Aisin Keikinzoku Co., Ltd.

Sumitomo Chemical Company, Limited

Karin Shibata

Tomoo Yoshida

Hiroshi Tabuchi

Hidetoshi Takagi

A method for producing an aluminum alloy extruded material includes: subjecting, to extrusion processing, a casted billet obtained from an aluminum alloy containing 6.0 to 8.0% by mass of Zn, 1.50 to 3.50% by mass of Mg, 0.20 to 1.50% by mass of Cu, 0.10 to 0.25% by mass of Zr, 0.005 to 0.05% by mass of Ti, 0.3% by mass or less of Mn, 0.25% by mass or less of Sr, contents of Mn, Zr and Sr being 0.10 to 0.50% by mass, with the balance being Al and inevitable impurities to obtain an extruded material; cooling the extruded material, immediately after the extrusion processing, to 100&#xb0; C. or less at a cooling rate of 50 to 750&#xb0; C./min; then subjecting the extruded material to a heat treatment at 110 to 270&#xb0; C. and subjecting the extruded material to plastic working within a prescribed time after the heat treatment.

Method for producing aluminum alloy extruded material

An aluminum alloy extruded material that exhibits high strength by air cooling immediately after extrusion processing and excellent stress corrosion cracking resistance, and a method for manufacturing the same are disclosed. The material includes, by mass: 6.0 to 8.0% of Zn, 1.50 to 2.70% of Mg, 0.20 to 1.50% of Cu, 0.005 to 0.05% of Ti, 0.10 to 0.25% of Zr, 0.3% or less of Mn, 0.05% or less of Cr, 0.25% or less of Sr, and 0.10 to 0.50% in total among Zr, Mn, Cr and Sr, with the balance being Al and unavoidable impurities.

High strength aluminum alloy extruded material with excellent corrosion resistance and favorable quenching properties and manufacturing method therefor

A method for manufacturing a bent article using an aluminum alloy with high strength and excellent corrosion resistance comprises: extruding a cast billet of an aluminum alloy including, by mass, 6.0 to 8.0% Zn, 1.50 to 3.50% Mg, 0.20 to 1.50% Cu, 0.10 to 0.25% Zr, 0.005 to 0.05% Ti, 0.3% or less Mn, 0.25% or less Sr, and the balance Al with inevitable impurities to obtain an extruded material; cooling the extruded material at an average rate of 500&#xb0; C./min or less immediately after the extrusion processing; subjecting the cooled extruded material to preliminary heating treatment at a temperature within a range of 140 to 260&#xb0; C. for 30 to 120 seconds within a predetermined time after the extrusion processing; bending the extruded material having undergone the preliminary heating treatment to obtain a bent article; and subjecting the bent article to artificial aging treatment.

Method for manufacturing bent article using aluminum alloy

A method includes: preparing a molten aluminum alloy consisting of 0.3-0.8 mass % Mg, 0.5-1.2 mass % Si, 0.3 mass % or more excess Si relative to the MgSi stoichiometric composition, 0.05-0.4 mass % Cu, 0.2-0.4 mass % Mn, 0.1-0.3 mass % Cr, 0.2 mass % or less Fe, 0.2 mass % or less Zr, and 0.005-0.1 mass % Ti, with the balance being aluminum and unavoidable impurities; casting the alloy into a billet at a speed of 80 mm/min or more and a cooling rate of 15&#xb0; C./sec or more; extruding the billet into an extruded product; water cooling the product immediately after extrusion at 500&#xb0; C./min or more; and artificially aging the product, thereby yielding an extruded product with fatigue strength of 140 MPa or more, fatigue ratio of 0.45 or more, an interval between striations on a fatigue fracture surface of 5.0 &#x3bc;m or less, and a maximum length of Al&#x2014;Fe&#x2014;Si crystallized products of 10 &#x3bc;m or less.

Growing community of inventors

Oyabe, Japan

Karin Shibata