic materials 0.000 claims abstract description 5
- 229910052720 vanadium Inorganic materials 0.000 claims abstract description 5
- 239000012535 impurity Substances 0.000 claims abstract description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 31
- 229910002804 graphite Inorganic materials 0.000 claims description 29
- 239000010439 graphite Substances 0.000 claims description 29
- 238000000034 method Methods 0.000 claims description 19
- 229910001018 Cast iron Inorganic materials 0.000 claims description 14
- 238000001816 cooling Methods 0.000 claims description 12
- 229910001562 pearlite Inorganic materials 0.000 claims description 12
- 229910052742 iron Inorganic materials 0.000 claims description 11
- 238000005266 casting Methods 0.000 claims description 7
- 239000000463 material Substances 0.000 claims description 5
- 229910052751 metal Inorganic materials 0.000 claims description 5
- 239000002184 metal Substances 0.000 claims description 5
- 239000000203 mixture Substances 0.000 claims description 4
- 238000002844 melting Methods 0.000 claims description 3
- 230000008018 melting Effects 0.000 claims description 3
- 229910000859 α-Fe Inorganic materials 0.000 claims description 3
- 239000012768 molten material Substances 0.000 claims description 2
- 238000010438 heat treatment Methods 0.000 description 6
- 230000015572 biosynthetic process Effects 0.000 description 4
- 230000002787 reinforcement Effects 0.000 description 4
- 238000007711 solidification Methods 0.000 description 4
- 230000008023 solidification Effects 0.000 description 4
- 238000002347 injection Methods 0.000 description 3
- 239000007924 injection Substances 0.000 description 3
- 238000010309 melting process Methods 0.000 description 3
- 230000000704 physical effect Effects 0.000 description 3
- INZDTEICWPZYJM-UHFFFAOYSA-N 1-(chloromethyl)-4-[4-(chloromethyl)phenyl]benzene Chemical compound C1=CC(CCl)=CC=C1C1=CC=C(CCl)C=C1 INZDTEICWPZYJM-UHFFFAOYSA-N 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 239000000969 carrier Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 238000005204 segregation Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 206010000117 Abnormal behaviour Diseases 0.000 description 1
- 229910000990 Ni alloy Inorganic materials 0.000 description 1
- 229910000805 Pig iron Inorganic materials 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 238000005275 alloying Methods 0.000 description 1
- 229910001563 bainite Inorganic materials 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- 238000011033 desalting Methods 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 239000005431 greenhouse gas Substances 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
- LEONUFNNVUYDNQ-UHFFFAOYSA-N vanadium atom Chemical compound [V] LEONUFNNVUYDNQ-UHFFFAOYSA-N 0.000 description 1
- 238000010792 warming Methods 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/04—Making ferrous alloys by melting
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/08—Making cast-iron alloys
- C22C33/10—Making cast-iron alloys including procedures for adding magnesium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C37/00—Cast-iron alloys
- C22C37/04—Cast-iron alloys containing spheroidal graphite
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C37/00—Cast-iron alloys
- C22C37/10—Cast-iron alloys containing aluminium or silicon
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C2202/00—Physical properties
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
Abstract
Fe를 주성분으로 하고, C: 3.0~4.0 wt%, Si: 2.5~3.2 wt%, Mn: 0.2~0.6 wt%, P: 0.01~0.05 wt%, S: 0.01~0.05 wt%, Mg: 0.015~0.045 wt%, Cu: 0.3~0.7 wt%, Ni: 0.1~0.9 wt%, V: 0.01~0.8 wt% 및 불가결한 불순물을 포함하는 성분으로 구성된 고강도 구상흑연주철 및 그 제조방법이 소개된다.With Fe as the main component, C: 3.0 to 4.0 wt%, Si: 2.5 to 3.2 wt%, Mn: 0.2 to 0.6 wt%, P: 0.01 to 0.05 wt%, S: 0.01 to 0.05 wt%, Mg: 0.015 to A high-strength nodular cast iron composed of a component containing 0.045 wt%, Cu: 0.3-0.7 wt%, Ni: 0.1-0.9 wt%, V: 0.01-0.8 wt% and indispensable impurities and a method of manufacturing the same are introduced.
