US20090047171A1 - 6000-series aluminium extruded material superior in paint-baking hardenability and method for manufacturing the same - Google Patents

6000-series aluminium extruded material superior in paint-baking hardenability and method for manufacturing the same Download PDF

Info

Publication number
US20090047171A1
US20090047171A1 US12/093,009 US9300907A US2009047171A1 US 20090047171 A1 US20090047171 A1 US 20090047171A1 US 9300907 A US9300907 A US 9300907A US 2009047171 A1 US2009047171 A1 US 2009047171A1
Authority
US
United States
Prior art keywords
mass
less
mpa
extruded material
yield strength
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.)
Abandoned
Application number
US12/093,009
Other languages
English (en)
Inventor
Masamichi Aono
Toshitaka Miyaki
Tomoo Yoshida
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
Individual
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 Individual filed Critical Individual
Assigned to TOYOTA JIDOSHA KABUSHIKI KAISHA reassignment TOYOTA JIDOSHA KABUSHIKI KAISHA ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: AONO, MASAMICHI, MIYAKI, TOSHITAKA, YOSHIDA, TOMOO
Publication of US20090047171A1 publication Critical patent/US20090047171A1/en
Abandoned legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
    • B21C23/00—Extruding metal; Impact extrusion
    • B21C23/002—Extruding materials of special alloys so far as the composition of the alloy requires or permits special extruding methods of sequences
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C21/00—Alloys based on aluminium
    • C22C21/02—Alloys based on aluminium with silicon as the next major constituent
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C21/00—Alloys based on aluminium
    • C22C21/06—Alloys based on aluminium with magnesium 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
    • 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
    • C22F1/04—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of aluminium or alloys based thereon
    • C22F1/043—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of aluminium or alloys based thereon of alloys with silicon as the next major constituent

