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Information on AA5086 Aluminium

Hi, I'm an engineering student in NUS and I'm encountering some problems for my project. Can anyone help me with this question?

What is the composition of AA 5086 Aluminium? Trays made from AA5086 aluminium alloy are used to hold disk drives, which are then heat-treated at 150 °C for 2 hours by heating the trays. The aluminium alloy trays are manufactured by rolling, followed by heat treatment to give a well-defined, equiaxed grain structure. In an effort to save cost, the aluminium trays are bought in the as-rolled condition,without heat-treatment. However, when the trays are put in service,almost half of the disk drives fail after the heat treatment. Suggest a reason for the high failure rate of the disk drives and possible remedial measures.

Mr Ng
- Singapore
2000

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The chemical composition(wt%) of AA 5086 alloy is as follows:--

Si-0.4, Fe-0.5, Cu-0.1, Mn-0.2/0.7, Mg-3.5/4.5, Zn-0.25, Cr-0.05/0.25, Ti-0.15, Al-remainder.

Generally, the 1xxx,3xxx & 5xxx series wrought alloys do not respond to strengthening by heat treatment. Strength for these alloys are developed by strain hardening, usually by cold working, e.g., rolling during fabrication. The heat treatment you mentioned is a low temperature annealing process for recrystallisation, recovery & grain growth.

Regarding the failure of the disk drives, what type and mode of failure are they? Any surface pretreatment done on the trays after the heat treatment?

Best Regards,

Wong Soon Hing
- Singapore
2001

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I am an engineering student in Trinity college in Dublin, I study fatigue on welded joints for my thesis. I need to know the plain fatigue limit and the threshold value for welded specimen of AA 5086 Aluminium. I know that is very difficult but I hope someone can help me for example indicating to me some good web-sites where I could find these informations.

Thanks a lot for your availability, best regards

Giuseppe Crupi
Trinity College Dublin - Dublin, Ireland, Europe
2001

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Hi guys!
I am a postgraduate student of the University of Manchester. I need information for a pending course work and I will be happy if someone assisted me. Please can AA5086 alloy be used for marine applications. If ''Yes'' or ''No'' please give your reasons

Eugene Ogosi
University of Manchester - Manchester, Lancashire and United Kingdom
2006