Description
본 발명은 구상흑연주철을 고강도화 함으로써 샤시부품의 강성을 확보하여 하중증가에 따른 설계보강으로 부품 중량이 증가하는 것을 막을 수 있는 고강도 구상흑연주철 및 그 제조방법에 관한 것이다.The present invention relates to a high-strength nodular cast iron and a method for manufacturing the same, which ensures the rigidity of the chassis parts by increasing the strength of the nodular graphite cast iron, thereby preventing the component weight from increasing due to the design reinforcement according to the load increase.
구상흑연주철은 자동차 주행 중 타이어를 통해 들어오는 하중을 지지하여 타이어의 이상거동을 방지하고 서스펜션의 위치를 결정하는 기능을 하는 너클/캐리어 같은 샤시부품에 많이 사용되고 있다.Spheroidal graphite cast iron is widely used in chassis parts such as knuckles / carriers that support the load coming from the tires while driving the vehicle to prevent abnormal behavior of the tires and determine the position of the suspension.
최근에는 편의사양 등의 추가로 인해 차량의 중량이 증가함에 따라 샤시부품이 받는 하중은 더욱 증가할 수밖에 없는 실정이다. Recently, as the weight of the vehicle increases due to the addition of convenience specifications, the load on the chassis parts is inevitably increased.
한편, 전 세계적으로 지구온난화의 방지를 위해, 온실가스의 배출량을 감축하기 위고 자동차의 연비 향상을 요구하고 있으며, 이에 따라 자동차 부품의 경량화 필요성이 크게 부각되고 있는 추세이다.On the other hand, in order to prevent global warming around the world, in order to reduce the emission of greenhouse gases, and to improve the fuel efficiency of the automobile, there is a trend that the need for lighter weight of automobile parts is increasing.
따라서 그러한 추세에서 샤시부품 역시 경량화의 필요가 요구되고 있는데, 구상흑연주철은 근본적으로 철과 흑연의 복합체로서 그 성질은 흑연량, 흑연크기, 흑연형상 및 기지조직에 좌우된다. Therefore, in such a trend, chassis parts are also required to be lightweight. Spheroidal graphite cast iron is essentially a composite of iron and graphite, and its properties depend on the amount of graphite, the size of the graphite, the shape of the graphite, and the matrix structure.
따라서 적당한 합금원소를 첨가하여 기지조직의 강화와 동시에 흑연의 석출량, 형상, 크기 및 분포상태를 개량하여 기계적 성질을 개선시키고 있다. 구상흑연주철은 보통 400~800 MPa의 인장강도 특성을 가지고 있으며, 연신율은 20~2%로 강도에 반비례하는 관계를 나타내고 있다. Therefore, by adding a suitable alloying element to strengthen the matrix structure and improve the mechanical properties by improving the amount, shape, size and distribution of graphite. Spheroidal graphite cast iron has a tensile strength characteristic of 400 ~ 800 MPa, and the elongation is inversely proportional to the strength of 20 ~ 2%.
현재까지의 구상흑연주철은 강도를 높임에 따른 신율의 저하로 인하여 불가피하게 450~600 MPa, 15~7% 수준의 기계적 물성을 가질 수 있도록 제작하여 사용하고 있다.
To date, nodular cast iron has been manufactured and used inevitably to have mechanical properties of 450 to 600 MPa and 15 to 7% due to the decrease in elongation at high strength.
도 1은 종래의 구상흑연주철의 제조공정을 나타낸 도면이고, 도 2는 도 1의 제조공정에 따른 열처리 조건을 나타낸 도면이다. 1 is a view showing a conventional manufacturing process of spherical graphite iron, Figure 2 is a view showing the heat treatment conditions according to the manufacturing process of FIG.
종래의 기술은 기존의 구상흑연주철에 0.1~0.3 wt%의 Mo , 0.1~3.0 wt%의 Ni 합금을 첨가하고 850~950℃의 온도로 가열한 후 300~400℃의 염욕에서 유지하는 오스템퍼링 열처리를 통하여 강도와 인성을 향상시키는 방안을 사용하였다. The prior art is to add a 0.1 ~ 0.3 wt% of Mo, 0.1-3.0 wt% Ni alloy to the existing spheroidal graphite cast iron, and to maintain at a salt bath of 300-400 ℃ after heating to a temperature of 850 ~ 950 ℃ The method of improving strength and toughness through heat treatment was used.