Definitions

  • the present invention relates to a 6000-series aluminium (Al—Mg—Si alloy) extruded material superior in paint-baking hardenability, which can be improved in terms of yield strength when subjected to a thermal history corresponding to paint baking as well as when subjected to thermal refining.
  • the present invention can be applied to members subjected to a thermal history corresponding to paint baking, such as structural members of vehicles (e.g., automobiles), including frame structural members such as a side sill, a side member, a cross member, and a door frame.
  • aluminium alloys used for structural members of automobiles and the like have been gaining attention from the viewpoint of global environmental protection.
  • prices per unit weight of aluminium are more expensive than those of steel.
  • component costs tend to become expensive while weight reduction can be achieved.
  • Structural members of automobiles and the like can be manufactured by the following manufacturing steps of: extrusion molding ⁇ stretch straightening ⁇ cutting (aluminium extrusion step); secondary processing involving bending (depending on types of structural members of automobiles and the like); and thermal refining ⁇ painting ⁇ paint baking.
  • extrusion molding ⁇ stretch straightening ⁇ cutting aluminium extrusion step
  • secondary processing involving bending depending on types of structural members of automobiles and the like
  • thermal refining ⁇ painting ⁇ paint baking During such steps of manufacturing structural members of automobiles and the like, an aluminium extruded material is subjected to two thermal histories corresponding to thermal refining and paint baking.
  • thermal refining when an aluminium extruded material in the state after secondary processing is treated by thermal refining, the load efficiency deteriorates, resulting in expensive product prices.
  • it is preferable to abolish thermal refining (if possible) or thermal refining upon secondary processing so
  • structural members of automobiles and the like have yield strengths at low levels upon secondary processing and the yield strengths of such structural members be secured to such an extent that the members are applicable when used as frame structural members such as a side sill, a side member, a cross member, and a door frame.
  • a 6000-series aluminium alloy which is an Al—Mg—Si alloy
  • so-called “negative effects” arise.
  • the yield strength of such alloy after natural aging increases compared with such strength immediately after extrusion, while the yield strength after aging treatment decreases compared with cases in which such alloy is not allowed to stand at room temperature.
  • the aluminium extruded profile having paint-baking hardenability does not experience yield strength increase even when allowed to stand at room temperature and efficiently exhibits performance after being subjected to a thermal history corresponding to paint baking.
  • JP Patent Publication (Kokai) No. 2004-204321 A discloses a method wherein working strain is introduced by stretch straightening, secondary processing, or the like following extrusion such that aging is accelerated.
  • JP Patent Publication (Kokai) No. 2002-235158 A discloses a method for producing an aluminum alloy extruded profile that is superior in bending workability and has paint-baking hardenability: wherein an aluminum alloy ingot containing Mg (0.3% to 1.3% by mass), Si (0.2% to 1.2% by mass), and Sn (0.01% to 0.3% by mass) with the balance comprising Al with inevitable impurities is preheated at 400 to 550° C. and subjected to hot extrusion molding, followed by cooling to 50° C. or less at a cooling rate of 50° C./min or more; and wherein the alloy is subjected to stabilizing treatment in the temperature range of 50 to 140° C. within 24 hours (hereafter abbreviated as “hr”) after the extrusion molding in a manner such that the alloy is retained for 0.5 to 50 hr while having a yield strength of 120 N/mm or less
  • aluminium extruded profile having paint-baking hardenability When an aluminium extruded profile having paint-baking hardenability is applied to structural members of automobiles and the like, it is preferable that such aluminium extruded profile have a yield strength of 180 MP or more in view of protection of vehicles upon crashing.
  • the present inventors have found that the above problems can be solved with the use of: an aluminium extruded material obtained by retaining a 6000-series aluminium alloy (Al—Mg—Si alloy) with a specific composition at a predetermined temperature for a predetermined period of time immediately after extrusion molding and allowing the alloy to be subjected to a thermal history corresponding to paint baking; or an aluminium extruded material obtained by setting a specific billet temperature and a specific cooling rate immediately after extrusion in the steps of manufacturing such extruded material with the use of the above 6000-series aluminium alloy. This has led to the completion of the present invention.
  • a 6000-series aluminium alloy Al—Mg—Si alloy
  • the present invention relates to a 6000-series aluminum extruded material containing: magnesium (0.3% to 0.7% by mass) and silicon (0.7% to 1.5% by mass) for the ensuring of strength; copper (0.35% or less by mass) for the ensuring of elongation; iron (0.35% or less by mass) for the ensuring of yield strength; titanium (0.005% to 0.1% by mass) for microcrystallization; and manganese (0.05% to 0.30% by mass), chrome (0.10% or less by mass), and zirconium (0.10% or less by mass) for tissue stabilization upon extrusion (provided that at least one transition element selected from the group consisting of manganese, chromium, and zirconium is contained in a total amount representing 0.05% to 0.40% by mass); with the balance comprising aluminum with inevitable impurities.
  • Such 6000-series aluminium extruded material has a predetermined yield strength of 180 MPa or more with an increase of 60 MPa as a result of a thermal history corresponding to paint baking.
  • the 6000-series aluminium extruded material of the present invention is an aluminium extruded material superior in paint-baking hardenability, which can be improved in terms of yield strength when subjected to a thermal history corresponding to paint baking as well as when subjected to thermal refining.
  • the 6000-series aluminium extruded material of the present invention can be obtained by the steps of:
  • the present invention relates to a method for manufacturing a 6000-series aluminium extruded material, wherein an aluminum alloy ingot containing magnesium (0.3% to 0.7% by mass), silicon (0.7% to 1.5% by mass), copper (0.35% or less by mass), iron (0.35% or less by mass), titanium (0.005% to 0.1% by mass), manganese (0.05% to 0.30% by mass), chrome (0.10% or less by mass), and zirconium (0.10% or less by mass) (provided that at least one transition element selected from the group consisting of manganese, chromium, and zirconium is contained in a total amount representing 0.05% to 0.40% by mass), with the balance comprising aluminum with inevitable impurities, is subjected to extrusion molding.
  • the 6000-series aluminium extruded material of the present invention can be obtained by the steps of:
  • a 6000-series extruded profile superior in paint-baking hardenability that has sufficient yield strength as a result of a thermal history corresponding to paint baking and a method for manufacturing the same are provided.
  • FIGS. 1A to 1C show steps of manufacturing automobile members with the use of conventional aluminium extruded profiles and the aluminium extruded profile of the present invention.
  • door frames were used as examples for comparison and explanation.
  • FIG. 1A shows steps of manufacturing a conventional separate-type door frame.
  • FIG. 1B shows steps of manufacturing a conventional integrated door frame.
  • FIG. 1C shows steps of manufacturing the integrated door frame of the present invention.
  • FIG. 2 shows a cross section of a test piece.
  • FIG. 3 shows a thermal history corresponding to paint baking.
  • FIGS. 1A to 1C show steps of manufacturing automobile members with the use of conventional aluminium extruded profiles and the aluminium extruded profile of the present invention.
  • door frames were used as examples for comparison and explanation.
  • FIG. 1A shows steps of manufacturing a conventional separate-type door frame.
  • a billet (BLT) consisting of an aluminium member is subjected to extrusion steps (extrusion molding ⁇ stretch straightening ⁇ cutting), bending such as stretch bending, secondary processing involving welding with another aluminium member, and thermal refining (e.g., T 5 (200° C. ⁇ 3 hr)) in that order.
  • extrusion steps extrusion molding ⁇ stretch straightening ⁇ cutting
  • bending such as stretch bending
  • secondary processing involving welding with another aluminium member e.g., T 5 (200° C. ⁇ 3 hr)
  • thermal refining e.g., T 5 (200° C. ⁇ 3 hr)
  • FIG. 1B shows steps of manufacturing a conventional integrated door frame.
  • a billet (BLT) consisting of an aluminium member is subjected to extrusion steps (extrusion molding ⁇ stretch straightening ⁇ cutting), secondary processing involving bending such as stretch bending, and thermal refining (e.g., T 5 (200° C. ⁇ 3 hr)) in that order.
  • extrusion steps extrusion molding ⁇ stretch straightening ⁇ cutting
  • secondary processing involving bending such as stretch bending
  • thermal refining e.g., T 5 (200° C. ⁇ 3 hr)
  • an aluminium extruded material is subjected to two different thermal histories corresponding to thermal refining and paint baking.
  • the load efficiency deteriorates, resulting in high product costs.
  • FIG. 1C shows steps of manufacturing the integrated door frame of the present invention.
  • a billet (BLT) consisting of an aluminium member is subjected to extrusion steps (extrusion molding ⁇ stretch straightening ⁇ cutting), and secondary processing involving bending such as stretch bending. Thereafter, a painting step is carried out without thermal refining and then the door frame is manufactured by paint baking at approximately 170° C. ⁇ 0.3 hr.
  • thermal refining is abolished such that the yield strength of an aluminium extruded material is increased with the use of a single thermal history corresponding to paint baking alone.
  • the aging temperature of paint baking is lower than that of general thermal refining (e.g., 200° C. ⁇ 3 hr).
  • the retention time for paint baking is shorter than that for general thermal refining.
  • the density of an Mg 2 Si precipitate that is deposited upon aging treatment is preferably equivalent to that obtained upon thermal refining, even in a case in which an aluminium extruded profile having paint-baking hardenability is treated at a low aging temperature and retained for a short period of time.
  • the yield strength of a 6000-series aluminium alloy can be improved with the presence of such Mg 2 Si precipitate. Therefore, although magnesium and silicon are contained in the case of the present invention, the upper limits of the magnesium and silicon contents are provided. This is because excessive magnesium and silicon contents can significantly inhibit extrusion moldability. Further, the presence of copper results in the improvement of yield strength and elongation. However, excessive copper content inhibits extrusion moldability and corrosion resistance. Furthermore, regarding iron, iron crystal is obtained upon casting and a bulky iron precipitate is deposited upon high-temperature heating, resulting in the decreased density of an Mg 2 Si precipitate that is deposited upon aging treatment. Accordingly, inhibition of the increase in yield strength occurs upon aging treatment.
  • an aluminium extruded profile having paint-baking hardenability and a method for manufacturing the same are established.
  • Such aluminium extruded profile satisfies the scope of alloy contents allowing paint-baking hardenability to be efficiently exhibited without the inhibition of extrusion moldability of 6000-series aluminium alloy, and the yield strength of such aluminium extruded profile can be secured at 180 MPa or more with an increase of 60 MPa as a result of a thermal history corresponding to paint baking in view of protection of vehicles upon crushing.
  • the magnesium content is preferably 0.3% or more.
  • the magnesium content is preferably 0.7% or less. Therefore, the magnesium content is 0.3% to 0.7% and more preferably 0.4% to 0.6%.
  • the silicon content is preferably 0.7% or more.
  • the silicon content is preferably 1.5% or less.
  • the silicon content is 0.7% to 1.5% and more preferably 0.8% to 1.3%.
  • copper is contained for the ensuring of strength and elongation.
  • excessive copper content causes a decrease in corrosion resistance.
  • deformation resistance upon extrusion increases so that productivity tends to be inhibited.
  • the copper content is 0.35% or less.
  • an intermetallic compound comprising iron is crystallized in a large amount, resulting in a decrease in alloy strength.
  • Such intermetallic compound is bulky and contains silicon that constitutes an Mg 2 Si precipitate which causes the improvement of yield strength upon subsequent aging treatment.
  • the density of the precipitate decreases.
  • excessive iron content causes a decrease in corrosion resistance.
