EP0695811A1 - High heat-resisting iron-base alloy - Google Patents

High heat-resisting iron-base alloy Download PDF

Info

Publication number
EP0695811A1
EP0695811A1 EP95305233A EP95305233A EP0695811A1 EP 0695811 A1 EP0695811 A1 EP 0695811A1 EP 95305233 A EP95305233 A EP 95305233A EP 95305233 A EP95305233 A EP 95305233A EP 0695811 A1 EP0695811 A1 EP 0695811A1
Authority
EP
European Patent Office
Prior art keywords
base alloy
bal
high heat
resisting iron
alloy according
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.)
Withdrawn
Application number
EP95305233A
Other languages
German (de)
French (fr)
Inventor
Hiroyuki Shamoto
Takashi Morikawa
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Toyota Motor Corp
Original Assignee
Toyota Motor Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Toyota Motor Corp filed Critical Toyota Motor Corp
Publication of EP0695811A1 publication Critical patent/EP0695811A1/en
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • 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

Definitions

  • the present invention relates to an Fe-Al-C-base alloy and more particularly to an iron-base alloy, having excellent heat resistance, for use at high temperatures.
  • Such high heat resisting iron-base materials known in the art include, for example, SCH-base heat resisting steel casting materials (JIS G5122) and FCDA-base nodular graphite austenitic iron castings (JIS G5510).
  • high-silicon nodular graphite cast iron can be first mentioned.
  • Cr incorporated in an amount of not less than 15% in this material, however, is expensive.
  • austenitic cast iron can also be mentioned as a material for use at high temperatures. In this material as well, Cr or Ni, which is an expensive alloying element, is used.
  • Japanese Unexamined Patent Publication (Kokai) No. 3-226547 which has been filed by the applicant of the present invention, discloses, as a high toughness material, an Fe-Al-base intermetallic compound material having an Al content of 36.8 to 49.4 at.%. As with the conventional heat resisting materials, this intermetallic compound material contains Cr from the viewpoint of improving the toughness.
  • Japanese Unexamined Patent Publication (Kokai) No. 56-58950 discloses an alloy, having an Al content of 0.72 to 18.7 at.%, for a heat treatment roll having an improved pickup property.
  • Japanese Unexamined Patent Publication (Kokai) No. 57-126949 discloses an alloy, having an Al content of 17 to 32.7 at.%, as a vibration control alloy which causes regular-irregular transformation.
  • Japanese Unexamined Patent Publication (Kokai) No. 62-270452 discloses an alloy, having an Al content of 13.5 to 37.3 at.% and a C content of 0.004 to 3.2 at.%, for a carbon fiber-reinforced concrete structure with a reinforcing bar being embedded therein, and Japanese Unexamined Patent Publication (Kokai) No.
  • 6-25800 discloses an alloy, having an Al content of 25 to 50 at.%, for a high-strength and abrasion-resisting material with a carbide being dispersed therein. None of the above known techniques, however, disclose an Fe-Al-C ternary alloy as at least heat resisting material.
  • Al cast iron it is known that, by virtue of a strong Al2O3 film formed by Al incorporated on the surface of the Al cast iron, the Al cast iron does not permit the penetration of oxygen thereinto, has excellent oxidation resistance at a high temperature, is less likely to cause growth of a carbide, and has excellent heat resistance (see, for example, "Tokushu Chutetsu (Special Cast Iron),” 3rd edition, published by Nikkan Kogyo Shimbun, Ltd., 1960).
  • An object of the present invention is to study an Fe-Al-C-base alloy as a ternary alloy with a view to solving the above problems of an Fe-Al-base alloy and to provide a high heat-resisting iron-base alloy having lowered average coefficient of linear expansion, enhanced transformation temperature, and excellent tensile strength.
  • Another object of the present invention is to provide a high heat-resisting iron-base alloy mainly consisting of Fe, Al, and C alone without use of conventional expensive alloying elements, such as Cr and Ni, which high heat-resisting iron-base alloy is inexpensive and has improved mechanical properties equal or superior to the conventional alloys.
  • a further object of the present invention is to provide a high heat-resisting iron-base alloy through study of ingredients capable of reducing the problem associated with the production of an Fe-Al-base alloy, particularly improving the castability.
  • Fig. 1 is a diagram showing the scope of the first invention in terms of the relationship between the C content and the Al content.
  • Fig. 2 is a diagram showing the scope of the second invention in terms of the relationship between the C content and the Al content.
  • Fig. 3 is a diagram showing the scope of the third invention in terms of the relationship between the C content and the Al content.
  • Fig. 4 is a diagram showing the scope of the fourth invention in terms of the relationship between the C + 0.75Si amount and the Al content.
  • Figs. 5(a) to 5(c) are metallic structure photographs of Fe-10 at.% Al-2 at.% C alloy showing the effect of the refining element according to thirteenth and fourteenth claims, Fig. 5(a) shows without addition, Fig. 5(b) shows with addition of 0.8 at.% TiB2, Fig. 5(c) shows with addition of 1.9 at.% TiB2.
  • the alloy of the first invention has a low coefficient of thermal expansion and creates neither significant strain nor significant stress even under high temperature environments and, hence, can be an excellent heat resisting material.
  • the alloy of the second invention has a high transformation temperature and creates neither significant expansion nor significant shrinkage even under high temperature conditions and, hence, can be an excellent heat resisting material.
  • the alloy of the third invention has a low coefficient of thermal expansion and, in addition, high tensile strength and, hence, can be an excellent heat resisting material.
  • the oxidation resistance becomes unsatisfactory, while when it exceeds 28 at.%, the coefficient of thermal expansion becomes large, making it difficult to use the alloy as a heat resisting material.
  • the C content exceeds 24 at.%, the melting point of the alloy is high, making it very difficult to melt the alloy.
  • the lower limit of the C content is more than 0 at.% exclusive of the value on the line C: of 0 at.% in Fig. 1.
  • Points E, F, G, H, and I in Fig. 2 are each a boundary point where two regions cross. 5y - 8z ⁇ 25 (here, z ⁇ 5 at.%) 5y - 2z ⁇ 55 (5 at.% ⁇ z ⁇ 10 at.%) y ⁇ 15 (10 at.% ⁇ z ⁇ 15 at.%) y + 3z ⁇ 60 (15 at.% ⁇ z) wherein y and z represent a value of Al at.% and a value of C at.%, respectively, and the formulae in parentheses represent applicable content regions in respective inequalities.
  • the lower limit of the C content is more than 0 at.% exclusive of the value on the line C: of 0 at.% in Fig. 2.
  • the transformation temperature of the material is 800°C or above, indicating that the material can be used as a heat resisting material at a temperature up to 800°C or above and, hence, is suitable for use in high temperature environments of exhaust systems and other systems of vehicles.
  • the alloy of the third invention should satisfy the requirement specified in the first invention and a requirement represented by the following formula, that is, has a composition falling within the range shown in Fig. 3. C ⁇ 12 at.%