이를 통해 900~1100 MPa의 인장강도에 12~5%의 연신율을 갖는 기계적 물성을 확보하였으나, 높은 경도로 인해 절삭공구수명이 감소하고 가공속도가 낮아져 가공비용이 상승하는 단점으로 인해 널리 실용화되지 못하고 있다.
This secured mechanical properties with an elongation of 12 to 5% at a tensile strength of 900 to 1100 MPa.However, due to the high hardness, the cutting tool life is reduced and the machining speed is lowered. have.
따라서, 본 발명은 구상흑연주철을 고강도화함으로써 샤시부품의 강성을 확보하여, 하중증가에 따른 설계보강으로 부품 중량이 증가하는 것을 막고자 하는데 그 목적이 있다.Accordingly, an object of the present invention is to prevent rigidity of the chassis parts by increasing the strength of the spherical graphite cast iron, thereby preventing the weight of the parts from increasing by design reinforcement according to the increase in load.
상기의 배경기술로서 설명된 사항들은 본 발명의 배경에 대한 이해 증진을 위한 것일 뿐, 이 기술분야에서 통상의 지식을 가진자에게 이미 알려진 종래기술에 해당함을 인정하는 것으로 받아들여져서는 안 될 것이다.The matters described as the background art are only for the purpose of improving the understanding of the background of the present invention, and should not be taken as acknowledging that they correspond to the related art already known to those skilled in the art.
본 발명은 이러한 문제점을 해결하기 위하여 제안된 것으로, 구상흑연주철을 고강도화함으로써 샤시부품의 강성을 확보하여, 하중증가에 따른 설계보강으로 부품 중량이 증가하는 것을 막고자 하며, 동시에 강도가 증대되더라도 가공에 필요한 연신율을 확보하는데 그 목적이 있다.The present invention has been proposed to solve this problem, to secure the stiffness of the chassis parts by increasing the strength of the nodular cast iron, to prevent the parts weight increases by design reinforcement according to the increase of load, and at the same time processing even if the strength is increased The purpose is to secure the elongation required for
상기의 목적을 달성하기 위한 본 발명에 따른 고강도 구상흑연주철은, Fe를 주성분으로 하고, C: 3.0~4.0 wt%, Si: 2.5~3.2 wt%, Mn: 0.2~0.6 wt%, P: 0.01~0.05 wt%, S: 0.01~0.05 wt%, Mg: 0.015~0.045 wt%, Cu: 0.3~0.7 wt%, Ni: 0.1~0.9 wt%, V: 0.01~0.8 wt% 및 불가결한 불순물을 포함한다.The high-strength nodular cast iron according to the present invention for achieving the above object has Fe as a main component, C: 3.0 to 4.0 wt%, Si: 2.5 to 3.2 wt%, Mn: 0.2 to 0.6 wt%, P: 0.01 ~ 0.05 wt%, S: 0.01-0.05 wt%, Mg: 0.015-0.045 wt%, Cu: 0.3-0.7 wt%, Ni: 0.1-0.9 wt%, V: 0.01-0.8 wt% and indispensable impurities do.
상기 구상흑연주철의 흑연 형상은 80% 이상 구상화되고 크기는 평균 60㎛ 이하일 수 있다.The graphite shape of the nodular graphite iron may be spheroidized by 80% or more and the average size may be 60 μm or less.
상기 구상흑연주철의 미세조직은 펄라이트가 70~90%, 페라이트가 10~30%로 구성될 수 있다.The microstructure of the nodular cast iron may be composed of pearlite 70 ~ 90%, ferrite 10 ~ 30%.
한편, 상기 고강도 구상흑연주철의 제조방법은, 청구항 1 조성의 재료를 용해하여 용탕을 제조하는 용해과정; 상기 용해된 재료를 1300~1500℃에서 주형에 주입하는 주입과정; 상기 주물을 응고하되 냉각속도를 조절하여 펄라이트의 함량이 70~90%가 되도록 하는 응고과정; 및 상기 주물을 탈형시키고 공랭하는 공랭과정;을 포함한다.On the other hand, the high-strength nodular cast iron manufacturing method, the melting process of melting the material of the composition of claim 1 to produce a molten metal; Injecting the dissolved material into the mold at 1300 to 1500 ° C; Solidifying the casting, but controlling the cooling rate so that the content of pearlite becomes 70 to 90%; And an air cooling process for demolding and casting the casting.
