Classifications

• • 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
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21B—ROLLING OF METAL
  • B21B3/00—Rolling materials of special alloys so far as the composition of the alloy requires or permits special rolling methods or sequences ; Rolling of aluminium, copper, zinc or other non-ferrous metals
• • 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
  • C22C21/08—Alloys based on aluminium with magnesium as the next major constituent with silicon
• • 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
  • C22F1/05—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 of the Al-Si-Mg type, i.e. containing silicon and magnesium in approximately equal proportions

Definitions

• the present invention refers to the production of strips and sheets from heat-treatable aluminum alloys, containing less than 1% copper which strips and sheets can reach their maximum strength by subsequent simple aging treatment.
• the process of the present invention is especially suitable for aluminum-magnesium-silicon alloys, but is also suitable for aluminum-zinc-magnesium alloys with low magnesium content.
• aluminummagnesium-silicon alloy herein refers to all aluminum alloys with a chemical composition lying between the following limits:
• the basic metal can be aluminum of commercial purity (i.e. according to ASTN B209) as well as aluminum of high or highest purity (refined aluminum).
• AA6011, AA6061 or AA6063 according to the Registration Record of Aluminum Association Alloy Designations and Chemical Composition Limites for Wrought Aluminum Alloys, published by The American Association, 420 Lexington Ave., N.Y., N.Y., 10017.
• the aluminum-zinc-magnesium alloys referred to in this invention may contain Percent Zinc 3.5-5 Magnesium 0.5-1.5 Copper 1 Aluminum Balance Furthermore, these alloys may contain additions like manganese, chromium or other elements. Because of their 3,392,062 Patented July 9, 1968 ice relatively low magnesium content compared to materials like e.g. AA7075, AA7079, AA7178 etc. these alloys are designated as low alloyed.
• the present invention allows a noticeable increase in the transit speed, thus permitting an economic production of sheets and strips in essentially copper-free, heat-treatable aluminnum alloys suitable for artificially aging.
• the initial slab or plate has to be homogenized and hot-rolled while still in the warm condition.
• the hot-rolled strip which should have a temperature of more than 350 C., preferably more than 400 C., then immediately has to be cooled down to a temperature of 200 C., or less preferably quenched to room temperature in less than 2 minutes, preferably less than 1 minute.
• the material is coldrolled with a thickness reduction of at least 20%, then solution-treated in a continuous furnace for less than 1 minute, preferably less than 30 seconds and immediately quenched after leaving the furnace.
• Such sheets and strips can, at least, be naturally aged or preferably artificially aged.
• Hot-rolling speeds for the subsequent passes have to be chosen individually in order to take advantage of the heat produced by rolling down the material, to maintain the metal temperature above 350 C., preferably above 400 C.
• the process of the invention has the advantage of maintaining the homogenized condition of the initial slab or plate during hot rolling and subsequently in the strip leaving the hot mill by a quench.
• sheets or strips manufactured according to the present invention can pass a homogenization furnace of given length with a speed which is many times greater than that necessary with the common methods. This rise in efiiciency, therefore, correspondingly achieves an economical increase.
• the procedure according to the invention is especially suitable for the continuous production of strips.
• the finished products in this case are sheets instead of strips.
• the rolling slab is soaked for 6 hours at 530 C. (metal temperature). This is followed by hotrolling it down to a thickness of 7 mm., for instance, starting with a metal temperature of 500 C.
• the plate temperature after hot-rolling was not less than 380 C.
• the last hot-rolling pass is followed by an immediate quench of the plate in water, the temperature of the plate falling down to 50-80 C.
• the transit speed is 30 m./minute, i.e. the total heating cycle takes 20 seconds: 10 seconds are used for heating up the metal, Whilst the remaining 10 seconds count as soaking time. For the subsequent quenching, air blast or water .is used. Finally the strip or sheet is aged by reheating the material for 14 hours at a temperature of 160 C.
• the strip produced in this way has the following mechanical strength properties:
• Brinell No. (IO/2.5) 101 An aluminum plant is known where the hot-rolled strip is cooled with water spray before coiling. However, cooling the strip at the run-out of the rolling mill in this plant is not done to maintain the homogeneous structure, but to facilitate the handling of the strip only. They do not roll any heat-treatable aluminum alloys at all in this plant, but exclusively pure aluminum and the non-heattreatable aluminum-manganese alloys.
• Banbury, Oxfordshire, a few years ago did not suggest the use of strip from heat-treatable aluminum alloys immediately quenched after hot-rolling as a basic material for the production of heat-treatable sheet and strip from aluminum alloys by cold-rolling followed by a heat-treatment in a continuous furnace.
• the present invention therefore is based on a special treatment combination resulting in a distinct increased effect compared with that attainable by common procedures.
• step (2) the hot-rolling temperature is maintained at not less than 400 C. and in step (3) the quenching is done from a temperature of at least 400 C. down to a temperature below 200 C. in less than 2 minutes.
• step (3) the quenching is done in order that the temperature of the hot-rolled member falls below 200 C. in less than 1 minute.
• step (4) The process as described in claim 1, wherein in step (4) the duration of solution-heat-treatment is less than 30 seconds.
• step (2) the hot-rolling temperature is maintained at not less than 400 C.
• the quenching of the rot rolled :member is done from the temperature of at least 400 C. down to below 200 C. in less than 1 minute, and in step (4) the duration of the solution-heat-treatment is of less than 30 seconds.
• step (2) the hot-rolling temperature is maintained at not less than 400 C.
• the quenching of the hot rolled member is done from a temperature of at least 400 C. down to 5080 C. in less than one minute, and in step (4) the duration of the solution-heat-treatment is of less than 30 seconds.
• step (2) the hot-rolling temperature is maintained at not less than 400 C.
• the quenching of the hot rolled member is done from the temperature of at least 400 C. down to room temperature in less than 1 minute, and in step (4) the duration of the solution-heat-treatment is of less than 30 seconds.

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)
• Metal Rolling (AREA)
• Heat Treatment Of Strip Materials And Filament Materials (AREA)

Applications Claiming Priority (1)

Publications (1)

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Family Applications (1)

Country Status (5)

Cited By (19)

Families Citing this family (6)

Citations (5)

• 1964
  • 1964-08-27 CH CH1124364A patent/CH480883A/de not_active IP Right Cessation
  • 1964-10-07 DE DESCH35916A patent/DE1279940B/de active Pending
• 1965
  • 1965-08-26 NL NL6511155A patent/NL6511155A/xx unknown
  • 1965-08-27 GB GB36958/65A patent/GB1055687A/en not_active Expired
  • 1965-08-27 US US483345A patent/US3392062A/en not_active Expired - Lifetime

Patent Citations (5)

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