  • the iron content is 0.35% or less.
  • Manganese, chrome, and zirconium have effects of inhibiting recrystallization upon extrusion and stabilizing the fibrous structure.
  • chrome and zirconium significantly inhibit quenching sensitivity.
  • a supersaturated solid solution is less likely to be formed during fan air cooling following extrusion in the case of an aluminium extruded profile that constitutes a structural member of automobiles and the like.
  • the density of an Mg 2 Si precipitate that causes the improvement of yield strength decreases.
  • zirconium is formed into an intermetallic compound with titanium upon casting, resulting in fewer effects of titanium microcrystallization and the occurrence of cracking upon casting.
  • Manganese is relatively less likely to inhibit quenching sensitivity and is likely to suppress recrystallization.
  • the manganese content In order to obtain recrystallization suppression effects, the manganese content must be 0.05% or more. However, when the manganese content is 0.30% or more, quenching sensitivity is inhibited, as with the cases of chrome and zirconium.
  • a supersaturated solid solution is less likely to be formed during fan air cooling following extrusion in the case of an aluminium extruded profile that constitutes a structural member of automobiles and the like. During a subsequent aging treatment, the density of an Mg 2 Si precipitate that causes the improvement of yield strength decreases.
  • the manganese content is 0.05% to 0.30%
  • the chrome content is 0.10% or less
  • the zirconium content is 0.10% or less.
  • the total content of at least one transition element selected from the group consisting of manganese, chrome, and zirconium is 0.05% to 0.40%.
  • the titanium content can be 0.005% to 0.10%, more preferably 0.005% to 0.05%, and further preferably 0.005% to 0.03%.
  • Incorporation of inevitable impurities occurs via different routes. Different elements are incorporated; however, they hardly influence alloy properties as long as the content of a single element is 0.05% or less and the total content of such elements is 0.15% or less. In view of the above, the content of a single inevitable impurity is 0.05% or less and the total content of inevitable impurities is 0.15% or less.
  • An aluminium extruded material having paint-baking hardenability refers to an aluminium extruded profile subjected to the manufacturing steps of: extrusion molding ⁇ retention at 90 ⁇ 50° C. ⁇ 1 to 24 hr; painting; and a thermal history corresponding to paint baking.
  • nuclei i.e., GPzones
  • Mg 2 Si precipitates
  • an aluminium extruded material having paint-baking hardenability be retained at 50° C. or more.
  • Mg 2 Si precipitates excessively grow, resulting in an increase in yield strength.
  • workability tends to be inhibited.
  • the temperature is preferably retained at 120° C. or less.
  • retention is carried out at 90 ⁇ 50° C. ⁇ 1 to 24 hr and preferably at 70 ⁇ 10° C. ⁇ 1 to 12 hr following extrusion molding.
  • Such retention step at 90 ⁇ 50° C. ⁇ 1 to 24 hr may be carried out in an atmosphere furnace, a water bath, or an oil bath following extrusion molding and air cooling.
  • such aluminium extruded material may be allowed to stand to cool at a controlled temperature following extrusion molding so as to be retained under thermal insulation.
  • the billet temperature is set at 500° C. or more and the cooling rate is set at not less than 70° C./min for 4 minutes immediately after extrusion during manufacturing.
  • such aluminium extruded material having paint-baking hardenability refers to an aluminium extruded profile retained at 90 ⁇ 50° C. ⁇ 1 to 24 hr immediately after extrusion molding and subjected to painting and a thermal history corresponding to paint baking.
  • the billet temperature In general extrusion steps, the billet temperature must be retained at 600° C. or less so that the upper limit of the temperature is not predetermined.
  • the billet heating temperature is set at 500° C.
  • the cooling rate is set at not less than 70° C./min for 4 minutes immediately after extrusion. Accordingly, a supersaturated solid solution, which is necessary for formation of nuclei (i.e., GPzones) of Mg 2 —Si precipitates that are formed as a result of subsequent retention at 90 ⁇ 50° C. ⁇ 1 to 24 hr, can be obtained.
  • the billet temperature is less than 500° C.
  • a vacancy that is necessary for GPzone formation cannot be formed inside an aluminium matrix.
  • the cooling rate is less than 70° C./min, a vacancy disappears during cooling, or solute atoms in a solid solution are deposited in the form of precipitates.
  • GPzones cannot be formed by subsequent retention at 90 ⁇ 50° C. ⁇ 1 to 24 hr.
  • the billet heating temperature is set at 500° C. or more and the cooling rate is set at not less than 70° C./min for 4 minutes immediately after extrusion.
  • nuclei i.e., GPzones
  • the cooling rate is set at not less than 70° C./min for 4 minutes immediately after extrusion.
  • nuclei i.e., GPzones
  • Mg 2 Si precipitates that are formed after retention at 90 ⁇ 50° C. ⁇ 1 to 24 hr
  • a greater number of GPzones can be formed by retention at low temperatures.
  • GPzone formation requires a retention time of 24 hr or more, resulting in the deterioration of production efficiency.
  • an aluminium extruded material having paint-baking hardenability is preferably retained at 50° C. or more.
  • Mg 2 Si precipitates grow excessively, resulting in an increase in yield strength.
  • workability tends to be inhibited.
  • the temperature is preferably retained at 120° C. or less.
  • retention is carried out at 90 ⁇ 50° C. ⁇ 1 to 24 hr and preferably at 70 ⁇ 10° C. ⁇ 1 to 12 hr following extrusion molding.
  • Such retention step at 90 ⁇ 50° C. ⁇ 1 to 24 hr may be carried out in an atmosphere furnace, a water bath, or an oil bath following extrusion molding and air cooling.
  • such aluminium extruded material may be allowed to stand to cool at a controlled temperature following extrusion molding so as to be retained under thermal insulation.
  • the aluminium extruded profile having paint-baking hardenability of the present invention is preferably used as a solid-core or hollow profile. It may be in a rectangular tube form, a cylindrical form, or an irregular form.
  • starting material contents were adjusted so as to achieve compositions of 6000-series aluminium alloys shown as test samples Nos. 1 and 2 listed in table 1.
  • the starting materials were dissolved and melted into cylindrical ingots (diameter: 204 mm ⁇ length: 700 mm) having a size appropriate for extrusion.