상술한 바와 같은 구조로 이루어진 고강도 구상흑연주철 및 그 제조방법에 따르면, 구상흑연주철을 고강도화함으로써 샤시부품의 강성을 확보하여, 하중증가에 따른 설계보강으로 부품 중량이 증가하는 것을 막을 수 있으며, 동시에 강도가 증대되더라도 가공에 필요한 연신율을 확보할 수 있게 된다.According to the high-strength nodular cast iron and the manufacturing method of the structure as described above, by increasing the strength of the nodular graphite cast iron to secure the rigidity of the chassis parts, it is possible to prevent the weight of the parts to increase due to the design reinforcement according to the load increase, Even if the strength is increased, it is possible to secure the elongation required for processing.
도 1은 종래의 구상흑연주철의 제조공정을 나타낸 도면.
도 2는 도 1의 제조공정에 따른 열처리 조건을 나타낸 도면.
도 3은 본 발명의 일 실시예에 따른 구상흑연주철의 제조공정을 나타낸 도면.
도 4는 본 발명의 일 실시예에 따른 구상흑연주철의 물성을 나타낸 표.1 is a view showing a manufacturing process of a conventional nodular cast iron.
2 is a view showing a heat treatment condition according to the manufacturing process of FIG.
3 is a view showing a manufacturing process of spherical graphite iron according to an embodiment of the present invention.
Figure 4 is a table showing the physical properties of the nodular graphite iron in accordance with an embodiment of the present invention.
이하에서는 첨부된 도면을 참조하여 본 발명의 바람직한 실시 예에 따른 고강도 구상흑연주철 및 그 제조방법에 대하여 살펴본다.Hereinafter, with reference to the accompanying drawings looks at with respect to high-strength nodular cast iron and a manufacturing method according to a preferred embodiment of the present invention.
본 발명의 일 실시예에 따른 고강도 구상흑연주철은 Fe를 주성분으로 하고, C: 3.0~4.0 wt%, Si: 2.5~3.2 wt%, Mn: 0.2~0.6 wt%, P: 0.01~0.05 wt%, S: 0.01~0.05 wt%, Mg: 0.015~0.045 wt%, Cu: 0.3~0.7 wt%, Ni: 0.1~0.9 wt%, V: 0.01~0.8 wt% 및 불가결한 불순물을 포함하는 성분으로 구성될 수 있다.The high-strength nodular cast iron according to the embodiment of the present invention has Fe as a main component, C: 3.0 to 4.0 wt%, Si: 2.5 to 3.2 wt%, Mn: 0.2 to 0.6 wt%, P: 0.01 to 0.05 wt% , S: 0.01-0.05 wt%, Mg: 0.015-0.045 wt%, Cu: 0.3-0.7 wt%, Ni: 0.1-0.9 wt%, V: 0.01-0.8 wt%, and components containing indispensable impurities Can be.
C의 경우 3.0~4.0 wt%를 포함함이 바람직한데, 이는 탄소 증가를 통해 인장강도를 증가시키기 위함이고, 탄소가 4% 이상이면 연신율 저하가 일어나기 때문이다.In the case of C, it is preferable to include 3.0 to 4.0 wt%, because it is to increase the tensile strength through the increase of carbon, because the elongation is lowered if the carbon is 4% or more.
또한, Si의 경우 2.5~3.2 wt%가 바람직한데, 이는 Si가 2.5 이상일 경우 흑연형성을 촉진하고 베이나이트 탄화물의 형성을 억제하기 대문이다. 그러나 Si가 3.2 이상이면 편석을 증가시키기 때문에 제한함이 바람직하다.In addition, in the case of Si, 2.5 to 3.2 wt% is preferable, because it promotes graphite formation and suppresses the formation of bainite carbide when Si is 2.5 or more. However, since Si increases segregation when Si is 3.2 or more, it is preferable to limit.
Mn의 경우 0.2~0.6 wt%가 바람직한데, 이는 0.2 이상의 경우 펄라이트를 안정화시키기 때문이다. 다만, 0.6 이상일 경우에는 응고도중 편석에 의한 탄화물 형성으로 인성이 저하되기 때문에 제한함이 바람직하다.In the case of Mn, 0.2 to 0.6 wt% is preferable because it stabilizes pearlite when 0.2 or more. However, in the case of 0.6 or more, it is preferable to limit the toughness due to carbide formation due to segregation during solidification.
