5005 aluminium grade any good?

[shakey78]

Well this is an easy one just wanted to know what your thoughts are with 5005 grade aluminium for boat building? I'm starting a test of my own to see how 5005 Vs 5083 in some salt control tests to see what it will do, but I'd like to hear what all your thoughts are? And we will see what happens.

[daiquiri]

It is a low-strength and low-magnesium alloy, with higher percentage of copper when compared to more common marine-grade aluminum alloys, like 5083 or 5086. As such, I wouldn't use it for hull construction. If you don't have access to better alloys perhaps it could be ok for your boat's superstructure, if properly protected against corrosion. However, if your boat has to comply to some class rule, the 5005 probably won't be accepted, because it will hardly meet the corrosion and mechanical resistance standards.
In any case, my best advice is to contact Ad Hoc for an opinion (http://www.boatdesign.net/forums/profile/ad-hoc.html), he has a vast technical knowledge about aluminum alloys.
Cheers

[shakey78]

Hmm interesting, now I will do a strength test as well, I don't know how important the strength would be on a 4.5mtr bass boat but corrosion is the main area I was looking at, as I have found that today's alloys are better than alot of people think they are.

Would love to know if anyone has done some real tests them selfs ? Or any other input would be great.

Also testing some 6006 grade in salt electrolis

[shakey78]

Well so far salt electrolise test on 5005 is showing no signs of deterioation nor the marine 5083.

[Ad Hoc]

Originally Posted by shakey78

Well this is an easy one just wanted to know what your thoughts are with 5005 grade aluminium for boat building? .

In a word...don't!

Originally Posted by shakey78

Also testing some 6006 grade in salt electrolis

Why are you selecting non-marine specific aluminium alloys?

Either someone has given you a shed load for free or you've got some poor advice, or you're just wishing to go against the grain, for some bizarre reason.

There is no sound logical reason for selecting 5005 or 6006 aluminium alloys for marine use.

[shakey78]

Im building a 5 mtr bass boat using 5083 grade but was keen to find out for myself in testing the grades so far salt test is not different, I doing a strength test tonite with heat and non heat and different angle pull see what that turns up

[Ad Hoc]

Originally Posted by shakey78

... so far salt test is not different..

I assume you're doing your testing in accordance with ASSET G66 & G67 testing to establish a common datum and if your results mean anything?..or some other method, to establish its suitability?

Originally Posted by shakey78

...I doing a strength test tonite with heat and non heat and different angle pull see what that turns up

This too shall be interesting. Are you performing bend testing as per approved methods used by Class, such as BS EN 910. And how is your test equipment calibrated?

[Ad Hoc]

Originally Posted by shakey78

... I doing a strength test tonite with heat and non heat and different angle pull see what that turns up

So, what turned up??

[shakey78]

Well the standards are my own and I work for a company that makes metal from rocks and we are not a large company like one steel or blue scope, we buy raw materials from them, and testing steel blends is our job, and I just wanted to see if there was a huge difference between the two grades, I know large scale 5005 would not be used but maybe could be used for 5mtr below, as my tests so far are surprising maybe I have a good batch of 5005 or a cheap 5083...... Will post again later out of time

[Ad Hoc]

Originally Posted by shakey78

Well the standards are my own ..

Well, with your own experiments and testing, what eqpt you use to test, is the eqpt calibrated and what methods you use and how you take the measurements and how frequently etc, it is very hard to say whether what you're doing can yield meaningful results.

[shakey78]

I have acces to a Q1200 which is ample in giving me the data i need and with heat and frezzing conditions or what eva senario i wish to create.

So far it has turned up some questions on the aluminium specs but i would say a small craft 4-5 meter fishing boat 5005 would be an option as it has not corrided at all and as for strength unless you get it to almost liquid state its holds up to tensile strength better than i thought it would even after mig welding, but 5083 with good heat soak and welded was realy strong. But you would have to be jumping 6-7 meter waves in a boat or running aground in your fishing boat at full speed to see the weakness of 5005. but that is my testing for my own info and I would still recomend using 5083 as its always better to have more strength than not enough.


As for Yielding meaningful results why not try it your self as i have, And not for any reason but my own intrests, i was not setting out to rewright the standards of aluminium boat building just wanted to see.

[Ad Hoc]

Originally Posted by shakey78

As for Yielding meaningful results why not try it your self as i have, ..

I have many times on many different alloys and different tests

[Mr Efficiency]

In the 1980's I came across an old WWII fighter plane ( A P-40, I believe) that had crashed on a remote beach. It was in shallow water at low tide. The alloy skin of that plane was in remarkably good condition, like new almost. The thing that came to my mind, was how was a non-marine aluminium not corroded after 40 years in salt water.

[Ad Hoc]

Originally Posted by Mr Efficiency

The thing that came to my mind, was how was a non-marine aluminium not corroded after 40 years in salt water.

There needs to be an electrolyte (sea water) and a driving force (electrical potential - from dissimilar metals) for corrosion to take place. Secondly depending upon the pH, there may or may not be corrosion on aluminium.

So, without seeing the wreck, impossible to say for sure, but likely not enough criteria were satisfied to initiate corrosion.

[Mr Efficiency]

Originally Posted by Ad Hoc

There needs to be an electrolyte (sea water) and a driving force (electrical potential - from dissimilar metals) for corrosion to take place. Secondly depending upon the pH, there may or may not be corrosion on aluminium.

So, without seeing the wreck, impossible to say for sure, but likely not enough criteria were satisfied to initiate corrosion.

There was rusted steel evident in the wings where the guns had been retrieved, as well as around the engine. But the aluminium skin was bright and smooth like new. Seemed remarkable to me.