  • alloy contents listed in table 1 are expressed in analytical values. The value “0.00%” is shown for the effective digit.
  • ingots were subjected to homogenization treatment at 560° C. ⁇ 4 hr.
  • extrusion molding of ingots (billets) subjected to homogenization treatment was carried out using an extrusion molding die at predetermined extrusion temperatures (billet heating temperatures) under cooling conditions listed in table 2.
  • extrusion temperatures beam heating temperatures
  • aluminium extruded profiles each having a cross section of a frame structural member shown in FIG. 2 were formed.
  • the obtained aluminium extruded profiles having paint-baking hardenability were evaluated by tensile experiments regarding yield strength, strength, and breaking elongation.
  • Tensile properties were determined by collecting flat test pieces from the extruded profiles having paint-baking hardenability and examining the test pieces using a tensile tester (complying with the JIS standards) according to JIS-Z 2241.
  • a yield strength of 180 MPa or more was designated with “ ⁇ ” in view of protection of vehicles upon crushing.
  • a yield strength of 180 to 150 MPa was designated with “ ⁇ ,” because application is possible depending on sectional design.
  • a yield strength of less than 150 MPa was designated with “x.” Further, considering the cases involving secondary processing, differences in terms of yield strength before and after a thermal history corresponding paint baking of 60 MPa or more and of less than 60 MPa were designated with “ ⁇ ” and “x,” respectively. Then, comprehensive judgment was carried out. Table 3 shows the evaluation results.
  • Test sample No. 1 is an aluminium extruded profile containing Si (1.10%), Cu (0.20%), Mg (0.59%), and Mn (0.08%).
  • Test samples Nos. 1-1 to 1-3 corresponding to the Examples and a test sample No. 1-4 corresponding to the Comparative example were allowed to stand at room temperature for 12 to 168 hr following extrusion molding and retained at 70° C. ⁇ 12 hr. Then, the samples were compared in terms of yield strength before and after bake hardening (hereafter abbreviated as “B. H.”) treatment. In addition, test samples Nos.
  • test samples Nos. 1-1 to 1-4 corresponding to the Examples in the cases of the samples that had been allowed to stand at room temperature for less than 168 hr following extrusion molding (test samples Nos.
  • test samples Nos. 1-5 to 1-8 corresponding to the Examples were allowed to stand for 12 hr following extrusion molding, retained at 70° C. ⁇ 12 hr, and further allowed to stand at room temperature for 12 to 168 hr, followed by B. H. treatment.
  • Yield strengths after B. H. treatment were 214 MPa, 210 MPa, 209 MPa, and 212 MPa, respectively.
  • the samples were not affected as a result of being allowed to stand at room temperature after retention at 70° C. ⁇ 12 hr. Therefore, the results were all judged as corresponding to “ ⁇ .”
  • yield strength increases as a result of B. H. were 94 MPa, 92 MPa, 88 MPa, and 93 MPa, respectively.
  • Test sample No. 2 is an aluminium extruded profile containing Si (0.90%), Cu (0.20%), Mg (0.40%), and Mn (0.08%).
  • Test samples Nos. 2-1 to 2-3 corresponding to the Examples and test sample No. 2-4 corresponding to the Comparative example were allowed to stand at room temperature for 12 to 168 hr following extrusion molding and retained at 70° C. ⁇ 12 hr. Then, the samples were compared in terms of yield strength before and after B. H. treatment.
  • test samples Nos. 2-5 to 2-8 corresponding to the Examples were allowed to stand for 12 hr following extrusion molding, treated at 70° C. ⁇ 12 hr, and further allowed to stand at room temperature for 12 to 168 hr. Then, the samples were compared in terms of yield strength before and after B. H. treatment.
  • yield strength after B. H. treatment became lower in inverse proportion to the length of time during which the relevant sample was allowed to stand at room temperature following extrusion molding.
  • Yield strengths after B. H. treatment were 182 MPa, 176 MPa, 176 MPa, and 170 MPa, respectively.
  • the result was judged as corresponding to “ ⁇ ,” and in the cases of test samples Nos. 2-2 to 2-4, the results were judged as corresponding to “ ⁇ .”
  • yield strength increases as a result of B. H. were 92 MPa, 66 MPa, 60 MPa, and 35 MPa, respectively.
  • test sample No. 2-1 corresponding to the Example, which had been allowed to stand at room temperature for 12 hr following extrusion molding
  • the result was judged as corresponding to “ ⁇ .”
  • test samples No. 2-2 and 2-3 that had been allowed to stand at room temperature for 24 to 72 hr following extrusion molding
  • the results were judged as corresponding to “ ⁇ ” because application is possible depending on sectional design although low yield strengths were exhibited after B. H. treatment.
  • test sample No. 2-4 the result was judged as corresponding to “x.”
  • test samples No. 2-5 to 2-8 corresponding to the Examples were allowed to stand for 12 hr following extrusion molding, retained at 70° C. ⁇ 12 hr, and further allowed to stand at room temperature for 12 to 168 hr, followed by B. H. treatment.
  • Yield strengths after B. H. treatment were 184 MPa, 183 MPa, 181 MPa, and 185 MPa, respectively.
  • the samples were not affected as a result of being allowed to stand at room temperature after retention at 70° C. ⁇ 12 hr. Therefore, the results were all judged as corresponding to “ ⁇ .”
  • yield strength increases as a result of B. H. were 89 MPa, 87 MPa, 87 MPa, and 92 MPa, respectively.
  • the samples were not affected by as a result of being allowed to stand at room temperature after retention at 70° C. ⁇ 12 hr. Therefore, the results were all judged as corresponding to “ ⁇ .” Accordingly, in the cases of test samples No. 2-5 to 2-8 corresponding to the Examples, the results were all judged as corresponding to “ ⁇ ” upon comprehensive judgment.
  • starting material contents were adjusted so as to achieve the compositions of 6000-series aluminium alloys shown in table 4 (test samples Nos. 1 to 4).
  • the starting materials were dissolved and melted into cylindrical ingots (diameter: 204 mm ⁇ length: 700 mm) having a size appropriate for extrusion.
  • alloy contents listed in table 4 are expressed in analytical values. The value “0.00%” is shown for the effective digit.
  • the ingots were subjected to a homogenization treatment at 560° C. ⁇ 4 hr.
  • extrusion molding of ingots (billets) subjected to a homogenization treatment was carried out using an extrusion molding die at predetermined billet heating temperatures under cooling conditions listed in table 5.
  • aluminium extruded profiles each having a cross section of a frame structural member shown in FIG. 2 were formed.
