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WO2002066696A1 - Alliage de magnesium a haute resistance - Google Patents

Alliage de magnesium a haute resistance Download PDF

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Publication number
WO2002066696A1
WO2002066696A1 PCT/JP2001/000533 JP0100533W WO02066696A1 WO 2002066696 A1 WO2002066696 A1 WO 2002066696A1 JP 0100533 W JP0100533 W JP 0100533W WO 02066696 A1 WO02066696 A1 WO 02066696A1
Authority
WO
WIPO (PCT)
Prior art keywords
magnesium alloy
alloy
ductility
strength magnesium
hardness
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
Application number
PCT/JP2001/000533
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English (en)
Japanese (ja)
Inventor
Yoshihito Kawamura
Akihisa Inoue
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.)
Tohoku Techno Arch Co Ltd
Original Assignee
Tohoku Techno Arch Co Ltd
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 Tohoku Techno Arch Co Ltd filed Critical Tohoku Techno Arch Co Ltd
Priority to PCT/JP2001/000533 priority Critical patent/WO2002066696A1/fr
Priority to JP2002566397A priority patent/JP5161414B2/ja
Publication of WO2002066696A1 publication Critical patent/WO2002066696A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C23/00—Alloys based on magnesium
    • C22C23/06—Alloys based on magnesium with a rare earth metal as the next major constituent
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C23/00—Alloys based on magnesium
    • C22C23/04—Alloys based on magnesium with zinc or cadmium as the next major constituent
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
    • C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
    • C22F1/06—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of magnesium or alloys based thereon