한편, P는 0.01~0.05 wt%가 바람직하고, S는 0.01~0.05 wt%가 바람직하며, Mg는 0.015~0.045 wt%가 바람직하다. Mg는 흑연형상을 구상화하는 것으로서 역할한다.On the other hand, P is preferably 0.01 to 0.05 wt%, S is preferably 0.01 to 0.05 wt%, and Mg is preferably 0.015 to 0.045 wt%. Mg serves as spheroidizing the graphite shape.
그리고, Cu는 0.3~0.7 wt%가 바람직한데, 0.3 이상시 경화능이 향상되나 0.7 이상시 그 효과 미미하므로 제한함이 바람직하다.And, Cu is preferably 0.3 ~ 0.7 wt%, the hardenability is improved at 0.3 or more, but when the 0.7 or more the effect is insignificant, it is preferable to limit.
또한, Ni은 0.1~0.9 wt%가 바람직한데, 0.1 이상시 펄라이트의 촉진제로서 작용하고 고온에서의 물성향상에 도움을 주나, 0.9 이상시에는 소재의 원가상승측면이 강하기 때문에 제한함이 바람직하다.In addition, Ni is preferably in the range of 0.1 to 0.9 wt%, which acts as an accelerator of pearlite at 0.1 or more and helps to improve physical properties at high temperatures.
마지막으로 V의 경우 0.01~0.8 wt%가 바람직한데, 바나듐(V)은 펄라이트 조직 생성을 촉진하며, 미세한 바나듐 탄화물(VC)을 석출시킴으로써 조직을 강화시키는 역할을 한다. 또한 흑연 형상 및 크기를 균일하게 만들어 준다. 0.01 이상시에는 펄라이트 생성을 촉진하나, 0.8 이상시에는 탄화물 성장에 의해 인성이 저하되므로 제한함이 바람직하다.
Lastly, in the case of V, 0.01 to 0.8 wt% is preferred. Vanadium (V) promotes the formation of pearlite tissue and serves to strengthen the tissue by depositing fine vanadium carbide (VC). It also makes the graphite shape and size uniform. When it is 0.01 or more, pearlite is promoted, but when it is 0.8 or more, toughness is reduced by carbide growth.
한편, 상기와 같은 조성으로 형성된 구상흑연주철은 흑연 형상의 80% 이상이 구상화되고 그 크기는 평균 60㎛ 이하로 될 수 있다. 또한, 상기 구상흑연주철의 미세조직은 펄라이트가 70~90%, 페라이트가 10~30%로 구성될 수 있다.On the other hand, the spherical graphite cast iron formed by the composition as described above may be spheroidized more than 80% of the graphite shape and the size may be 60㎛ or less on average. In addition, the microstructure of the nodular cast iron may be composed of pearlite is 70 ~ 90%, ferrite 10 ~ 30%.
그러한 성상을 통하여 본 발명의 구상흑연주철은 도 4의 물성치를 확보할 수 있어 적절한 강도와 연성을 확보할 수 있는 것이다. 또한 소재 자체도 경량화가 추구될 수 있다.Through such properties, the nodular cast iron of the present invention can secure the physical properties shown in FIG. 4 to ensure proper strength and ductility. In addition, the material itself can be pursued to be lightweight.
본 발명이 적용가능한 아이템으로는 너클, 캐리어, 암류, 브라켓류 등의 샤시부품을 들 수 있고, 구상흑연주철은 강도증대시 신율이 저하되어 일반적인 샤시부품으로는 부적합하고, 기존의 고강도 주철은 강도와 신율을 만족하나, 가공성이 저하되어 양산성이 부족한바, 본 발명의 구상흑연주철은 이러한 종래 주철의 단점을 커버할 수 있게 된다.
Examples of items to which the present invention is applicable include chassis parts such as knuckles, carriers, arms, and brackets. Spheroidal graphite cast iron is unsuitable for general chassis parts due to a decrease in elongation at the time of increasing strength. And satisfies the elongation, but the workability is deteriorated due to the lack of mass production, the nodular graphite cast iron of the present invention can cover the disadvantages of such conventional cast iron.