  • This limitation is provided because when the C content exceeds 12 at.%, the tensile strength cannot be provided, rendering the strength of the alloy unsatisfactory.
  • Fe-Al-Si alloy falls within the area formed by connecting points A, J, L, M, B, C and D shown in Fig. 4 and satisfies the formulas hereunder.
  • z total C + 0.75Si 0.2 at.% ⁇ Si ⁇ 10 at.%
  • the compositions of Al, C and Si are in the range of satisfying the above three conditions.
  • Si effects changing the transformation temperature, with the result that the heat resistance can be improved by rising the limited temperature of the heat resistance application. More, Si improves the resistance to oxidation, with the result that the heat resistance of the material can be improved.
  • mechanical properties Si can enhance graphitization in the composition range of forming a graphite, with the result that castability and workability can be improved. More, Si improves strength and ductility regardless of a graphite formation.
  • Si exceeds 10 at.% of the above range, elongation deteriorates and brittleness will be caused.
  • the addition of 0.2 at.% or more of Ti, V, Cr, Ta, W, Nb and Mn as the graphitizer can enhance graphitization in the composition range of forming the graphite, with the result that castability and workability can be improved with increasing strength and ductility of the matrix. More, strength can be improved by dispersing the formed carbides.
  • the addition of the elements exceeds 2 at.%, the carbides become excessive, with the result that ductility also deteriorates with the decreasing workability due to hardening. Therefore, the elements are limited to the range of from 0.2 to 2.0 at.% in the invention.
  • B and Zr are limited to the range of from 0.2 to 2.0 at.% and P is limited to the range of from 0.01 to 2.0 at.%.
  • the addition of 0.2 at.% or more of Ni and Cu can enhance graphitization in the composition range of forming the graphite, with the result that castability and workability with increasing strength and ductility of the matrix.
  • the elements are limited to the range of from 0.2 to 5.0 at.% in the invention.
  • the addition of 0.1 at.% or more of Ti, V, Cr, Ta, B, Mo, Sm, Sn, FeB, TaB2, TiB2, HfC, TiC, Ag, Ca, Co, Ge, Hf, P, Th, B4C, NbB2, Mo2C, VC, Cr2N, Fe3N, Fe4N, TiN and VN can refine the structure, with the result that strength can be improved with preventing casting defects, such as cracks, segregation or the like. On the other hand, the effect will be saturated if the addition exceeds 2 at.%.
  • the addition of 0.1 at.% or more of Ti, Zr, Ce, Er, Gd, Nd, Dy, La, Pr, Y, BaAl4 and Fe4N softens the structure, with the result that heat fatigue strength can be improved, and further workability can also be improved due to increasing elongation. On the other hand, the effect can be saturated if the addition exceeds 2 at.%. More, the elements of the above may be added as a misch metal.
  • Mg enables elongation to increase, and heat fatigue of the material to improve.
  • Bal. 23.1 17.0 12 4.7 1.3 Bal. 14.9 13 3.8 5.7 Bal. 15.3 14 4.2 16.1 Bal. 14.3 Comp. Ex. 15 30.5 0 Bal. 20.5 16 30.1 9.8 Bal. 18.3 17 34.7 0.9 Bal. 22.7 18 37.1 11.3 Bal. 23.1
  • the average coefficients of linear thermal expansion are 14.3 to 17.0 which are better than the average coefficients of linear thermal expansions 18.3 to 23.1 for Comp.Ex. Nos. 15 to 18.
  • the average coefficient of linear thermal expansion becomes excessively large and equal to or larger than that of the austenitic cast iron as a heat resisting material, rendering the material unsuitable for use as a heat resisting material.
  • the transformation temperatures during cooling are 835°C or above which are higher, i.e., better than the transformation temperatures 693 to 748°C for Comp. Ex. Nos. 29 to 33.
  • the transformation temperature is above 800°C which exceeds that of high-silicon heat-resisting cast iron.
  • the coefficient of thermal expansion is low, i.e., excellent, indicating that the materials of the present invention have good properties as a heat resisting material.
  • the tensile strengths at room temperature are 489 to 959 MPa which are better than the tensile strengths at room temperature 96 to 195 MPa for Comp.Ex. Nos. 42 to 44. Specifically, when the C content exceeds 12 at.%, the tensile strength at room temperature is lowered. For heat resisting materials, the tensile strength at a high temperature is about 1/3 of that at room temperature. This value is proportional to that at room temperature. Further, as demonstrated in Example 1, the coefficient of thermal expansion is low, i.e., excellent.
  • the transformation temperatures are 808°C or above during cooling and 837°C or above during heating, respectively, which are higher, i.e., better than the transformation temperatures of 730°C or under during cooling and 820°C or under during heating for Comp. Ex. Nos. 51 and 52. Therefore, as mentioned above, the limited temperature of the heat resistance application rises, with the result that the heat resistance can be improved and the graphitization can be enhanced.
  • the graphite amount of adding the graphitizer in the present invention is 3.1 to 7.5%
  • the Comp. Ex. without adding the graphitizer has 2.6% of the graphite amount, i.e., the effect of the graphitizer according to the present invention is remarkably exhibited in the scope of the present invention.
  • Figs. 5(a) to 5(c) show the metallic structure photographs of three magnifications after casting of Fe - 10% at.% Al - 2 at.% C alloy without addition, of Fe - 10 at.% Al - 2 at.% C alloy adding 0.8 at.% TiB2 and of Fe - 10 at.% Al - 2 at.% alloy adding 1.9 at.% TiB2, respectively. From these photographs, the above effect of refining can remarkably exhibited in the scope of the present invention.
  • the hardness values are 221 to 306 of Vickers Hardness, i.e., better than the hardness value 334 of Vickers Hardness without addition. Namely, the effect of improving softening and ductility can remarkably exhibited in the scope of the present invention.
  • the elongation values are 3.9 to 8.1%, i.e., better than the elongation values 0.4 to 2.7% without addition. Namely, the effect of improving elongation can remarkably exhibited by adding Mg to the alloys according to the present invention.
  • the materials of the present invention despite the fact that they are mainly ternary alloys consisting of Fe, Al, and C without use an amount of expensive alloying elements, such as Cr and Ni, have excellent high-temperature heat resisting properties, i.e., low coefficient of linear thermal expansion and enhanced transformation temperature and excellent tensile strength, and, hence, can be applied to members to be used at higher temperatures.
  • the materials of the present invention have a transformation temperature of 800°C or above, rendering the materials of the present invention suitable for use in high temperature environments in an exhaust system and other systems of vehicles.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Manufacture Of Alloys Or Alloy Compounds (AREA)
  • Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)

Abstract

A high heat-resisting iron-base alloy characterized by having a composition which is represented by the general formula: FexAlyCz, wherein y and z are, in terms of atomic %, 1% ≦ y(at.%) ≦ 28% and 0% < z(at.%) ≦ 24%, respectively, with x constituting the balance, and falls within the area formed by connecting points A, B, C, and D shown in Fig. 1.

