WO1992009711A1 - Procede de preparation d'alliages eutectiques ou hyper-eutectiques et composites bases sur ces alliages - Google Patents

Procede de preparation d'alliages eutectiques ou hyper-eutectiques et composites bases sur ces alliages Download PDF

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Publication number
WO1992009711A1
WO1992009711A1 PCT/CA1991/000418 CA9100418W WO9209711A1 WO 1992009711 A1 WO1992009711 A1 WO 1992009711A1 CA 9100418 W CA9100418 W CA 9100418W WO 9209711 A1 WO9209711 A1 WO 9209711A1
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WO
WIPO (PCT)
Prior art keywords
alloy
particles
eutectic
refractory
metal
Prior art date
Application number
PCT/CA1991/000418
Other languages
English (en)
Inventor
David James Lloyd
Iljoon Jin
Original Assignee
Alcan International Limited
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
Priority claimed from CA002030928A external-priority patent/CA2030928A1/fr
Application filed by Alcan International Limited filed Critical Alcan International Limited
Priority to EP91920402A priority Critical patent/EP0559694B1/fr
Priority to DE69130227T priority patent/DE69130227T2/de
Priority to JP50021892A priority patent/JP3492681B2/ja
Publication of WO1992009711A1 publication Critical patent/WO1992009711A1/fr

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C1/00—Making non-ferrous alloys
    • C22C1/10—Alloys containing non-metals
    • C22C1/1036—Alloys containing non-metals starting from a melt
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C32/00—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ

Definitions

  • This invention relates to a method of preparing 5 improved eutectic and hyper-eutectic alloys and metal matrix composites containing such alloys.
  • Metal matrix composite materials have gained increasing acceptance as structural materials.
  • Such 0 composites typically are composed of reinforcing particles, such as fibres, grit, powder or the like that are embedded within a metallic matrix.
  • the reinforcement imparts strength, stiffness and other desirable properties to the composite, while the matrix protects the fibres and 5 transfers load within the composite.
  • the two components, matrix and reinforcement thus cooperate to achieve results which are improved over what either could provide on its own.
  • a typical composite is an aluminum alloy reinforced with particles of silicon carbide or alumina. 0
  • a major difficulty in the production of good quality metal matrix composites is segregation of the reinforcing particles. The segregation of particles occurs in the liquid state as well as during solidification. The segregation in the liquid state can be overcome by a 5 proper mixing of the liquid.
  • the reinforcing particles can be rejected ahead of the 0 solidification interface, and may agglomerate in the interdendritic liquid which solidifies last.
  • the reinforcing particles are not found inside the aluminum dendrites and, in this sense, it can be said that the aluminum dendrites do not ⁇ wet" the reinforcing particles. This results in a highly inho ogeneous distribution of reinforcing particles in the as-cast materials.
  • reinforcement particles are pushed by the solidification interface or are engulfed is primarily dependent upon the degree of wetting between the particles and the solid surface. If the solid, surface wets the particles, they are engulfed by the solid surface. In this case the particle distribution in the solidified material is as uniform as it was in the liquid state. On the other hand, if the solid surface, e.g. aluminum dendrite surface, does not wet the particles, they are pushed away, resulting in interdendritic segregation.
  • intermetallic compounds may precipitate directly from a melt of the alloy. These intermetallic compounds often tend to be coarse, brittle particles, and these particles tend to segregate due to density difference, particularly when the solidification rate is slow.
  • non-metallic refractory particles when added to a molten eutectic or hyper-eutectic alloy can be "wetted" or engulfed during solidification by causing at least one intermetallic phase to solidify first from the molten alloy during solidification thereof such that the refractory particles are wetted and engulfed by the intermetallic phase as it grows during solidification. Because the intermetallics wet and engulf the refractory particles, there is no longer a tendency for the refractory particles to segregate to the interdendritic regions and they remain homogeneously distributed throughout an as-solidified ingot.
  • the refractory particles act as a refiner for precipitating intermetallics.
  • the use of unreinforced hyper-eutectic alloys is very restricted because they often form coarse, brittle inter-metallic particles on solidification, and the intermetallic particles tend to segregate due to the density difference, particularly when the solidification rate is not rapid.
  • phosphorus additions and fluxing have previously been required to refine the primary silicon to a size suitable for good wear properties.
  • the efficiency of phosphorus to refine primary silicon decreases with increasing holding time of the melt, complicating the casting practice.
  • refractory particles such as silicon carbide particles
  • the addition of refractory particles, such as silicon carbide particles, according to the present invention can nucleate and refine these intermetallics, as well as modify their morphology, so that the deleterious effect of coarse intermetallics is reduced. This is of particular value for alloys that are intended for high temperature use.
  • the alloy composites of this invention in which the refractory particles act as a refiner for precipitating intermetallics have superior high temperature strength, making them useful for applications such as cast brake rotors.
  • the refractory particles may also serve as reinforcing particles in a composite with the eutectic or hyper-eutectic alloy. Thus, they may be used not only to refine a eutectic or hyper-eutectic alloy, but also to form a composite therewith.
  • the particles When the particles are used solely to refine an alloy, they are typically used in very small, e.g. sub- micron, sizes. On the other hand, when they are used also for reinforcing the alloy, they may be used in much larger sizes, e.g. up to 20 microns. For reinforcing, they are typically used in sizes in the range of 5-20 microns and preferably 10-15 microns. When the particles are used in reinforcing sizes, the wetting and engulf-ment of them by the intermetallic phase prevent the problem of segregating to the interdendritic regions during cooling.
  • the eutectic or hyper-eutectic alloy is an aluminum alloy, although other materials such as magnesium alloys can also be used.
  • the non-metallic refractory material is preferably a metal oxide, metal nitride, metal carbide or metal suicide.
  • the most preferred refractory material is silicon carbide or aluminum oxide particulate.
  • the invention also relates to new aluminum alloy products having improved high temperature properties.
  • One of the novel products is a particle reinforced aluminum alloy casting in which non-metallic refractory reinforcing particles are uniformly dispersed by being wetted by intermetallics formed during solidification.
  • Another novel product is a refined aluminum alloy casting in which intermetallics formed during solidification are uniformly dispersed as fine particles because of the refining effect of particles of non-metallic refractory material contained in the alloy.
  • the alloy of the novel products is an eutectic or hyper-eutectic aluminum alloy containing silicon, mag ⁇ nesium and manganese, preferably in the amounts 7-16 wt% silicon, 0.3-2.0 wt% magnesium and 0.5-3.0 wt% manganese.
  • the silicon assists fluidity and stabilizes the refractory particles; below 7% silicon the refractory material tends to be unstable while above 16% coarse intermetallics are formed and the composite becomes embrittled.
  • the magnesium improves wetting and provides strengthening; below 0.3% magnesium the wetting is poor, while above 2% there is shrinkage porosity.