Definitions

  • the present invention relates to a magnesium alloy, and particularly to a high-strength magnesium alloy having a fine crystal structure.
  • Magnesium alloys are attracting attention as lightweight, high-strength materials because of their excellent specific strength and specific stiffness in addition to their lightweight properties.Magnesium alloys are materials that are expected to further improve their properties in the future. is there.
  • An object of the present invention is to provide a high-strength magnesium alloy having excellent tensile strength and good ductility.
  • the present invention provides a compound represented by the general formula: Mg (100-xy) Y ⁇ Zny ( ⁇ ⁇ 5, 0.3 ⁇ y ⁇ 6: where ⁇ and y are each 0 /.)
  • a high-strength magnesium alloy having the following composition and a fine crystal structure of 1 micrometer or less.
  • the present invention has a Mg 2 4 Y 5 and Upushironzetaita, others are Hep- Mg, respectively is also a high strength Maguneshiumu alloy and having the following microcrystalline structure 1 micrometer.
  • FIG. 1 is a diagram showing hardness and ductility of a rapidly solidified ribbon of a ternary Mg—Zn—Y ternary ribbon in a rapidly solidified state.
  • Figure 2 shows the hardness and ductility of the Mg-Zn-Y ternary rapidly solidified ribbon in the heat-treated state at 573 K.
  • Fig. 3 shows the hardness and ductility of the Mg-Zn-Y ternary rapidly solidified ribbon in the heat-treated state at 673K.
  • FIG. 4 is a diagram showing a system for producing a rapidly solidified powder and a production of an extruded billet by a gas-to-tomizing method.
  • FIG. 5 is a diagram showing a process of heating and pressing a billet to perform solidification molding.
  • FIG. 6 is a graph showing tensile yield strength and elongation for alloys extruded at various temperatures.
  • FIG. 7 is a diagram showing a spectrum by X-ray diffraction.
  • Figure 8 shows the tensile yield strength and the tensile strength at various ambient temperatures for the extruded alloy. 4 is a graph showing extension.
  • FIG. 9 is a graph showing that the extruded alloy has superplasticity.
  • FIG. 10 is a view showing a photograph of an extruded alloy by an electron microscope.
  • FIG. 11 is a diagram showing a comparison between the tensile yield strength and the elongation of the magnesium alloy of the present invention and another magnesium alloy.
  • alloy composition exploration performed using the Mg—Zn—Y rapidly solidified ribbon was performed, and based on the results of these series of composition exploration, the Mg—Zn—YRS PZM material was subjected to gas atomization.
  • a magnesium alloy master alloy for composition exploration was prepared in an Ar atmosphere using a high-frequency melting furnace.
  • the rapid quasi-solid strip used for the exploration of the alloy composition was prepared by a single roll liquid quenching method.
  • the obtained rapidly solidified ribbon was subjected to a heat treatment at 573 K and 673 K assuming solidification molding (extrusion molding) in the RSP / M method, thereby producing a heat-treated material.
  • the structures of the rapidly solidified material and the heat-treated material were examined by X-ray diffraction.
  • mechanical properties such as tensile strength and hardness were examined using an Instron tensile tester and a Micro Vickers hardness tester. Ductility was evaluated by a 180 ° contact bending test.
  • the results of the synthetic composition survey will be described with reference to FIGS. 1 to 3 of the drawings. In the following description, the composition of the alloy is shown in atomic%.
  • Figures 1 to 3 show the hardness and ductility of the Mg-Zn-Y rapidly solidified ribbon before heat treatment and after heat treatment at 573 K and 6773 K, respectively. Shown for These temperatures are the lower limit (5 7 3 3) and the upper limit (6 7 3 K).
  • white circles indicate those that do not break even when bent 180 degrees and have high ductility. Those that break near 180 degrees are shown as brittle black circles.
  • the semi-black circle indicates that the ductile material showed good ductility such that it broke when bent at 180 degrees, but did not break even when bent to near 180 degrees.
  • the numbers below each circle indicate the diamond's pyramid hardness number (Vickers hardness).
  • the Mg-Zn-Y alloy was found to exhibit good ductility, high resilience, and hardness after heat treatment.
  • Mg went up solidifying and molding - Zn- Y alloy, in FIG. 2 and FIG. 3, Mg showed good ductility and high hardness - a Zn- Y alloy, Mg 9 7 Zn x Y 2 Alloy ( The test was performed using a material having the composition shown in (2) in Fig. 2 and Fig. 3.
  • FIGS. 4 and 5 A closed PM processing system was used to produce the rapidly solidified powder and solidify it.
  • the system used for the fabrication is shown in FIGS. 4 and 5.
  • Fig. 4 shows the process of producing a rapidly solidified powder by the gas atomization method and solidifying and forming a billet from the produced powder.
  • Fig. 5 shows the process before extruding the prepared billet. Using Fig. 4 and Fig. 5, the production and solidification molding of the rapidly solidified powder will be described in detail.
  • a powder of an Mg—Zn—Y alloy having a desired component ratio is prepared using a high-pressure gas atomizer 100.
  • an alloy having a target component ratio is melted by an induction coil 114 in a crucible 116 in a melting chamber 110.
  • the molten alloy is ejected by raising the stopper 112, and a high-pressure inert gas (for example, helium gas or argon gas) is sprayed from the nozzle 132 to spray the alloy, thereby producing an alloy powder.
  • a high-pressure inert gas for example, helium gas or argon gas
  • the nozzles and the like are heated by the heater 131.
  • the atomizing chamber 130 is monitored by an oxygen analyzer 162 and a vacuum gauge 164.
  • the produced alloy powder is collected through a cyclone classifier 140 in a hopper 220 in a vacuum glove / bottom 200. Subsequent processing is performed in this vacuum glove 'box 200. Next, the powder having the desired fineness is obtained by gradually passing through a fine sieve 230 in a vacuum glove box 200. In the present invention, a powder having a particle size of 32 ⁇ or less is obtained.