Description

    BACKGROUND OF THE INVENTION 1. Field of the Invention
  • The present invention relates to an Fe-Al-C-base alloy and more particularly to an iron-base alloy, having excellent heat resistance, for use at high temperatures.
    • 2. Prior Art
  • An ever-increasing tendency toward the use of heat resisting materials in an exhaust system and other systems of automobiles under severer service conditions in recent years has necessitated the prevention of high temperature deformation and a lowering in tensile strength of these materials in higher temperature environments. Further, these materials should have such properties as high-temperature strength, small creep elongation, and excellent thermal fatigue resistance and impact resistance. For this reason, expensive alloying elements, such as Cr and Ni, have hitherto been used in the art.
  • Such high heat resisting iron-base materials known in the art include, for example, SCH-base heat resisting steel casting materials (JIS G5122) and FCDA-base nodular graphite austenitic iron castings (JIS G5510). When these materials are classified according to heat resistance properties, high-silicon nodular graphite cast iron can be first mentioned. For this material, since the transformation temperature is so low that it is difficult to use the material in a higher temperature region of 800°C or above. For this reason, a ferrite cast steel has been used as a material for use in this higher temperature region. Cr incorporated in an amount of not less than 15% in this material, however, is expensive. Further, austenitic cast iron can also be mentioned as a material for use at high temperatures. In this material as well, Cr or Ni, which is an expensive alloying element, is used.
  • On the other hand, in recent years, lightweight and high melting point of an FeAl intermetallic compound have attracted attention, and the development of an alloy system of this compound has been put forward. For example, Japanese Unexamined Patent Publication (Kokai) No. 3-226547, which has been filed by the applicant of the present invention, discloses, as a high toughness material, an Fe-Al-base intermetallic compound material having an Al content of 36.8 to 49.4 at.%. As with the conventional heat resisting materials, this intermetallic compound material contains Cr from the viewpoint of improving the toughness.
  • Regarding the prior art in this field, Japanese Unexamined Patent Publication (Kokai) No. 56-58950 discloses an alloy, having an Al content of 0.72 to 18.7 at.%, for a heat treatment roll having an improved pickup property. Japanese Unexamined Patent Publication (Kokai) No. 57-126949 discloses an alloy, having an Al content of 17 to 32.7 at.%, as a vibration control alloy which causes regular-irregular transformation. In addition, Japanese Unexamined Patent Publication (Kokai) No. 57-203750 discloses an alloy, having an Al content of 0.2 to 7.4 at.% and a C content of 1.83 to 8.3 at.%, as a magnetic material for a composite of magnetic material/non-magnetic material, Japanese Unexamined Patent Publication (Kokai) No. 62-270452 discloses an alloy, having an Al content of 13.5 to 37.3 at.% and a C content of 0.004 to 3.2 at.%, for a carbon fiber-reinforced concrete structure with a reinforcing bar being embedded therein, and Japanese Unexamined Patent Publication (Kokai) No. 6-25800 discloses an alloy, having an Al content of 25 to 50 at.%, for a high-strength and abrasion-resisting material with a carbide being dispersed therein. None of the above known techniques, however, disclose an Fe-Al-C ternary alloy as at least heat resisting material.
  • It is reported that, in general, in terms of a phase diagram of an alloy, for an Fe-Al-base alloy, ferrite is formed when the Al content is not more than 54 at.%, while for an Fe-Al-C ternary alloy, the percentage of graphitization increases with increasing the Al content until the Al content reaches about 5 at.% and decreases with further increase in the Al content and, thereafter, a carbide phase and a ferrite phase having relatively high hardness are formed.
  • Regarding the heat resistance of Al cast iron, it is known that, by virtue of a strong Al₂O₃ film formed by Al incorporated on the surface of the Al cast iron, the Al cast iron does not permit the penetration of oxygen thereinto, has excellent oxidation resistance at a high temperature, is less likely to cause growth of a carbide, and has excellent heat resistance (see, for example, "Tokushu Chutetsu (Special Cast Iron)," 3rd edition, published by Nikkan Kogyo Shimbun, Ltd., 1960).
  • The above conventional materials, however, do not have satisfactory heat resistance at higher temperatures and, further, have problems associated with the production thereof. For this reason, the development of an iron-base material, which contains no expensive alloying elements, such as Cr and Ni, is less expensive, and has excellent high-temperature heat resistance, has been desired in the art.
    • SUMMARY OF THE INVENTION
  • An object of the present invention is to study an Fe-Al-C-base alloy as a ternary alloy with a view to solving the above problems of an Fe-Al-base alloy and to provide a high heat-resisting iron-base alloy having lowered average coefficient of linear expansion, enhanced transformation temperature, and excellent tensile strength.
  • Another object of the present invention is to provide a high heat-resisting iron-base alloy mainly consisting of Fe, Al, and C alone without use of conventional expensive alloying elements, such as Cr and Ni, which high heat-resisting iron-base alloy is inexpensive and has improved mechanical properties equal or superior to the conventional alloys.
  • A further object of the present invention is to provide a high heat-resisting iron-base alloy through study of ingredients capable of reducing the problem associated with the production of an Fe-Al-base alloy, particularly improving the castability.
  • The above objects can be attained by a high heat-resisting iron-base alloy mentioned as the following.
    • (1) A high heat-resisting iron-base alloy is characterized in essentially consisting of a composition, in terms of atomic %, which is represented by the general formula: FexAlyCz, wherein y and z are 1% ≦ y(at.%) ≦ 28%, and 0% < z(at.%) ≦ 24%, respectively, with x being the remainder.
    • (2) The high heat-resisting iron-base alloy according to item (1), wherein y and z fall within the area formed by connecting points A(1, 24), B(1, 0), C(28, 0) and D(28, 24) shown in Fig. 1, provided that for the values on line C: 0% is excluded.
    • (3) The high heat-resisting iron-base alloy according to item (1), wherein y and z further satisfy the inequalities (1) to (4) hereunder;
    5y - 8z ≧ 25 (here, z < 5 at.%)
    Figure imgb0001
     5y - 2z ≧ 55 (5 at.% ≦ z < 10 at.%)
    Figure imgb0002
     y ≧ 15 (10 at.% ≦ z < 15 at.%)
    Figure imgb0003
     y + 3z ≧ 60 (15 at.% ≦ z)
    Figure imgb0004
    • (4) The high heat-resisting iron-base alloy according to item (1), wherein y and z fall within the area formed by connecting points A(1, 24), E(1, 19), F(15, 15), G(15, 10), H(13, 5), I(5, 0), C(28, 0) and D(28, 24) shown in Fig. 2, provided that for the values on line C: 0% is excluded.
    • (5) The high heat-resisting iron-base alloy according to item (1), wherein y and z further satisfy the inequality (5) hereunder; z ≦ 12 at.%
      Figure imgb0005