도 3은 본 발명의 일 실시예에 따른 구상흑연주철의 제조공정을 나타낸 도면으로서, 본 발명의 구상흑연주철의 제조공정은, 청구항 1 조성의 재료를 용해하여 용탕을 제조하는 용해과정(S100); 상기 용해된 재료를 1300~1500℃에서 주형에 주입하는 주입과정(S200); 상기 주물을 응고하되 냉각속도를 조절하여 펄라이트의 함량이 70~90%가 되도록 하는 응고과정(S300); 및 상기 주물을 탈형시키고 공랭하는 공랭과정(S400);을 포함한다.Figure 3 is a view showing a manufacturing process of the nodular graphite iron according to an embodiment of the present invention, the manufacturing process of the nodular graphite iron of the present invention, the melting process of melting the material of the composition of claim 1 to produce a molten metal (S100) ; Injecting the molten material into the mold at 1300 to 1500 ° C. (S200); Solidifying the casting, but controlling the cooling rate so that the content of pearlite becomes 70 to 90% (S300); It includes; and the air cooling process (S400) for demolding the casting and air cooling.
이러한 제조공정은 소재를 상기 Fe를 주성분으로 하고, C: 3.0~4.0 wt%, Si: 2.5~3.2 wt%, Mn: 0.2~0.6 wt%, P: 0.01~0.05 wt%, S: 0.01~0.05 wt%, Mg: 0.015~0.045 wt%, Cu: 0.3~0.7 wt%, Ni: 0.1~0.9 wt%, V: 0.01~0.8 wt% 및 불가결한 불순물을 포함하는 성분으로 구성함으로써 불필요한 열처리 공정을 생략할 수 있어 도 1의 종래 공정에 비해 제조원가가 현저히 낮아지게 된다.This manufacturing process is based on Fe as the main component, C: 3.0 to 4.0 wt%, Si: 2.5 to 3.2 wt%, Mn: 0.2 to 0.6 wt%, P: 0.01 to 0.05 wt%, S: 0.01 to 0.05 WT%, Mg: 0.015 to 0.045 wt%, Cu: 0.3 to 0.7 wt%, Ni: 0.1 to 0.9 wt%, V: 0.01 to 0.8 wt% and unnecessary components by eliminating unnecessary heat treatment As a result, the manufacturing cost is significantly lower than that of the conventional process of FIG. 1.
용해과정에서는 상기 조성의 선철을 용해하여 용탕을 제조한다. 그리고 주입과정에서는 1300~1500℃ 온도에서 수분내 주입을 실시하도록 한다. 그 후 응고과정에서는 펄라이트의 함량이 70~90% 생성되도록 냉각속도를 조절하여 응고하고, 공냉과정에서는 탈사 후 공냉하여 적재토록 한다.In the melting process, the molten pig iron is dissolved to prepare a molten metal. And in the injection process to perform the injection in water at a temperature of 1300 ~ 1500 ℃. Thereafter, in the solidification process, the cooling rate is solidified to produce 70 to 90% of the pearlite content.
또는, 선철을 용해하여 용탕을 제조한 후 1300~1500℃ 온도에서 수분내 주입하고, 용탕 주입 전에 소량의 Mg 첨가로 흑연형상을 편상에서 구상으로 바꾸고 구상화율은 80%이상 유지한다. 또한 냉각 속도를 조절하여 응고 과정에서 미세조직의 펄라이트 함량이 70~90% 생성되도록 하고, 탈사 후 공냉하여 적재하는 것도 가능하다.
Alternatively, molten iron may be melted to prepare a molten metal, and then injected into the water at a temperature of 1300 to 1500 ° C, and a small amount of Mg may be added before the molten iron is injected to change the graphite shape from flake to spherical shape and maintain the nodularity at least 80%. In addition, by adjusting the cooling rate, the pearlite content of the microstructure is produced 70-90% during the solidification process, it is also possible to load by air cooling after desalting.
이러한 본 발명의 고강도 구상흑연주철 및 그 제조방법에 따르면, 500 MPa급 구상주철 대비 30% 이상 인장강도를 향상시키고, 연신율은 10% 대로 유사한 수준의 구상흑연주철을 얻을 수 있다. According to the high-strength nodular cast iron and the manufacturing method of the present invention, it is possible to improve the tensile strength of more than 30% compared to the 500 MPa-grade nodular cast iron, the elongation of 10% can obtain a similar level of nodular cast iron.