  • the manganese forms intermetallics providing uniform refractory particle distribution and improved high temperature strength; below 0.5% manganese there is no improvement in high temperature strength and above 3.0% the casting temperature becomes too high.
  • the alloy also preferably contains up to 5.0 wt% copper. This improves elevated temperature strength with amounts above 5.0% providing poor casting fluidity and embrittlement.
  • Another optional component is nickel which may also be present in amounts up to 5.0 wt%. It also improves elevated temperature strength, although amounts above 5.0% cause coarse intermetallics and embrittlement.
  • a further common optional element is iron which may be present in amounts up to 1.0 wt%. At amounts above 1.0 wt% there is the danger of forming coarse intermetallics which cannot be refined by the refractory particles.
  • the alloy may also contain up to 0.2 wt%, preferably 0.1-0.2 wt%, titanium as a grain refiner.
  • Alloys of particular interest for high temperature applications are those containing substantial amounts of Mn.
  • Such alloys may be produced by adding Mn to traditional high temperature alloy compositions until the eutectic or hypereutectic range is reached. This is mixed with refractory particles, e.g. which refine the intermetallics and distribute the particles uniformly • throughout the matrix.
  • intermetallic While a typical intermetallic is a compound formed of at least two metallic components, within the process of this invention, silicon behaves in the manner of an intermetallic in its ability to wet and engulf refractory particles. Accordingly, the term "intermetallic" as used in this invention includes silicon.
  • Figure 1 is a photomicrograph of an A-356 alloy casting with refractory particles
  • Figures 2-7 are photomicrographs of hyper-eutectic castings with refractory particles according to the invention
  • Figure 8 is a photomicrograph of a hyper-eutectic alloy casting without refractory particles
  • Figure 9 is a photomicrograph of a hyper-eutectic alloy casting with refractory particles
  • Figure 10 is a photomicrograph of a further hyper- eutectic alloy casting without refractory particles
  • Figure 11 is a photomicrograph of a casting of the alloy of Fig. 10 with refractory particles
  • Figure 12 is bar graphs showing yield strengths of different matrix alloys and composites of the invention.
  • Figures 13-15 are plots of stress as a function of soak time for three different cast composites of the invention.
  • Example 1
  • An aluminum matrix composite was prepared by mixing 15% by volume of silicon carbide particles having sizes in the range of 10-15 ⁇ m with a melt of A356 aluminum alloy containing 6.5 to 7.5% Si and 0.3 to 0.45% Mg. This was cast and solidified to form an ingot having the microstructure shown in Figure 1. It will be seen that the reinforcing particles have been pushed ahead of the solidification interface and are not uniformly dispersed throughout the ingot.
  • Example 2
  • Example 3 Two melts were prepared by heating aluminum containing
  • Example 8 shows the microstructure of the ingot without the refractory particles, while Figure 9 shows the microstructure of the ingot with the refractory particles. The refinement of the silicon is clearly evident.
  • Example 4 shows the microstructure of the ingot without the refractory particles, while Figure 9 shows the microstructure of the ingot with the refractory particles. The refinement of the silicon is clearly evident.
  • a series of particle engulfment tests were carried out using alumina as the particulate.
  • Example 2 To illustrate the effectiveness of the refinement according to this invention, the procedure of Example 2 was repeated using a melt of Al - 7% Si - 2% Mn alloy. One cast ingot was made from the alloy itself and a second cast ingot was made from a composite of the alloy and 15% by volume of silicon carbide particles. Fig. 10 shows the microstructure of the cast alloy and Fig. 11 shows the microstructure of the cast composite. It can be seen that the primary Mn j Si ⁇ l ⁇ intermetallic dendrites in the cast alloy are completely refined by the SiC particles.
  • Example 7 Example 7
  • Three aluminum matrix composites were prepared by mixing 15% by volume of silicon carbide particles having sizes in the range of 10-15 ⁇ m with three different aluminum alloy melts.
  • the matrix alloys had the following compositions:
  • Alloy A Al - 10 wt% Si - 1.2 wt% Mn - 0.4 wt% Mg
  • Alloy B Al - 10 wt% Si - 1.2 wt% Mn - 0.4 wt% Mg - 5 wt% Ni
  • Alloy C Al - 10 wt% Si - 1.2 wt% Mn - 1.0 wt% Mg - 5 wt% Ni - 2.5 wt% Cu
  • the composites so formed were cast and solidified in the form of 12.7 mm diameter as-cast test bars and 57 mm diameter ingots.
  • the as-cast test bars were held for 100 hours at 250°C, and tensile tested at the soak temperature.
  • the 57 mm diameter ingots were extruded at 450°C to 9.5 mm diameter rod. Test bars were machined from the rod, and held at between 200 and 400°C for various times to examine the effect of long time exposure on the high temperature strength. The results are shown in Figure 12-15.
  • High temperature composite alloys may be used in casting applications, or as wrought products such as forgings and extrusions.
  • Figure 12 shows the strength retention of as-cast material after 100 hrs at 250°C, which is relevant for applications such as cast brake rotors. The figure shows that the new alloy composites have superior high temperature strength to the presently used A356-SiC composite. It is also apparent that adding SiC reinforcement to the unreinforced alloys adds to the high temperature performance of these materials.
  • additional softening mechanisms such as sub-structure and grain size coarsening, may operate which are usually absent in as-cast material.
  • Figures 13-15 show the time dependence of the softening at 250, 300 and 400°C. All 3 alloys show rapid softening in t h e first 10 hours of exposure, but beyond this are relatively stable. This initial softening is due to normal, precipitate coarsening n resolution, -wriiXe after this has occurred the alloys have excellent long term stability. Comparing the extrusion results with those for as-cast test bars in Figure 12, the extruded composites have somewhat superior strength. Industrial Applicability
  • the invention provides techniques for improving eutectic and hyper-eutectic alloys, which alloys can be used for the manufacture of a variety of industrial products by conventional techniques.

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  • 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)

Abstract

On décrit un procédé de préparation d'un alliage métallique eutectique ou hyper-eutectique raffiné ou renforcé et qui consiste à: faire fondre l'alliage métallique eutectique ou hyper-eutectique, ajouter des particules d'un matériau réfractaire non métallique à la matrice métallique fondue, mélanger l'alliage métallique fondu et les particules du máteriau réfractaire, et couler le mélange qui en résulte dans des conditions produisant la précipitation d'au moins une phase intermétallique de la matrice métallique fondue au cours de sa solidification, de sorte que les produits intermétalliques formés au cours de la solidification mouillent et englobent lesdites particules réfractaires. Les particules ajoutées peuvent être très petites et ne servir qu'à raffiner les produits intermétalliques de précipitation dans l'alliage, ou elles peuvent être plus grosses et servent de particules de renforcement dans un composite comprenant l'alliage. Les produits obtenus sont aussi nouveaux.
PCT/CA1991/000418 1990-11-27 1991-11-27 Procede de preparation d'alliages eutectiques ou hyper-eutectiques et composites bases sur ces alliages WO1992009711A1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
EP91920402A EP0559694B1 (fr) 1990-11-27 1991-11-27 Procede de preparation d'alliages ameliores hyper-eutectiques et composites bases sur ces alliages
DE69130227T DE69130227T2 (de) 1990-11-27 1991-11-27 Verfahren zur herstellung von verbesserte hypereutektische legierungen und auf diesen basierte verbundwerkstoffe
JP50021892A JP3492681B2 (ja) 1990-11-27 1991-11-27 改良された過共晶合金の製造方法およびこれを基本とする複合材料

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
CA002030928A CA2030928A1 (fr) 1990-11-27 1990-11-27 Materiaux composites ameliores a base d'alliages entectiques ou hyperentectiques et mode de fabrication connexes
CA2,030,928 1990-11-27
US77012491A 1991-10-02 1991-10-02
US770,124 1991-10-02

Publications (1)

Publication Number Publication Date
WO1992009711A1 true WO1992009711A1 (fr) 1992-06-11

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Country Link
EP (1) EP0559694B1 (fr)
JP (1) JP3492681B2 (fr)
DE (1) DE69130227T2 (fr)
WO (1) WO1992009711A1 (fr)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999006606A1 (fr) * 1997-07-28 1999-02-11 Alcan International Limited Materiau composite a matrice metallique coulee et son utilisation
GB2334966A (en) * 1998-03-05 1999-09-08 Aeromet International Plc An aluminium-copper alloy
EP1036849A2 (fr) * 1999-03-16 2000-09-20 Hitachi, Ltd. Matériau composite à matrice métallique, son procédé de préparation et son utilisation
US8540797B2 (en) 2008-07-29 2013-09-24 Indian Institute Of Science Process for preparation of nano ceramic-metal matrix composites and apparatus thereof
WO2014158384A1 (fr) * 2013-03-14 2014-10-02 Brunswick Corporation Alliage coulé en sable d'aluminium et de silicium hypereutectique contenant du nickel
US9650699B1 (en) 2013-03-14 2017-05-16 Brunswick Corporation Nickel containing hypereutectic aluminum-silicon sand cast alloys
US10370742B2 (en) 2013-03-14 2019-08-06 Brunswick Corporation Hypereutectic aluminum-silicon cast alloys having unique microstructure
CN114210987A (zh) * 2021-12-21 2022-03-22 上海交通大学 一种高体分颗粒增强钛基复合材料粉体及制备方法

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101787454B (zh) * 2010-04-12 2011-11-23 中国船舶重工集团公司第十二研究所 一种多组元增强铝基复合材料的制备方法
KR101964347B1 (ko) * 2017-11-06 2019-04-01 한국생산기술연구원 알루미늄 합금 다이캐스팅재 및 이의 제조방법

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3951651A (en) * 1972-08-07 1976-04-20 Massachusetts Institute Of Technology Metal composition and methods for preparing liquid-solid alloy metal compositions and for casting the metal compositions
US3993478A (en) * 1972-02-09 1976-11-23 Copper Range Company Process for dispersoid strengthening of copper by fusion metallurgy
GB2112813A (en) * 1981-12-25 1983-07-27 Nissan Motor Wear-resistant aluminum base composite material suitable for casting and method of preparing same

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3993478A (en) * 1972-02-09 1976-11-23 Copper Range Company Process for dispersoid strengthening of copper by fusion metallurgy
US3951651A (en) * 1972-08-07 1976-04-20 Massachusetts Institute Of Technology Metal composition and methods for preparing liquid-solid alloy metal compositions and for casting the metal compositions
GB2112813A (en) * 1981-12-25 1983-07-27 Nissan Motor Wear-resistant aluminum base composite material suitable for casting and method of preparing same

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6086688A (en) * 1997-07-28 2000-07-11 Alcan International Ltd. Cast metal-matrix composite material and its use
WO1999006606A1 (fr) * 1997-07-28 1999-02-11 Alcan International Limited Materiau composite a matrice metallique coulee et son utilisation
GB2334966B (en) * 1998-03-05 2003-03-05 Aeromet Internat Plc Cast aluminium-copper alloy
GB2334966A (en) * 1998-03-05 1999-09-08 Aeromet International Plc An aluminium-copper alloy
US6126898A (en) * 1998-03-05 2000-10-03 Aeromet International Plc Cast aluminium-copper alloy
US6630734B2 (en) 1999-03-16 2003-10-07 Hitachi, Ltd. Composite material, and manufacturing method and uses of same
EP1036849A3 (fr) * 1999-03-16 2002-09-25 Hitachi, Ltd. Matériau composite à matrice métallique, son procédé de préparation et son utilisation
US6611056B2 (en) 1999-03-16 2003-08-26 Hitachi, Ltd. Composite material, and manufacturing method and uses of same
EP1036849A2 (fr) * 1999-03-16 2000-09-20 Hitachi, Ltd. Matériau composite à matrice métallique, son procédé de préparation et son utilisation
US6646344B1 (en) 1999-03-16 2003-11-11 Hitachi, Ltd. Composite material, and manufacturing method and uses of same
US8540797B2 (en) 2008-07-29 2013-09-24 Indian Institute Of Science Process for preparation of nano ceramic-metal matrix composites and apparatus thereof
WO2014158384A1 (fr) * 2013-03-14 2014-10-02 Brunswick Corporation Alliage coulé en sable d'aluminium et de silicium hypereutectique contenant du nickel
CN105074027A (zh) * 2013-03-14 2015-11-18 布伦斯威克公司 含镍过共晶铝硅砂型铸造合金
US9650699B1 (en) 2013-03-14 2017-05-16 Brunswick Corporation Nickel containing hypereutectic aluminum-silicon sand cast alloys
US10370742B2 (en) 2013-03-14 2019-08-06 Brunswick Corporation Hypereutectic aluminum-silicon cast alloys having unique microstructure
CN114210987A (zh) * 2021-12-21 2022-03-22 上海交通大学 一种高体分颗粒增强钛基复合材料粉体及制备方法

Also Published As

Publication number Publication date
EP0559694A1 (fr) 1993-09-15
DE69130227T2 (de) 1999-01-21
JPH06502689A (ja) 1994-03-24
JP3492681B2 (ja) 2004-02-03
DE69130227D1 (de) 1998-10-22
EP0559694B1 (fr) 1998-09-16

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