    • (6) The high heat-resisting iron-base alloy according to item (1), wherein y and z fall within the area formed by connecting points J(1, 12) B(1, 0), C(28, 0) and K(28, 12) shown in Fig. 3, provided that for the values on line C: 0% is excluded.
    • (7) The high heat-resisting iron-base alloy characterized in essentially consisting of a composition, in terms of atomic %, which is represented by the general formula: FexAlySiz1Cz2, wherein y, z₁ and z₂ fall within the area formed by connecting points A(1, 24), J(1, 12), L(8, 10), M(7, 5), B(1, 0), C(28, 0) and D(28, 24) shown in Fig. 4, in which ztotal = z₂ + 0.75z₁, and 0.2 at.% ≦ z₁ ≦ 10 at.%.
    • (8) The high heat-resisting iron-base alloy according to any one of items (1) to (7) further comprising a graphitizer.
    • (9) The high heat-resisting iron-base alloy according to item (8) further comprising 0.2 to 2.0 at.% of at least one element selected from the group of Ti, V, Cr, Ta, W, Nb and Mn as the graphitizer.
    • (10) The high heat-resisting iron-base alloy according to item (8) further comprising 0.2 to 2.0 at.% of one or both of B and Zr as the graphitizer.
    • (11) The high heat-resisting iron-base alloy according to item (8) further comprising 0.01 to 0.2 at.% of P as the graphitizer.
    • (12) The high heat-resisting iron-base alloy according to item (8) further comprising 0.2 to 5.0 at.% of one or both of Ni and Cu as the graphitizer.
    • (13) The high heat-resisting iron-base alloy according to any one of items (1) to (12) further comprising an element or a compound for refining.
    • (14) The high heat-resisting iron-base alloy according to item (13) further comprising 0.1 at.% or more of at least one selected from the group of Ti, V, Cr, Ta, B, Mo, Sm, Sn, FeB, TaB₂, TiB₂, HfC, TiC, Ag, Ca, Co, Ge, Hf, P, Yb, B₄C, NbB₂, Mo₂C, VC, Cr₂N, Fe₃N, Fe₄N, TiN and VN as the element or the compound for refining.
    • (15) The high heat-resisting iron-base alloy according to any one of items (1) to (14) further comprising an element or a compound for improving ductility.
    • (16) The high heat-resisting iron-base alloy according to item (15) further comprising 0.1 at.% or more of at least one selected from the group of Ce, Er, Gd, Nd, Dy, La, Pr, Y, BaAl₄ and Fe₄N as the element or the compound for improving ductility.
    BRIEF DESCRIPTION OF THE DRAWINGS
  • Fig. 1 is a diagram showing the scope of the first invention in terms of the relationship between the C content and the Al content.
  • Fig. 2 is a diagram showing the scope of the second invention in terms of the relationship between the C content and the Al content.
  • Fig. 3 is a diagram showing the scope of the third invention in terms of the relationship between the C content and the Al content.
  • Fig. 4 is a diagram showing the scope of the fourth invention in terms of the relationship between the C + 0.75Si amount and the Al content.
  • Figs. 5(a) to 5(c) are metallic structure photographs of Fe-10 at.% Al-2 at.% C alloy showing the effect of the refining element according to thirteenth and fourteenth claims, Fig. 5(a) shows without addition, Fig. 5(b) shows with addition of 0.8 at.% TiB₂, Fig. 5(c) shows with addition of 1.9 at.% TiB₂.
    • DESCRIPTION OF THE PREFERRED EMBODIMENT
  • The alloy of the first invention has a low coefficient of thermal expansion and creates neither significant strain nor significant stress even under high temperature environments and, hence, can be an excellent heat resisting material.
  • The alloy of the second invention has a high transformation temperature and creates neither significant expansion nor significant shrinkage even under high temperature conditions and, hence, can be an excellent heat resisting material.
  • The alloy of the third invention has a low coefficient of thermal expansion and, in addition, high tensile strength and, hence, can be an excellent heat resisting material.
  • The reasons for the limitation of ingredients specified in the present invention will now be described.
  • In the first invention, when the Al content is less than 1 at.%, the oxidation resistance becomes unsatisfactory, while when it exceeds 28 at.%, the coefficient of thermal expansion becomes large, making it difficult to use the alloy as a heat resisting material. When the C content exceeds 24 at.%, the melting point of the alloy is high, making it very difficult to melt the alloy. The lower limit of the C content is more than 0 at.% exclusive of the value on the line C: of 0 at.% in Fig. 1.
  • The alloy of the second invention should satisfy both the requirement specified in the first invention and a requirement represented by the following inequalities. Points E, F, G, H, and I in Fig. 2 are each a boundary point where two regions cross. 5y - 8z ≧ 25 (here, z < 5 at.%)
    Figure imgb0006
     5y - 2z ≧ 55 (5 at.% ≦ z < 10 at.%)
    Figure imgb0007
     y ≧ 15 (10 at.% ≦ z < 15 at.%)
    Figure imgb0008
     y + 3z ≧ 60 (15 at.% ≦ z)
    Figure imgb0009
    wherein y and z represent a value of Al at.% and a value of C at.%, respectively, and the formulae in parentheses represent applicable content regions in respective inequalities.
  • The lower limit of the C content is more than 0 at.% exclusive of the value on the line C: of 0 at.% in Fig. 2.
  • The above limitations are provided because when the material is heated from room temperature to a high temperature, if the material brings about transformation, significant expansion or shrinkage occurs at the transformation point. For this reason, the lowest temperature at which the transformation occurs is the upper limit of the service temperature. In the content ranges specified above, the transformation temperature of the material is 800°C or above, indicating that the material can be used as a heat resisting material at a temperature up to 800°C or above and, hence, is suitable for use in high temperature environments of exhaust systems and other systems of vehicles.
  • The alloy of the third invention should satisfy the requirement specified in the first invention and a requirement represented by the following formula, that is, has a composition falling within the range shown in Fig. 3. C ≦ 12 at.%
    Figure imgb0010
  • This limitation is provided because when the C content exceeds 12 at.%, the tensile strength cannot be provided, rendering the strength of the alloy unsatisfactory.
  • Furthermore, the properties, such as resistance to oxidation, transformation temperature, or the like, are also important for a heat-resisting material besides strength, ductility and fatigue strength at high temperature. Therefore, in the fourth invention, Fe-Al-Si alloy falls within the area formed by connecting points A, J, L, M, B, C and D shown in Fig. 4 and satisfies the formulas hereunder. z total = C + 0.75Si
    Figure imgb0011
     0.2 at.% ≦ Si ≦ 10 at.%
    Figure imgb0012
  • Namely, the compositions of Al, C and Si are in the range of satisfying the above three conditions. In the range, Si effects changing the transformation temperature, with the result that the heat resistance can be improved by rising the limited temperature of the heat resistance application. More, Si improves the resistance to oxidation, with the result that the heat resistance of the material can be improved. Furthermore, in mechanical properties, Si can enhance graphitization in the composition range of forming a graphite, with the result that castability and workability can be improved. More, Si improves strength and ductility regardless of a graphite formation. However, when the addition of Si exceeds 10 at.% of the above range, elongation deteriorates and brittleness will be caused.