  • precompression is performed using a vacuum hot press machine 240.
  • a vacuum hot press machine capable of performing a 30-ton press was used.
  • the alloy powder is filled into a copper can 254 using a hot press machine 240, and a cap 252 is covered from above.
  • the cap 252 and the can 2554 are welded by the welding machine 256 while rotating with the turntable 258 to produce a billet 260.
  • the billet 260 is checked for leakage by connecting to a vacuum pump via the valve 262. If there is no leak, close the pulp 262 and remove the alloy bilette 260 from the entrance box 280 of the vacuum glove box 202 with the valve 262 still attached. As shown in FIG. 5, the billet 260 taken out is connected to a vacuum pump and degassed while being heated and preheated.
  • the cap of the billet 260 is squeezed and then spot-welded with a spot welder 340 to cut off the connection between the billet 260 and the outside (see Fig. 5 (b)).
  • the billet of the alloy together with the container is put into an extruder 400 to form a final shape (see FIG. 5 (c)).
  • the extrusion press machine has a performance of 100 tons for the main 'press (main' stem 450 side), and a performance of 20 tons for the back press (back stem 470 side).
  • the extrusion temperature can be set.
  • the rapidly solidified powder of the present invention was produced by the high-pressure He gas atomizing method.
  • the prepared powder having a particle size of 32 zm or less is filled in a copper can, and then filled in a vacuum to produce a billet.
  • the extrusion exerts pressure and shear on the powder, achieving densification and bonding between the powders. It should be noted that shearing occurs even in forming by rolling or forging.
  • the structures of the rapidly solidified powder and extruded material were examined by X-ray diffraction and ⁇ observation. Tensile tests were performed at an initial strain rate 5 X 10- 4 s 1 using an Instron tensile tester.
  • Mg 9 7 Zn x Y 2 material tensile yield strength was produced by extruding at various temperatures in Fig. 6 (0.2% ⁇ Ka) shows the elongation.
  • the horizontal axis in FIG. 6 indicates the temperature of extrusion molding.
  • Figure 7 shows the results of the X-ray spectrum diffraction.
  • the Figure 8 shows the tensile yield strength and elongation (extruded at 573 K) Mg 9 7 Zn Y 2 at various ambient temperatures.
  • FIG. 9 shows the elongation and stress to strain ratio of Mg 9 7 Zn 1 Y 2 material at ambient temperature 623 ⁇ (573 ⁇ , extruded at an extrusion ratio of 10).
  • Mg 9 7 Z ni Y 2 it can be seen that the yield strength and elongation of the RS Rozetamyu material is dependent on the extrusion temperature. The reason why the tensile yield strength decreases as the extrusion temperature increases is that the crystal grain size increases. However, Mg 9 7 Z ni Y 2 RS ⁇ / ⁇ material, in any of the extrusion temperature, showed high yield strength of at least 40 OMP a. In particular, was it made at an extrusion temperature of 573? The material exhibited a maximum yield strength of 625 MPa, a yield strength of 606 MPa, and an elongation of 5%, and was able to develop an RS PZM magnesium alloy having both high strength and high ductility.
  • Figure 7 shows the results of X-ray diffraction. As can be seen, in the spectrum of the powder produced by the gas atomization method (see Fig. 7 (a)), hep-Mg and YZn were detected, but the extruded alloy material ( Fig. 7 (b)- In (e) refer), all, hep- Mg, Mg 2 4 Y 5 and YZn is detected.
  • FIG. 8 shows the ambient temperature dependence of the tensile strength of a commercially available magnesium alloy (WE54-T6) and the magnesium alloy of the present invention. Fabricated Mg 9 7 Z n t Y 2 RS ⁇ material, a better tensile strength commercial magnesium alloys is shown at ambient temperature most.
  • Mg 9 7 Z n Y 2 RS P / M material is a magnesium alloy produced have shown that it has a superplastic.
  • “Superplasticity” means that the elongation exceeds 200% and the gradient of flow stress (m value) with respect to the strain rate is 0.3 or more, regardless of the ambient temperature and the strain rate. ing. Particularly superplastic appearing in IX 1 0 one 2 s-1 or more strain rate is said to fast superplasticity.
  • to give 1 X 1 0- 2 s- 1 or more indicates a more than 300% of Shinpi, elongation up to 75 ⁇ % at 5 X 1 CD- 3 s- 1 Have been.
  • the upper figure shows that the m value is 0.4, indicating that the produced magnesium alloy has high-speed superplasticity14.
  • the composition of the produced magnesium alloy is composed of fine particles of about 200 nm. These fine particles have a crystal structure as a molded product, not a crystal structure of a powder produced by gas atomization, and are a mixed phase of magnesium having a hexagonal close-packed structure (hep) and another compound.
  • Fig. 11 shows a comparison of elongation and tensile yield strength between the magnesium alloy manufactured by Hyoaki Honmei and the existing magnesium alloy.
  • the magnesium alloy (AZ91, ZK60, etc.) prepared by the existing IZM (ing ot metallurgy) method and the magnesium alloy (AZ91, ZK6) prepared by rapid solidification powder metallurgy (RS P / M) are shown. 1 etc.), Nano-crystal mags by rapid solidification powder metallurgy (RS P / M) with a composition other than the present invention
  • a comparison is made between a magnesium alloy and an RSP / M method magnesium alloy having a fine crystal structure having the composition of the present invention.
  • the magnesium alloy of the present invention has very good performance with respect to tensile yield strength and elongation as compared with magnesium alloys of other production methods and compositions.
  • Industrial Applicability The magnesium alloy of the present invention has high strength and high ductility.
  • 100 high pressure gas atomizer
  • 110 melting chamber
  • 112 stopper
  • 114 induction coil
  • 116 crucible
  • 130 atomizing chamber
  • 150 filter, 162, 166: oxygen analyzer, 164: vacuum gauge, 200: vacuum glove box, 210: argon gas refiner, 220: hopper, 230: sieve, 240: vacuum hot press machine,
  • 252 Cap, 254: Can, 256: Welder, 258: Rotating disk, 260: Billet, 262: Valve, 270: Oxidation box,