  • a 45-cm fan was set to rotate at 1680 rpm.
  • the aluminium extruded material was retained at 70° C. ⁇ 12 hr, allowed to stand at room temperature for 1 week, and subjected to a thermal history (B. H. treatment) corresponding to paint baking shown in FIG. 2 .
  • a thermal history B. H. treatment
  • heat treatment corresponding to general thermal refining was not carried out.
  • the obtained aluminium extruded profiles having paint-baking hardenability were evaluated by tensile experiments regarding yield strength, strength, and breaking elongation.
  • Tensile properties were determined by collecting flat test pieces from the extruded profiles having paint-baking hardenability and examining the test pieces using a tensile tester (complying with the JIS standards) according to JIS-Z 2241 .
  • a yield strength of 180 MPa or more was designated with “ ⁇ ” in view of protection of vehicles upon crushing.
  • a yield strength of 180 to 150 MPa was designated with “ ⁇ ” because application is possible depending on sectional design.
  • Test sample No. 1 is an aluminium extruded profile containing Si (1.10%), Cu (0.20%), Mg (0.59%), and Mn (0.08%).
  • Test samples Nos. 1-1 to 1-4 were heated at different billet temperatures of 460° C., 480° C., 500° C., and 520° C., respectively, upon extrusion. The samples were compared in terms of yield strength before and after B. H. treatment.
  • a sample heated at a billet temperature of 500° C. upon extrusion and treated at a cooling rate of less than 70° C./min for 4 minutes immediately after extrusion was compared with the above samples.
  • test samples No. 1-1 and 1-2 In the cases of the samples treated at billet temperatures of less than 500° C. (test samples No. 1-1 and 1-2) and the sample treated at a cooling rate of less than 70° C./min for 4 minutes immediately after extrusion (test sample No. 1-5), the yield strength slightly increased as a result of B. H. Thus, the results were judged as corresponding to “x.” In the cases of the other samples, yield strength increases as a result of B. H. were 60 MPa or more, and thus the results were judged as corresponding to “ ⁇ .” Accordingly, upon comprehensive judgment of test sample No. 1, in the cases of the test samples (Nos. 1-3 and 1-4) corresponding to the Examples, which had been heated at billet temperatures of 500° C. or more, the results were judged as corresponding to “ ⁇ .” Also, in the cases of the other samples, the results were judged as corresponding to “x.”
  • Test sample No. 2 is an aluminium extruded profile containing Si (0.90%), Cu (0.20%), Mg (0.40%), and Mn (0.09%).
  • Test samples No. 2-1 to 2-4 were heated at different billet temperatures of 460° C., 480° C., 500° C., and 520° C., respectively, upon extrusion. The samples were compared in terms of yield strength before and after B. H. treatment. Further, a sample heated at billet temperature of 500° C. upon extrusion and treated at a cooling rate of less than 70° C./min for 4 minutes immediately after extrusion (test sample No. 2-5) was compared with the above samples. As a result, the yield strengths after B. H.
  • test samples No. 2-1 and 2-2 had low yield strengths after B. H. treatment, and thus the results were judged as corresponding to “x.”
  • the sample treated at a billet temperature of 500° C. (test sample 2-3) had a low but acceptable yield strength value of 150 MPa or more, and thus the result was judged as corresponding to “ ⁇ .”
  • the sample treated at a billet temperature of 520° C. (test sample No. 2-4) had a sufficiently high yield strength after B. H. treatment, and thus the result was judged as corresponding to “ ⁇ .”
  • test samples No. 2-1 were 52 MPa, 63 MPa, 85 MPa, 94 MPa, and 60 MPa, respectively.
  • the yield strength increase as a result of B. H. was less than 60 MPa, and thus the result was judged as corresponding to “x.”
  • yield strength increases as a result of B. H. were 60 MPa or more, and thus the results were judged as corresponding to “ ⁇ .” Accordingly, upon comprehensive judgment of test sample No. 2, in the cases of the samples (Nos.
  • Test sample No. 3 corresponding to the Comparative example 1 is an aluminium extruded profile containing Si (0.59%), Cu (0.20%), Mn (0.20%), Mg (0.60%), and Cr (0.02%).
  • the Si content does not fall within the scope of the present invention.
  • the material was subjected to extrusion at a billet temperature of 500° C. and a cooling rate of not less than 70° C./min for 4 minutes immediately after extrusion, followed by B. H. treatment without treatment at 70° C. ⁇ 2 h.
  • the yield strength was 105 MPa and the yield strength increase as a result of B. H.
  • Test sample No. 4 corresponding to the Comparative example is an aluminium extruded profile containing Si (0.44%) and Mg (0.49%).
  • the Si content does not fall within the scope of the present invention.
  • the material was subjected to extrusion at a billet temperature of 500° C. and a cooling rate of not less than 70° C./min for 4 minutes immediately after extrusion, followed by B. H. treatment without treatment at 70° C. ⁇ 2 h.
  • the yield strength was 85 MPa and the yield strength increase as a result of B. H. was 14 MPa, and thus the results were judged as corresponding to “x.”
  • the yield strength was 233 MPa.
  • the material can be applied depending on type of structural member used in automobiles and the like. However, such material might have poor paint-baking hardenability, resulting in cost increase.
  • the present invention it is possible to provide a 6000-series aluminium extruded profile superior in paint-baking hardenability, the yield strength of which can be secured to a level applicable to structural members of automobiles and the like with the use of a thermal history corresponding to paint baking.
  • the aluminium extruded profile of the present invention can be applied to members that are subjected to a thermal history corresponding to paint baking, such as structural members of vehicles (e.g., automobiles), including frame structural members such as a side sill, a side member, a cross member, and a door frame.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Extrusion Of Metal (AREA)
  • Body Structure For Vehicles (AREA)
US12/093,009 2006-03-30 2007-03-30 6000-series aluminium extruded material superior in paint-baking hardenability and method for manufacturing the same Abandoned US20090047171A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
JP2006-095881 2006-03-30
JP2006095881A JP5166702B2 (ja) 2006-03-30 2006-03-30 塗装焼付け硬化性に優れた６０００系アルミニウム押出材及びその製造方法
PCT/JP2007/057724 WO2007114521A1 (ja) 2006-03-30 2007-03-30 塗装焼付け硬化性に優れた６０００系アルミニウム押出材及びその製造方法