  • Next, other ingredients according to the invention will be explained below. First, the addition of 0.2 at.% or more of Ti, V, Cr, Ta, W, Nb and Mn as the graphitizer can enhance graphitization in the composition range of forming the graphite, with the result that castability and workability can be improved with increasing strength and ductility of the matrix. More, strength can be improved by dispersing the formed carbides. On the other hand, when the addition of the elements exceeds 2 at.%, the carbides become excessive, with the result that ductility also deteriorates with the decreasing workability due to hardening. Therefore, the elements are limited to the range of from 0.2 to 2.0 at.% in the invention.
  • More, the addition of 0.2 at.% or more of B and Zr or 0.01 at.% or more of P can enhance graphitization in the composition range of forming the graphite, with the result that castability and workability can be improved with increasing strength and ductility of the matrix. More, strength can be improved by dispersing the formed iron compounds. On the other hand, when the addition of the elements exceeds 2 at.%, the iron compounds become excessive, with the result that ductility also deteriorates with decreasing workability due to hardening. Therefore, B and Zr are limited to the range of from 0.2 to 2.0 at.% and P is limited to the range of from 0.01 to 2.0 at.%.
  • Furthermore, the addition of 0.2 at.% or more of Ni and Cu can enhance graphitization in the composition range of forming the graphite, with the result that castability and workability with increasing strength and ductility of the matrix. On the other hand, when addition of the elements exceeds 5 at.%, the austenitizing tendency becomes great, with the result that the transformation temperature lowers. Therefore, the elements are limited to the range of from 0.2 to 5.0 at.% in the invention.
  • Next, the addition of 0.1 at.% or more of Ti, V, Cr, Ta, B, Mo, Sm, Sn, FeB, TaB₂, TiB₂, HfC, TiC, Ag, Ca, Co, Ge, Hf, P, Th, B₄C, NbB₂, Mo₂C, VC, Cr₂N, Fe₃N, Fe₄N, TiN and VN can refine the structure, with the result that strength can be improved with preventing casting defects, such as cracks, segregation or the like. On the other hand, the effect will be saturated if the addition exceeds 2 at.%. More, the addition of 0.1 at.% or more of Ti, Zr, Ce, Er, Gd, Nd, Dy, La, Pr, Y, BaAl₄ and Fe₄N softens the structure, with the result that heat fatigue strength can be improved, and further workability can also be improved due to increasing elongation. On the other hand, the effect can be saturated if the addition exceeds 2 at.%. More, the elements of the above may be added as a misch metal.
  • Furthermore, the addition of Mg enables elongation to increase, and heat fatigue of the material to improve.
  • The present invention will now be described in more detail with reference to the following examples and comparative examples.
    • EXAMPLE Example 1
  • Alloys having compositions specified in Table 1 were prepared as examples of the first invention and comparative examples. In Table 1, Ex. Nos. 1 to 14 of the present invention are alloys having compositions specified in claim 2 shown in Fig. 1, and Comp. Ex. Nos. 15 to 18 are alloys having compositions outside this composition range.
  • These alloys were subjected to measurement of the coefficient of linear thermal expansion at 40 to 800°C, and the results are expressed in terms of average coefficient of linear thermal expansion and are also given in Table 1. Table 1
    Classification No. Ingredients (at.%) Average coefficient of linear thermal expansion (40-800°C) (x10⁻⁶/°C)
    Al C Fe
    Ex. of inv. 1 26.3 10.4 Bal. 16.3
    2 25.0 14.7 Bal. 15.8
    3 20.3 0.1 Bal. 14.9
    4 18.9 5.1 Bal. 15.8
    5 20.1 15.6 Bal. 15.3
    6 21.8 22.4 Bal. 15.6
    7 15.2 0.9 Bal. 14.5
    8 14.8 10.9 Bal. 16.9
    9 8.8 0.1 Bal. 14.6
    10 11.0 5.3 Bal. 15.1
    11 9.8 15.0 Bal. 17.0
    12 4.7 1.3 Bal. 14.9
    13 3.8 5.7 Bal. 15.3
    14 4.2 16.1 Bal. 14.3
    Comp. Ex. 15 30.5 0  Bal. 20.5
    16 30.1 9.8 Bal. 18.3
    17 34.7 0.9 Bal. 22.7
    18 37.1 11.3 Bal. 23.1
  • As can be seen from Table 1, for Ex. Nos. 1 to 14 of the present invention, the average coefficients of linear thermal expansion are 14.3 to 17.0 which are better than the average coefficients of linear thermal expansions 18.3 to 23.1 for Comp.Ex. Nos. 15 to 18. Specifically, when the Al content exceeds 28 at.%, the average coefficient of linear thermal expansion becomes excessively large and equal to or larger than that of the austenitic cast iron as a heat resisting material, rendering the material unsuitable for use as a heat resisting material.
  • When a material to be used at a high temperature has a high coefficient of thermal expansion as in the above material, exposure of the material alternately to a high temperature and a low temperature results in significant expansion/shrinkage of the material. This expansion/shrinkage creates significant strain and stress in adjacent components joined to the member used in a high temperature environment. Further, the material per se also brings about significant strain and stress, because it undergoes constraint by adjacent components, and, in some cases, is broken. For this reason, the lower the coefficient of thermal expansion of the heat resisting material, the better the results.
    • Example 2
  • Alloys having compositions specified in Table 2 were prepared as examples of the second invention and comparative examples. In Table 2, Ex. Nos. 19 to 28 of the present invention are alloys having compositions specified in claim (4) shown in Fig. 2, and Comp.Ex. Nos. 29 to 33 are alloys having compositions outside this composition range.
  • These alloys were subjected to measurement of the transformation temperature, and the results are also given in Table 2. Table 2
    Classification No. Ingredients (at.%) Transformation temp. during cooling (°C) Transformation temp. during heating (°C)
    Al C Fe
    Ex. of inv. 19 8.8 0.1 Bal. >1000 >1000
    20 9.7 1.6 Bal. >1000 >1000
    21 14.0 5.1 Bal. 855 887
    22 15.3 9.2 Bal. 838 880
    23 16.1 14.7 Bal. 835 855
    24 15.2 0.9 Bal. 920 940
    25 20.3 0.1 Bal. >1000 >1000
    26 18.9 5.1 Bal. >1000 >1000
    27 20.1 15.6 Bal. >1000 >1000
    28 21.8 22.4 Bal. >1000 >1000
    Comp. Ex. 29 4.7 1.3 Bal. 693 768
    30 11.0 5.3 Bal. 715 775
    31 12.4 8.9 Bal. 748 778
    32 9.8 15.0 Bal. 746 848
    33 4.2 16.1 Bal. 740 768
  • As can be seen from Table 2, for Ex. Nos. 19 to 28 of the present invention, the transformation temperatures during cooling are 835°C or above which are higher, i.e., better than the transformation temperatures 693 to 748°C for Comp. Ex. Nos. 29 to 33. Specifically, when the composition falls within the range specified in claim (4) shown in Fig. 2, the transformation temperature is above 800°C which exceeds that of high-silicon heat-resisting cast iron. Further, as demonstrated in Example 1, the coefficient of thermal expansion is low, i.e., excellent, indicating that the materials of the present invention have good properties as a heat resisting material.
    • Example 3
  • Alloys having compositions specified in Table 3 were prepared as examples of the third invention and comparative examples. In Table 3, Ex. Nos. 34 to 41 of the present invention are alloys having compositions specified in claim (6) shown in Fig. 3, and Comp. Ex. Nos. 42 to 44 are alloys having compositions outside this composition range.
  • These alloys were subjected to measurement of the tensile strength at room temperature, and the results are also given in Table 3. Table 3
    Classification No. Ingredients (at.%) Tensile strength (MPa)
    Al C Fe
    Ex. of inv. 34 3.8 5.7 Bal. 959
    35 4.1 11.3 Bal. 652
    36 11.0 5.3 Bal. 854
    37 10.9 10.7 Bal. 494
    38 14.0 5.1 Bal. 455
    39 14.8 10.9 Bal. 636
    40 18.9 5.1 Bal. 489
    41 20.3 0.1 Bal. 501
    Comp. Ex. 42 4.2 16.1 Bal. 140
    43 9.8 15.0 Bal. 195
    44 16.1 14.7 Bal. 96
  • As can be seen from Table 3, for Ex. Nos. 34 to 41 of the present invention, the tensile strengths at room temperature are 489 to 959 MPa which are better than the tensile strengths at room temperature 96 to 195 MPa for Comp.Ex. Nos. 42 to 44. Specifically, when the C content exceeds 12 at.%, the tensile strength at room temperature is lowered. For heat resisting materials, the tensile strength at a high temperature is about 1/3 of that at room temperature. This value is proportional to that at room temperature. Further, as demonstrated in Example 1, the coefficient of thermal expansion is low, i.e., excellent. These facts indicate that the materials of the present invention have good properties as a heat resisting material.
    • Example 4
  • Alloys having compositions specified in Table 4 were prepared as examples of the fourth invention and comparative examples. In Table 4, Ex. Nos. 45 to 50 of the present invention are alloys having compositions specified in claim 6 shown in Fig. 4, and Comp. Ex. Nos. 51 and 52 are alloys having compositions outside this composition range.
  • These alloys were subjected to measurement of the transformation temperature during cooling and heating, and the results are also given in Table 4. Table 4
    Classification No. Ingredients (at.%) Transformation temp. during cooling (°C) Transformation temp. during heating (°C)
    Al ztotal C Si Fe
    Ex. of inv. 45 8.1 4.2 0.4 5.0 Bal. 810 858
    46 10.0 6.9 4.0 3.8 Bal. 808 837
    47 7.1 12.4 7.3 6.8 Bal. 823 848
    48 20.1 5.1 4.0 1.5 Bal. 911 948
    49 22.3 14.0 10.1 5.2 Bal. >1000 >1000
    50 20.2 19.9 14.9 6.7 Bal. >1000 >1000
    Comp. Ex. 51 4.0 5.2 3.9 1.7 Bal. 730 820
    52 3.1 10.0 8.4 2.1 Bal. 708 785
  • As can be seen from Table 4, for Ex. Nos. 45 to 50 of the present invention, the transformation temperatures are 808°C or above during cooling and 837°C or above during heating, respectively, which are higher, i.e., better than the transformation temperatures of 730°C or under during cooling and 820°C or under during heating for Comp. Ex. Nos. 51 and 52. Therefore, as mentioned above, the limited temperature of the heat resistance application rises, with the result that the heat resistance can be improved and the graphitization can be enhanced.
    • Example 5
  • Next, the examples of improving the properties by adding other ingredients according to the present invention will be explained below.
  • First, as the examples of the graphitizer, alloys having compositions specified in Table 5 were prepared as examples of adding the graphitizer and comparative examples. These alloys were subjected to measurement of graphite amount after casting, and the results are also given in Table 5. Table 5
    Classification Ingredients (at.%) Graphite amount (%)
    Al C Added element, amount Fe
    Without addition 18.9 15.2 No-addition Bal. 2.6
    With addition 16.8 15.2 Ti 0.3 Bal. 3.5
    21.5 14.8 V 0.5 Bal. 5.8
    18.1 14.6 Cr 0.5 Bal. 4.8
    17.5 15.4 Ta 0.4 Bal. 7.5
    19.0 13.9 W 0.2 Bal. 4.0
    20.1 14.5 Nb 0.5 Bal. 3.4
    18.7 14.1 Mn 0.4 Bal. 3.2
    18.5 14.2 B 0.6 Bal. 3.6
    18.4 14.9 Zr 0.5 Bal. 3.1
    19.1 15.6 Ni 0.8 Bal. 4.6
    20.3 15.1 Cu 0.8 Bal. 3.1
    19.5 14.6 P 0.5 Bal. 6.0
  • As can be seen from Table 5, although the graphite amount of adding the graphitizer in the present invention is 3.1 to 7.5%, the Comp. Ex. without adding the graphitizer has 2.6% of the graphite amount, i.e., the effect of the graphitizer according to the present invention is remarkably exhibited in the scope of the present invention.
  • Next, as examples adding the element for refining, the examples adding TiB₂ are shown in Figs. 5(a) to 5(c). Figs. 5(a) to 5(c) show the metallic structure photographs of three magnifications after casting of Fe - 10% at.% Al - 2 at.% C alloy without addition, of Fe - 10 at.% Al - 2 at.% C alloy adding 0.8 at.% TiB₂ and of Fe - 10 at.% Al - 2 at.% alloy adding 1.9 at.% TiB₂, respectively. From these photographs, the above effect of refining can remarkably exhibited in the scope of the present invention.
  • Furthermore, as examples of ingredients for improving softening and ductility, alloys having compositions specified in Table 6 were prepared with addition and without addition of the element. These alloys were subjected to measurement of hardness after casting, and the results are also given in Table 6. Table 6
    Classification Ingredients (at.%) Hardness
    Al C Added element, amount Fe Hv (20 kg)
    Without addition 10.1 5.0 No-addition Bal. 334
    With addition 9.8 4.9 Ti 1.6 Bal. 302
    9.7 5.1 Zr 1.5 Bal. 306
    10.2 5.2 Ce 1.3 Bal. 244
    9.7 4.9 Er 1.5 Bal. 253
    9.6 5.3 Gd 1.6 Bal. 231
    9.8 5.2 Nd 1.4 Bal. 288
    10.1 5.1 Dy 1.7 Bal. 274
    9.9 5.0 misch metal 1.3 Bal. 221
    10.3 5.3 La 1.7 Bal. 282
    9.8 4.9 Pr 1.6 Bal. 231
    9.5 5.1 Y 1.7 Bal. 301
    9.6 5.2 BaAl₄ 1.3 Bal. 325
    9.7 5.3 Fe₄N 1.4 Bal. 299
  • As can be seen from Table 6, for alloys with addition of the present invention, the hardness values are 221 to 306 of Vickers Hardness, i.e., better than the hardness value 334 of Vickers Hardness without addition. Namely, the effect of improving softening and ductility can remarkably exhibited in the scope of the present invention.
  • Furthermore, as examples of adding Mg, alloys having compositions specified in Table 7 were prepared with addition and without addition of Mg. These alloys were subjected to measurement of tensile strength and elongation after casting, and the results are also given in Table 7. Table 7
    Classification Ingredients (at.%) Tensile strength (MPa) Elongation (%)
    Al C Si Mg Fe
    Without addition 11.0 5.3 - - Bal. 854 2.7
    10.1 15.3 - - Bal. 304 0.8
    4.2 16.1 - - Bal. 140 0.4
    With addition 11.3 5.1 2.1 0.06 Bal. 976 4.2
    9.7 14.9 6.5 0.04 Bal. 669 3.9
    4.0 15.7 4.7 0.06 Bal. 365 8.1
  • As can be seen from Table 7, for alloys with addition of the present invention, the elongation values are 3.9 to 8.1%, i.e., better than the elongation values 0.4 to 2.7% without addition. Namely, the effect of improving elongation can remarkably exhibited by adding Mg to the alloys according to the present invention.
  • The materials of the present invention, despite the fact that they are mainly ternary alloys consisting of Fe, Al, and C without use an amount of expensive alloying elements, such as Cr and Ni, have excellent high-temperature heat resisting properties, i.e., low coefficient of linear thermal expansion and enhanced transformation temperature and excellent tensile strength, and, hence, can be applied to members to be used at higher temperatures. In particular, the materials of the present invention have a transformation temperature of 800°C or above, rendering the materials of the present invention suitable for use in high temperature environments in an exhaust system and other systems of vehicles.

Claims (16)

  1. A high heat-resisting iron-base alloy characterized in essentially consisting of a composition, in terms of atomic %, which is represented by the general formula: FexAlyCz, wherein y and z are 1% ≦ y(at.%) ≦ 28% and 0% < z(at.%) ≦ 24%, respectively, with x being the remainder.
  2. A high heat-resisting iron-base alloy according to claim 1, wherein y and z fall within the area formed by connecting points A(1, 24), B(1, 0), C(28, 0) and D(28, 24) shown in Fig. 1, provided that values on line C: of 0% are excluded.
  3. A high heat-resisting iron-base alloy according to claim 1, wherein y and z further satisfy the inequalities (1) to (4) hereunder; 5y - 8z ≧ 25 (here, z < 5 at.%)
    Figure imgb0013
     5y - 2z ≧ 55 (5 at.% ≦ z < 10 at.%)
    Figure imgb0014
     y ≧ 15 (10 at.% ≦ z < 15 at.%)
    Figure imgb0015
     y + 3z ≧ 60 (15 at.% ≦ z)
    Figure imgb0016
  4. A high-resisting iron-base alloy according to claim 1, wherein y and z fall within the area formed by connecting points A(1, 24), E(1, 19), F(15, 15), G(15, 10), H(13, 5), I(5, 0), C(28, 0) and D(28, 24) shown in Fig. 2, provided that values on line C: of 0% are excluded.
  5. A high heat-resisting iron-base alloy according to claim 1, wherein y and z further satisfy the inequality (5) hereunder; z ≦ 12 at.%
    Figure imgb0017
  6. A high heat-resisting iron-base alloy according to claim 1, wherein y and z fall within the area formed by connecting points J(1, 12) B(1, 0), C(28, 0) and K(28, 12) shown in Fig. 3, provided that values on line C: of 0% are excluded.
  7. A high heat-resisting iron-base alloy characterized in essentially consisting of a composition, in terms of atomic %, which is represented by the general formula: FexAlvSiz1Cz2, wherein y, z₁ and z₂ fall within the area formed by connecting points A(1, 24), J(1, 12), L(8, 10), M(7, 5), B(1, 0), C(28, 0) and D(28, 24) shown in Fig. 4, in which ztotal = z₂ + 0.75z₁, and 0.2 at.% ≦ z₁ ≦ 10 at.%.
  8. A high heat-resisting iron-base alloy according to any one of claims 1 to 7 further comprising a graphitizer.
  9. A high heat-resisting iron-base alloy according to claim 8 further comprising 0.2 to 2.0 at.% of at least one element selected from the group of Ti, V, Cr, Ta, W, Nb and Mn as the graphitizer.
  10. A high heat-resisting iron-base alloy according to claim 8 further comprising 0.2 to 2.0 at.% of one or both of B and Zr as the graphitizer.
  11. A high heat-resisting iron-base alloy according to claim 8 further comprising 0.01 to 0.2 at.% of P as the graphitizer.
  12. A high heat-resisting iron-base alloy according to claim 8 further comprising 0.2 to 5.0 at.% of one or both of Ni and Cu as the graphitizer.
  13. A high heat-resisting iron-base alloy according to any one of claims 1 to 12 further comprising an element or a compound for refining.
  14. A high heat-resisting iron-base alloy according to claim 13 further comprising 0.1 at.% or more of at least one selected from the group of Ti, V, Cr, Ta, B, Mo, Sm, Sn, FeB, TaB₂, TiB₂, HfC, TiC, Ag, Ca, Co, Ge, Hf, P, Yb, B₄C, NbB₂, Mo₂C, VC, Cr₂N, Fe₃N, Fe₄N, TiN and VN as the element or the compound for refining.
  15. A high heat-resisting iron-base alloy according to any one of claims 1 to 14 further comprising an element or a compound for improving ductility.
  16. A high heat-resisting iron-base alloy according to claim 15 further comprising 0.1 at.% or more of at least one selected from the group of Ce, Er, Gd, Nd, Dy, La, Pr, Y, BaAl₄ and Fe₄N as the element or the compound for improving ductility.
EP95305233A 1994-08-05 1995-07-26 High heat-resisting iron-base alloy Withdrawn EP0695811A1 (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
JP18463694 1994-08-05
JP184636/94 1994-08-05
JP20507895A JPH08100243A (en) 1994-08-05 1995-07-20 Highly heat resistant iron-bas alloy
JP205078/95 1995-07-20

Publications (1)

Publication Number Publication Date
EP0695811A1 true EP0695811A1 (en) 1996-02-07

Family

ID=26502608

Family Applications (1)

Application Number Title Priority Date Filing Date
EP95305233A Withdrawn EP0695811A1 (en) 1994-08-05 1995-07-26 High heat-resisting iron-base alloy

Country Status (2)

Country Link
EP (1) EP0695811A1 (en)
JP (1) JPH08100243A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999009334A2 (en) * 1997-08-14 1999-02-25 SCHWäBISCHE HüTTENWERKE GMBH Composite material with a high proportion of intermetallic phases, preferably for friction bodies
US7534314B2 (en) 2005-06-13 2009-05-19 Daimler Ag High carbon steel with superplasticity
DE102007056144A1 (en) * 2007-11-16 2009-05-20 Volkswagen Ag Exhaust manifold or turbo-supercharger housings, useful in internal combustion engines, comprises iron-aluminum steel alloy composition comprising aluminum, chromium, elements of carbon, titanium, zirconium or vanadium, boron and niobium
WO2017125147A1 (en) 2016-01-20 2017-07-27 Thyssenkrupp Steel Europe Ag Flat steel product and method for the production thereof