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Powder Metallurgy (AREA)
  • Manufacture Of Metal Powder And Suspensions Thereof (AREA)

Abstract

L'invention concerne un alliage de magnésium à haute résistance, qui se caractérise en ce qu'il a une composition représentée par la formule générale: Mg(100-x-y)YxZny, dans laquelle x et y représentent chacun un % atomique, et 1<x<5 et 0,3<y<6, et une structure microcristalline dont le diamètre de grain est au plus égal à 1νm. La figure jointe montre la dureté et la ténacité d'une bande mince de Mg-Zn-Y rapidement solidifiée après traitement thermique à 673K. Un cercle ouvert indique une bande mince présentant une ténacité élevée et exempte de rupture ou de fissure, même pliée à un angle de 180° et un cercle noir de la bande causant rupture et fissure. Le nombre apparaissant sous chaque cercle indique une valeur de dureté au diamant pyramidal (dureté Vickers). Les données expérimentales, y compris celles de la figure, indiquent clairement que l'alliage de magnésium à haute résistance présente non seulement une excellente résistance à la traction, mais également une bonne ténacité, c'est-à-dire une excellente propriété mécanique.
PCT/JP2001/000533 2001-01-26 2001-01-26 Alliage de magnesium a haute resistance Ceased WO2002066696A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
PCT/JP2001/000533 WO2002066696A1 (fr) 2001-01-26 2001-01-26 Alliage de magnesium a haute resistance
JP2002566397A JP5161414B2 (ja) 2001-01-26 2001-01-26 高強度マグネシウム合金

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2001/000533 WO2002066696A1 (fr) 2001-01-26 2001-01-26 Alliage de magnesium a haute resistance

Publications (1)

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WO2002066696A1 true WO2002066696A1 (fr) 2002-08-29

