Effect of Scandium Addition on Mechanical Properties and Corrosion Resistance of Medium Strength Al-Zn-Mg-Cu) Alloy

Al-Zn-Mg alloys are widely used construct material for wide range of application including automotive industry, building, and aviation. Scandium is rare earth metal, which modifies structure of semi-products and can lead to increasing of tensile and yield strength because of Al3Sc intermetallics of nanoscale size. This paper describes results of influence of small addition of scandium (0,08 wt. %) on mechanical and corrosion properties of cold-rolled sheets of 1913 alloy. 1913 is Russian medium strength corrosion resistant weldable Al-Zn-Mg alloy with addition of Cu for improvement of stress corrosion resistance and Mn with Zr for structure improvement. It is shown that addition of Sc transforms kinetics of artificial aging and accelerates decomposition of solid solution, besides tensile strength increases up to 50 MPa in artificially aged tempers. Changes in microstructure and quench sensitivity are described; results of intergranural corrosion, exfoliation and stress corrosion tests are introduced after different heat treatment including peak strength aging and overaging tempers.

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Influence of Heat Treatment on Stress-Corrosion Resistance of EN AW-AIZn5Mg1,5CuZr Alloy

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.199.424 ◽

2013 ◽

Vol 199 ◽

pp. 424-429

Author(s):

Lesław Kyzioł ◽

Kazimierz Czapczyk

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Corrosion Resistance ◽

Stress Corrosion ◽

Structural Changes ◽

High Stress ◽

Corrosion Properties ◽

Stress Cracking ◽

Suitable Heat Treatment ◽

Stress Corrosion Resistance

The aim of this study is to determine mechanical properties and stress-corrosion resistance of EN AW-AIZn5Mg1,5CuZr alloy from the aspect of microstructure changes depending on the applied heat treatment. Stress corrosion is caused by the effect of corrosion environment parallel to mechanical stress. It occurs when cracks appear in the metal which is exposed to a corrosion environment and static stretching stresses. The effect of the corrosion environment and stresses on the metal surface cause cracks which are placed perpendicularly to the direction of stretching stresses and may be intercrystalline, intracrystalline or mixed. Stress cracking observations show that distinct cracks are often preceded by the incubation phase. The intensity of microcracks in this phase can be determined by examining changes in mechanical properties caused by changes in alloy structures after various time intervals of the stress-corrosion experiment. This study outlines changes in mechanical properties and resistance of the aluminium alloy in question depending on the heat treatment parameters. Changes in mechanical and corrosion properties are reflected in the structural changes of EN AW-AIZn5Mg1,5CuZr alloy. In order to enhance stress-corrosion resistance and obtain good mechanical properties in Al-Zn-Mg alloys (Zn+Mg>5%), a special heat treatment with cooling with a stop is used. This publication shows suitable heat treatment parameters which guarantee good mechanical properties and high stress-corrosion resistance.

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Stress-corrosion resistance of the EN AW-AlZn5Mg1,5CuZr alloy in different heat treatment states

Polish Maritime Research ◽

10.2478/pomr-2013-0039 ◽

2013 ◽

Vol 20 (4) ◽

pp. 39-44

Author(s):

Lesław Kyzioł

Keyword(s):

Heat Treatment ◽

Corrosion Resistance ◽

Aluminium Alloy ◽

Stress Corrosion ◽

Alloy System ◽

Mg Alloys ◽

Corrosion Properties ◽

Chemical Constitution ◽

Stress Corrosion Resistance ◽

Mechanical And Corrosion Properties

ABSTRACT The effect of heat treatment of the plastically worked 7000 series Al-Zn-Mg aluminium alloy system on its stress-corrosion resistance is examined. For the same chemical constitution, the effect of heat treatment on mechanical and corrosion properties of Al-Zn-Mg alloys systems is remarkable. It was proved that a parameter having significant effect on corrosion properties of the alloy is the rate of alloy cooling after heat treatment. This conclusion is confirmed by observation of structural forms which fully reflect mechanical and corrosion properties of the alloy.

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The Atmospheric Stress-Corrosion Resistance of some Forged High Strength Aluminium Alloys and an Assessment of the Effects of a Step-Quench into Molten Salt

Aeronautical Quarterly ◽

10.1017/s000192590000158x ◽

1959 ◽

Vol 10 (4) ◽

pp. 297-318 ◽

Cited By ~ 1

Author(s):

W. M. Doyle ◽

R. G. Jones

Keyword(s):

Corrosion Resistance ◽

Stress Corrosion ◽

Aluminium Alloys ◽

Transverse Direction ◽

Copper Alloys ◽

High Strength ◽

Plate Material ◽

Short Transverse ◽

Wide Range ◽

Stress Corrosion Resistance

Since the introduction of aluminium-zinc-magnesium-copper alloys, investigations into the behaviour of these high strength materials, over a wide range of composition, have indicated the significance of corrosion as a factor affecting the cracking of these alloys after prolonged stressing at loads below the ultimate tensile strength of the material.Most of the previous work designed to assess the stress-corrosion resistance of aluminium-zinc-magnesium-copper alloys (D.T.D. 683A*) was carried out on sheet and plate material and the present investigation is concerned with the examination of these materials in the form of large hand-forged slabs, tested in the short transverse direction.

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UNILOY 326

Alloy Digest ◽

10.31399/asm.ad.ss0241 ◽

1970 ◽

Vol 19 (7) ◽

Keyword(s):

Stainless Steel ◽

Corrosion Resistance ◽

Physical Properties ◽

Stress Corrosion ◽

Tensile Properties ◽

High Strength ◽

Heat Treating ◽

Distinct Advantage ◽

Two Phase ◽

Stress Corrosion Resistance

Abstract UNILOY 326 is a two-phase, ferromagnetic stainless steel characterized by high strength and very good general and stress corrosion resistance. It has distinct advantage for the fastener industry. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: SS-241. Producer or source: Cyclops.

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