한편, 기존 구상주철은 700 MPa 수준의 인장강도에서는 2% 정도의 신율을 나타나므로 인성을 요구하는 샤시부품에 부적합하였다. 따라서 종래 고강도 구상주철에서는 열처리 공정을 추가함으로써 우수한 기계적 물성을 확보하였지만, 본 발명에서는 합금성분 및 미세조직 제어로 강도를 향상시킬 수 있게 되었다.On the other hand, the existing spheroidal cast iron showed an elongation of about 2% at a tensile strength of 700 MPa, which is not suitable for chassis parts requiring toughness. Therefore, in the conventional high-strength spheroidal cast iron, excellent mechanical properties have been secured by adding a heat treatment process, but in the present invention, the strength of the alloy component and the microstructure can be improved.
그리고, 종래 고강도 구상주철 대비 제조공정이 단순하고 제조원가가 저렴하며, 가공성이 우수하여 가공시간 및 툴비용이 적게 든다. 또한, 종래 기술 대비 공정 및 원가 측면에서 양산성이 훨씬 우수하고, 추가 설비 및 공정이 필요없고 생산싸이클타임도 적어서 대량생산에 유리하다.In addition, compared to the conventional high strength spheroidal cast iron, the manufacturing process is simple, the manufacturing cost is low, and the workability is excellent, the processing time and the tool cost are low. In addition, it is much more mass-produced in terms of process and cost compared to the prior art, it is advantageous for mass production because no additional equipment and processes are required and production cycle time is small.
한편, 본 기술을 통하여 기존 구상주철 부품을 고강도 구상주철로 변경하게 되면, 원가는 동등 수준이면서도 10%의 중량절감 효과가 있으며, 실시 예로 기존 너클(4.5kg/개)에 본 발명의 고강도 구상흑연주철을 적용하게 되면 고강도 너클(4.0kg/개)로 동등수준의 성능을 발휘하며 대당 1.0kg의 중량절감 효과가 있게 된다.
On the other hand, when changing the existing spheroidal cast iron parts to high-strength spheroidal iron through the present technology, the cost is equivalent to the weight saving effect of 10%, for example, the high-strength spheroidal graphite of the present invention to the existing knuckle (4.5kg / piece) When cast iron is applied, high-strength knuckles (4.0kg / piece) are equivalent in performance and weight savings of 1.0kg per unit.
본 발명은 특정한 실시예에 관련하여 도시하고 설명하였지만, 이하의 특허청구범위에 의해 제공되는 본 발명의 기술적 사상을 벗어나지 않는 한도 내에서, 본 발명이 다양하게 개량 및 변화될 수 있다는 것은 당 업계에서 통상의 지식을 가진 자에게 있어서 자명할 것이다.
While the present invention has been particularly shown and described with reference to specific embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the following claims It will be apparent to those of ordinary skill in the art.
S100 : 용해과정 S200 : 주입과정
S300 : 응고과정 S400 : 공랭과정S100: Dissolution Process S200: Injection Process
S300: solidification process S400: air cooling process
Claims (4)
상기 구상흑연주철의 흑연 형상은 80% 이상 구상화되고 크기는 평균 60㎛ 이하인 것을 특징으로 하는 고강도 구상흑연주철.The method according to claim 1,
The graphite shape of the nodular graphite cast iron is spherical graphite 80% or more and the size of the high-strength nodular graphite iron, characterized in that less than 60㎛.
상기 구상흑연주철의 미세조직은 펄라이트가 70~90%, 페라이트가 10~30%로 구성된 것을 특징으로 하는 고강도 구상흑연주철.The method according to claim 1,
The microstructure of the nodular graphite cast iron is high strength nodular graphite cast iron, characterized in that consisting of pearlite 70 ~ 90%, ferrite 10 ~ 30%.