Publications (1)

Publication Number Publication Date
US20090047171A1 true US20090047171A1 (en) 2009-02-19

Family

ID=38563779

Family Applications (1)

Application Number Title Priority Date Filing Date
US12/093,009 Abandoned US20090047171A1 (en) 2006-03-30 2007-03-30 6000-series aluminium extruded material superior in paint-baking hardenability and method for manufacturing the same

Country Status (6)

Country Link
US (1) US20090047171A1 (zh)
EP (1) EP2006404A4 (zh)
JP (1) JP5166702B2 (zh)
CN (1) CN101356294A (zh)
CA (1) CA2628229A1 (zh)
WO (1) WO2007114521A1 (zh)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102912198B (zh) * 2012-11-09 2015-01-07 虞海香 一种抑制大晶粒形成的铝合金加工方法
JP6005544B2 (ja) * 2013-02-13 2016-10-12 株式会社神戸製鋼所 焼付け塗装硬化性に優れたアルミニウム合金板
CN104561681A (zh) * 2014-12-22 2015-04-29 河南明泰铝业股份有限公司 汽车车身用6016铝合金薄板及其生产方法
CN112626385B (zh) * 2020-11-04 2022-08-16 佛山科学技术学院 一种高塑性快速时效响应的铝合金及其制备方法和应用

Family Cites Families (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5528387A (en) * 1979-05-29 1980-02-28 Nikkei Riken Kk Aluminum alloy die material and production thereof
JPS58167757A (ja) * 1982-03-29 1983-10-04 Nippon Light Metal Co Ltd 耐食性，溶接性および焼入性のすぐれた加工用Ａｌ−Ｍｇ−Ｓｉ系合金の製造法
JPS59215453A (ja) * 1983-05-23 1984-12-05 Furukawa Alum Co Ltd 溶接性にすぐれたＡｌ−Ｍｇ−Ｓｉ系合金押出材
JP2908929B2 (ja) * 1992-03-04 1999-06-23 株式会社神戸製鋼所 アルミニウム合金製自動車衝撃吸収部材
JP3291768B2 (ja) 1992-06-23 2002-06-10 三菱アルミニウム株式会社 塗装焼付け硬化性のすぐれたＡｌ合金板材
JP3670706B2 (ja) * 1995-03-29 2005-07-13 新日本製鐵株式会社 曲げ加工性に優れた高強度アルミニウム合金押出型材の製造方法
JPH09176806A (ja) 1995-12-26 1997-07-08 Furukawa Electric Co Ltd:The 焼付け硬化性に優れるＡｌ−Ｍｇ−Ｓｉ系アルミニウム合金板材の製造方法
JPH1030158A (ja) * 1996-07-18 1998-02-03 Furukawa Electric Co Ltd:The 加工性に優れたアルミニウム合金製自動車用配管材の製造方法
JPH10245650A (ja) * 1997-03-03 1998-09-14 Kobe Steel Ltd 溶接用Ａｌ−Ｍｇ−Ｓｉ系合金
JP3450209B2 (ja) * 1998-03-31 2003-09-22 古河電気工業株式会社 車両ボディ用フレーム材の製造方法
JP3691254B2 (ja) * 1998-08-07 2005-09-07 三菱アルミニウム株式会社 サイドメンバー用Ａｌ−Ｍｇ−Ｓｉ系合金押出形材及びその製造方法
JP3580195B2 (ja) * 1999-03-17 2004-10-20 日本軽金属株式会社 断面形状が安定し機械的性質が良好なアルミニウムの略中空材の製造方法
EP1041165A1 (en) * 1999-04-02 2000-10-04 Kabushiki Kaisha Kobe Seiko Sho Shock absorbing material
JP2003268473A (ja) * 2000-03-02 2003-09-25 Kobe Steel Ltd 耐圧壊割れ性に優れるＡｌ−Ｍｇ−Ｓｉ系アルミニウム合金押出材
JP3502939B2 (ja) * 2000-06-19 2004-03-02 株式会社神戸製鋼所 衝撃エネルギー吸収性に優れるＡｌ−Ｍｇ−Ｓｉ系アルミニウム合金押出形材
JP2002235158A (ja) 2001-02-05 2002-08-23 Nippon Steel Corp 曲げ加工性に優れた高強度アルミニウム合金押出形材の製造方法
JP3757831B2 (ja) * 2001-07-26 2006-03-22 日本軽金属株式会社 衝撃エネルギー吸収性能に優れたＡｌ−Ｍｇ−Ｓｉ系アルミニウム合金押出材
JP3791408B2 (ja) * 2001-12-20 2006-06-28 三菱アルミニウム株式会社 曲げ加工性およびエネルギー吸収特性に優れたアルミニウム合金押出し材の製造方法
JP2003221636A (ja) * 2002-01-29 2003-08-08 Aisin Keikinzoku Co Ltd 耐衝撃破壊性に優れたＡｌ−Ｍｇ−Ｓｉ系アルミニウム合金押出形材
JP4138474B2 (ja) * 2002-12-26 2008-08-27 アイシン軽金属株式会社 塗装焼付け硬化性に優れたアルミニウム合金押出形材の製造方法
JP2003268474A (ja) * 2003-04-09 2003-09-25 Kobe Steel Ltd 衝撃エネルギー吸収性に優れるＡｌ−Ｍｇ−Ｓｉ系アルミニウム合金押出形材
JP2006097104A (ja) * 2004-09-30 2006-04-13 Toyota Motor Corp 塗装焼付け硬化性に優れた６０００系アルミニウム押出材及びその製造方法