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005052203A1 (fr) 2003-11-26 2005-06-09 Yoshihito Kawamura Alliage de magnesium haute resistance et haute tenacite et son procede de production
WO2006036033A1 (fr) * 2004-09-30 2006-04-06 Yoshihito Kawamura Métal de grande dureté et de résistance élevée and procédé de fabrication dudit métal
JP2009144215A (ja) * 2007-12-17 2009-07-02 Japan Steel Works Ltd:The 耐熱マグネシウム合金材およびその製造方法
CN107761022A (zh) * 2017-09-28 2018-03-06 青海大学 一种混合相增强镁基复合材料及其制备方法
CN109852857A (zh) * 2019-03-29 2019-06-07 上海交通大学 适于重力铸造的高强韧耐热Mg-Y合金及其制备方法
CN109868402A (zh) * 2019-03-29 2019-06-11 上海交通大学 高强韧耐热压铸Mg-Y合金及其制备方法

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1989011552A1 (fr) * 1988-05-23 1989-11-30 Allied-Signal Inc. Formage superplastique d'alliages metalliques a base de magnesium solidifies rapidement
JPH05306424A (ja) * 1992-04-30 1993-11-19 Yoshida Kogyo Kk <Ykk> 高強度マグネシウム基合金およびその集成固化材
US5348591A (en) * 1991-09-06 1994-09-20 Tsuyoshi Masumoto High-strength amorphous magnesium alloy
JPH073375A (ja) * 1993-03-15 1995-01-06 Takeshi Masumoto 高強度マグネシウム合金及びその製造方法

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2511526B2 (ja) * 1989-07-13 1996-06-26 ワイケイケイ株式会社 高力マグネシウム基合金

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1989011552A1 (fr) * 1988-05-23 1989-11-30 Allied-Signal Inc. Formage superplastique d'alliages metalliques a base de magnesium solidifies rapidement
US5348591A (en) * 1991-09-06 1994-09-20 Tsuyoshi Masumoto High-strength amorphous magnesium alloy
JPH05306424A (ja) * 1992-04-30 1993-11-19 Yoshida Kogyo Kk <Ykk> 高強度マグネシウム基合金およびその集成固化材
JPH073375A (ja) * 1993-03-15 1995-01-06 Takeshi Masumoto 高強度マグネシウム合金及びその製造方法

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005052203A1 (fr) 2003-11-26 2005-06-09 Yoshihito Kawamura Alliage de magnesium haute resistance et haute tenacite et son procede de production
EP1688509A4 (fr) * 2003-11-26 2008-07-09 Yoshihito Kawamura Alliage de magnesium haute resistance et haute tenacite et son procede de production
EP1690954A4 (fr) * 2003-11-26 2008-07-09 Yoshihito Kawamura Alliage de magnesium haute resistance et haute tenacite et son procede de production
US10184165B2 (en) 2003-11-26 2019-01-22 Yoshihito Kawamura High strength and high toughness magnesium alloy and method of producing the same
WO2006036033A1 (fr) * 2004-09-30 2006-04-06 Yoshihito Kawamura Métal de grande dureté et de résistance élevée and procédé de fabrication dudit métal
JP2009144215A (ja) * 2007-12-17 2009-07-02 Japan Steel Works Ltd:The 耐熱マグネシウム合金材およびその製造方法
CN107761022A (zh) * 2017-09-28 2018-03-06 青海大学 一种混合相增强镁基复合材料及其制备方法
CN107761022B (zh) * 2017-09-28 2020-03-20 青海大学 一种混合相增强镁基复合材料及其制备方法
CN109852857A (zh) * 2019-03-29 2019-06-07 上海交通大学 适于重力铸造的高强韧耐热Mg-Y合金及其制备方法
CN109868402A (zh) * 2019-03-29 2019-06-11 上海交通大学 高强韧耐热压铸Mg-Y合金及其制备方法
CN109852857B (zh) * 2019-03-29 2021-08-06 上海交通大学 适于重力铸造的高强韧耐热Mg-Y合金及其制备方法
CN109868402B (zh) * 2019-03-29 2021-08-17 上海交通大学 高强韧耐热压铸Mg-Y合金及其制备方法

Also Published As

Publication number Publication date
JPWO2002066696A1 (ja) 2004-06-24
JP5161414B2 (ja) 2013-03-13

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