상기 용해된 재료를 1300~1500℃에서 주형에 주입하는 주입과정(S200);
상기 주물을 응고하되 냉각속도를 조절하여 펄라이트의 함량이 70~90%가 되도록 하는 응고과정(S300); 및
상기 주물을 탈형시키고 공랭하는 공랭과정(S400);을 포함하는 고강도 구상흑연주철의 제조방법.Dissolving process (S100) of producing a molten metal by melting the material of the composition;
Injecting the molten material into the mold at 1300 to 1500 ° C. (S200);
Solidifying the casting, but controlling the cooling rate so that the content of pearlite becomes 70 to 90% (S300); And
A method for producing high-strength nodular cast iron comprising: an air cooling process (S400) for demolding the casting and air cooling.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1020110061431A KR20130000727A (en) | 2011-06-24 | 2011-06-24 | Spheroidal graphite cast iron and method for producing the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1020110061431A KR20130000727A (en) | 2011-06-24 | 2011-06-24 | Spheroidal graphite cast iron and method for producing the same |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| KR20130000727A true KR20130000727A (en) | 2013-01-03 |
Family
ID=47834131
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| KR1020110061431A Ceased KR20130000727A (en) | 2011-06-24 | 2011-06-24 | Spheroidal graphite cast iron and method for producing the same |
Country Status (1)
| Country | Link |
|---|---|
| KR (1) | KR20130000727A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108642368A (en) * | 2018-04-27 | 2018-10-12 | 武汉理工大学 | A kind of As-cast High Strength Toughness synthetic nodular cast iron QT800-5 and preparation method thereof |
-
2011
- 2011-06-24 KR KR1020110061431A patent/KR20130000727A/en not_active Ceased
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108642368A (en) * | 2018-04-27 | 2018-10-12 | 武汉理工大学 | A kind of As-cast High Strength Toughness synthetic nodular cast iron QT800-5 and preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101660097B (en) | Wear-resisting alloy steel with high boron, high chrome and low carbon and preparation method thereof | |
| KR101957274B1 (en) | Spheroidal graphite cast iron having exceptional strength and ductility and method for manufacturing same | |
| CN103201399B (en) | High-carbon-chromium bearing steel and preparation method thereof | |
| CN105220060B (en) | High-strength ductile iron and production method thereof | |
| JP2003533593A (en) | Iron-based alloy containing chromium-tungsten composite carbide and method for producing the same | |
| KR20160025518A (en) | Spheroidal graphite cast iron | |
| KR102542938B1 (en) | High strength grey cast iron | |
| CN106216405A (en) | It is applicable to nitridation high speed steel rider and the manufacture method thereof of bar cutting frame | |
| CN102317480B (en) | Method to obtain a high resistance gray iron alloy for combustion engines and general casts | |
| KR20130087213A (en) | High strength flake graphite iron using rare earth element and preparation method thereof | |
| KR20220054862A (en) | Alloy structural steel and its manufacturing method | |
| JP5282546B2 (en) | High-strength, thick-walled spheroidal graphite cast iron with excellent wear resistance | |
| CN104532107A (en) | Vanadium-titanium vermicular cast iron brake drum and manufacture method thereof | |
| JP3723706B2 (en) | High-strength spheroidal graphite cast iron and method for producing the same | |
| JP6358975B2 (en) | Flake graphite cast iron and method for producing the same | |
| KR20130000727A (en) | Spheroidal graphite cast iron and method for producing the same | |
| JP4527304B2 (en) | High strength high toughness spheroidal graphite cast iron | |
| JP2007197747A (en) | Cast iron containing spheroidal graphite | |
| JP2013079418A (en) | Thin-walled spheroidal graphite cast iron casting | |
| JP4565301B2 (en) | High-strength spheroidal graphite cast iron and method for producing the same | |
| KR101042480B1 (en) | Manufacturing method of casting roll | |
| JP4963444B2 (en) | Spheroidal graphite cast iron member | |
| WO2000075387A1 (en) | Non-austempered spheroidal graphite cast iron | |
| JP2006175494A (en) | Method for producing ferritic casting of ductile cast iron | |
| KR100708958B1 (en) | Vehicle knuckles and manufacturing method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A201 | Request for examination | ||
| PA0109 | Patent application |
Patent event code: PA01091R01D Comment text: Patent Application Patent event date: 20110624 |
|
| PA0201 | Request for examination | ||
| PG1501 | Laying open of application | ||
| PE0902 | Notice of grounds for rejection |
Comment text: Notification of reason for refusal Patent event date: 20130305 Patent event code: PE09021S01D |
|
| E601 | Decision to refuse application | ||
| PE0601 | Decision on rejection of patent |
Patent event date: 20130603 Comment text: Decision to Refuse Application Patent event code: PE06012S01D Patent event date: 20130305 Comment text: Notification of reason for refusal Patent event code: PE06011S01I |