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3589797B2 (en) * 1996-06-21 2004-11-17 株式会社神戸製鋼所 Wear resistant high Mn cast steel
JP4852737B2 (en) * 2004-09-27 2012-01-11 国立大学法人 千葉大学 Method for producing recycled Fe-Al composite material
JP2020084294A (en) * 2018-11-30 2020-06-04 株式会社日立製作所 Powder for molding laminate, laminate molded body, and manufacturing method of laminate molded body

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5658950A (en) 1979-10-16 1981-05-22 Kubota Ltd Heat treating roller
JPS56129303A (en) * 1980-03-13 1981-10-09 Tdk Corp Magnetic recording substance
JPS57126949A (en) 1980-06-19 1982-08-06 Kajita Tsunehiro Vibration-damping alloy and method for producing the same
JPS57203750A (en) 1981-06-09 1982-12-14 Nec Corp Alloy for composite magnetic material
US4501612A (en) * 1983-10-27 1985-02-26 The University Of Alabama Compacted graphite cast irons in the iron-carbon-aluminum system
GB2186886A (en) * 1986-02-25 1987-08-26 Nippon Steel Corp Steel composition
JPS62240746A (en) * 1986-04-11 1987-10-21 Yamaha Motor Co Ltd Member of brake to be braked
JPS62270452A (en) 1986-05-15 1987-11-24 新日本製鐵株式会社 Carbon fiber reinforced concrete structure
JPS63109141A (en) * 1986-10-24 1988-05-13 Nissan Motor Co Ltd Wear resistant material
JPH03226547A (en) 1990-01-30 1991-10-07 Toyota Motor Corp High toughness fe-al intermetallic compound material
JPH0625800A (en) 1992-07-06 1994-02-01 Daido Steel Co Ltd High strength and high resistant material

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5658950A (en) 1979-10-16 1981-05-22 Kubota Ltd Heat treating roller
JPS56129303A (en) * 1980-03-13 1981-10-09 Tdk Corp Magnetic recording substance
JPS57126949A (en) 1980-06-19 1982-08-06 Kajita Tsunehiro Vibration-damping alloy and method for producing the same
JPS57203750A (en) 1981-06-09 1982-12-14 Nec Corp Alloy for composite magnetic material
US4501612A (en) * 1983-10-27 1985-02-26 The University Of Alabama Compacted graphite cast irons in the iron-carbon-aluminum system
GB2186886A (en) * 1986-02-25 1987-08-26 Nippon Steel Corp Steel composition
JPS62240746A (en) * 1986-04-11 1987-10-21 Yamaha Motor Co Ltd Member of brake to be braked
JPS62270452A (en) 1986-05-15 1987-11-24 新日本製鐵株式会社 Carbon fiber reinforced concrete structure
JPS63109141A (en) * 1986-10-24 1988-05-13 Nissan Motor Co Ltd Wear resistant material
JPH03226547A (en) 1990-01-30 1991-10-07 Toyota Motor Corp High toughness fe-al intermetallic compound material
JPH0625800A (en) 1992-07-06 1994-02-01 Daido Steel Co Ltd High strength and high resistant material

Non-Patent Citations (5)

* Cited by examiner, † Cited by third party
Title
"Tokushu Chutetsu (Special Cast Iron)", 1960, NIKKAN KOGYO SHIMBUN, LTD.
PATENT ABSTRACTS OF JAPAN vol. 006, no. 006 (E - 089) 14 January 1982 (1982-01-14) *
PATENT ABSTRACTS OF JAPAN vol. 007, no. 053 (C - 154) 3 March 1983 (1983-03-03) *
PATENT ABSTRACTS OF JAPAN vol. 012, no. 117 (C - 487) 13 April 1988 (1988-04-13) *
PATENT ABSTRACTS OF JAPAN vol. 012, no. 353 (C - 530) 21 September 1988 (1988-09-21) *

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999009334A2 (en) * 1997-08-14 1999-02-25 SCHWäBISCHE HüTTENWERKE GMBH Composite material with a high proportion of intermetallic phases, preferably for friction bodies
WO1999009334A3 (en) * 1997-08-14 1999-04-15 Schwaebische Huettenwerke Gmbh Composite material with a high proportion of intermetallic phases, preferably for friction bodies
US7534314B2 (en) 2005-06-13 2009-05-19 Daimler Ag High carbon steel with superplasticity
DE102005027258B4 (en) * 2005-06-13 2013-01-31 Daimler Ag High carbon steel with superplasticity
DE102007056144A1 (en) * 2007-11-16 2009-05-20 Volkswagen Ag Exhaust manifold or turbo-supercharger housings, useful in internal combustion engines, comprises iron-aluminum steel alloy composition comprising aluminum, chromium, elements of carbon, titanium, zirconium or vanadium, boron and niobium
WO2017125147A1 (en) 2016-01-20 2017-07-27 Thyssenkrupp Steel Europe Ag Flat steel product and method for the production thereof

Also Published As

Publication number Publication date
JPH08100243A (en) 1996-04-16

Similar Documents

Publication Publication Date Title
EP0719872B1 (en) Aluminum containing iron-base alloys useful as electrical resistance heating elements
US5298093A (en) Duplex stainless steel having improved strength and corrosion resistance
US4261739A (en) Ferritic steel alloy with improved high temperature properties
EP0556798B1 (en) Clad aluminum alloy material having high-strength, high-corrosion resistance for heat exchanger
EP0381121B1 (en) High-strength heat-resistant steel with improved workability
US20090272469A1 (en) Stainless-steel pipe for oil well and process for producing the same
EP1683885B1 (en) High strength stainless steel pipe for line pipe excellent in corrosion resistance and method for production thereof
US5591391A (en) High chromium ferritic heat-resistant steel
EP0384433A1 (en) Ferritic heat resisting steel having superior high-temperature strength
WO2009158332A2 (en) Ni-co-cr high strength and corrosion resistant welding product and method of preparation
EP0657558A1 (en) Fe-base superalloy
EP0695811A1 (en) High heat-resisting iron-base alloy
JP2636816B2 (en) Alloy tool steel
JP5029942B2 (en) Hot work tool steel with excellent toughness
JPH0555585B2 (en)
JP2968430B2 (en) High strength low thermal expansion alloy
JPS5938365A (en) Heat-resistant cast steel
JP2819906B2 (en) Ni-base alloy for tools with excellent room and high temperature strength
US5242655A (en) Stainless steel
JP2970432B2 (en) High temperature stainless steel and its manufacturing method
EP0816523A1 (en) Low-Cr ferritic steels and low-Cr ferritic cast steels having excellent high-temperature strength and weldability
JP2801832B2 (en) Fe-Cr alloy with excellent workability
JPH11106860A (en) Ferritic heat resistant steel excellent in creep characteristic in heat-affected zone
US5951788A (en) Superconducting high strength stainless steel magnetic component
JP3520633B2 (en) Maraging steel for hot tools with excellent toughness and high temperature strength

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 19950802

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE FR GB

17Q First examination report despatched

Effective date: 19960812

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 19961223