Also Published As

Publication number Publication date
JP5166702B2 (ja) 2013-03-21
JP2007270218A (ja) 2007-10-18
CA2628229A1 (en) 2007-10-11
EP2006404A1 (en) 2008-12-24
WO2007114521A1 (ja) 2007-10-11
EP2006404A4 (en) 2009-12-16
CN101356294A (zh) 2009-01-28

Similar Documents

Publication Publication Date Title
EP0097319B1 (en) A cold-rolled aluminium-alloy sheet for forming and process for producing the same
KR20140114031A (ko) 베이킹 도장 경화성이 우수한 알루미늄 합금판
US20080078480A1 (en) Hot-and cold-formed aluminum alloy
WO2017207603A1 (en) 6xxx-series aluminium alloy forging stock material and method of manufacting thereof
JP5204793B2 (ja) 耐応力腐食割れ性に優れた高強度アルミニウム合金押出材
US20220389557A1 (en) Aluminum alloy precision plates
US12000026B2 (en) Aluminum alloy sheet for automotive structural member, automotive structural member, and method for manufacturing aluminum alloy sheet for automotive structural member
JPH027386B2 (zh)
CN106574327A (zh) 成形用铝合金板
US20090047171A1 (en) 6000-series aluminium extruded material superior in paint-baking hardenability and method for manufacturing the same
JP3681822B2 (ja) Ａｌ−Ｚｎ−Ｍｇ系合金押出材とその製造方法
JP5813358B2 (ja) 高成形性Ａｌ−Ｍｇ−Ｓｉ系合金板及びその製造方法
JP2844411B2 (ja) 冷間予成形可能な超塑性成形用アルミニウム合金板およびその製造方法
JP5050577B2 (ja) 深絞り性および耐焼付け軟化性に優れた成形加工用アルミニウム合金板及びその製造方法
JP6719219B2 (ja) 成形性に優れる高強度アルミニウム合金板及びその製造方法
JP3516566B2 (ja) 冷間鍛造用アルミニウム合金とその製造方法
JP2001032031A (ja) 耐応力腐食割れ性に優れた構造材用アルミニウム合金板
JP2008062255A (ja) キャビティ発生の少ないＡｌ−Ｍｇ−Ｓｉ系アルミニウム合金板の超塑性成形方法およびＡｌ−Ｍｇ−Ｓｉ系アルミニウム合金成形板
JP7432352B2 (ja) キャップ材用アルミニウム合金板及びその製造方法
JP5823010B2 (ja) 耐応力腐食割れ性に優れた自動車構造部材用高強度アルミニウム合金押出材
JPH11350058A (ja) 成形性及び焼き付け硬化性に優れるアルミニウム合金板及びその製造方法
JPH0447019B2 (zh)
JP5631379B2 (ja) 耐応力腐食割れ性に優れたバンパーレインフォース用高強度アルミニウム合金押出材
JP4022497B2 (ja) アルミニウム合金パネルの製造方法
JP2011144410A (ja) 高成形性Ａｌ−Ｍｇ−Ｓｉ系合金板の製造方法

Legal Events

Date Code Title Description
AS Assignment

Owner name: TOYOTA JIDOSHA KABUSHIKI KAISHA, JAPAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:AONO, MASAMICHI;MIYAKI, TOSHITAKA;YOSHIDA, TOMOO;REEL/FRAME:020918/0269

Effective date: 20071113

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION