Aluminum question?

[jet]

I asked this question on the Northriver thread but I think many people are overlooking the thread now. Alum. boats are made of many types of marine grade Alum. 5000 series. What is the difference between the 5052,5083,5086 or the 56789? I am sure they all have different peoperties.

I have found many boat builders use one type, or a combination of types of Alum. during construction. When they all use different types is it just opinions on Alum. or is there a real reason, or just cost?

Oh great wise I-Fish can you shed light on this question.... If not, I can climb the mountain and see the the Dali-lama.


Jet~~~

[This message has been edited by jet (edited 02-19-2001).]

[Bait O' Eggs]

Jet
This question intriqued me so I did a little looking. I work for a place that buys quite a bit of aluminum diamond plate and I have a catalog from Alaska Copper & Brass. In the catalog they have a brief description of some of the alloys. They dont go on to describe the percents of the different materials on each grade in there catalog, but said the following:

5052
For many years, until the advent of 5083 and 5086, this alloy was the highest strength non heat treatable alloy commercially available. Although easily welded it is not recommended for brazing and soldering applications. Excellent corrosion resistance, particularly in marine applications, and adapts to most mechanical and finishing processes although the heavier anodic films may take on a yellowish cast. Fair machining with proper set up. Typical end uses include fuel tanks, truck trailer side panels, small boat hulls, truck cabs, bumpers, storage tanks, and pressure vessels.

5086
Has excellent corrosions resistance and weldability. Can be anodized for increased corrosion resistance, but does not led itself to decorative applications. Not meant to be a machining alloy, but can be machined fairly well with proper applications. Because of its relatively high magnesium content, the workability rating would be only fair. Typical end uses are marine craft containers, railroad cars, structures and elevator cars.

I did a quick search on line and found the following link. I believe the different grades just have different percentages of magnesium and other materials.
http://www.metalshorts.com/aac_ins.htm

I know there is a big difference in price on the grades. We put the diamond plate on school locker rooms on the lockers to help keep the kids from tearing up the lockers. We can buy a 3003 grade for about 1.92/lb and the 5052 grade is about $3.00/lb. You cannot tell the difference by looking at them. We have never noticed getting that tarnished look from 3003 we were warned about by buying a cheaper grade of aluminum. I wouldnt want my boat made from 3003 but it does fine in the schools.

Maybe we have a metalugical specialist on ifish who wants to go off on this topic.

[DF]

Interesting topic.
I am not an expert on metal but the info I just read here has helped me learn a little to. I am learning to weld alumminum... ITS PRETTY HARD. any way not really related to the topic but. IM GOIN FISHING TODAY!


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A bad day fishing is better than a good day at work

[jet]

Thanks Bait

This is one of those questions you just kinda of wonder about. Not the important ones like to fish ot not to fish.

Maybe we can toss this question to our resident weld inspector in Spokane. Another Weldcraft owner.


Jet

[Big Willie]

Well...hmmm. 5052 is your all-around alloy. With the -H (5052-H32, 5052-H34) designating how 'hard' or how 'hardened' the material is for further strength. 5000 series aluminum can't be heat treated because of it's properties. 6000 series, for example 6061, can be heat treated and therefore much stronger. The -T (6061-T6) denotes the degree of heat treating, the temper of the material. Hope this helps a little.
-Gary

[huntorfish?]

5052 is the most readily available and lends itself to sheet metal forming and is most widely used in lighter gauge application ie .125 thick or less. It has excellent formability while providing good resistance in marine applications. It is most popular in the 1/4 hard (h-32) and 1/2 hard (h-34)conditions. In these conditions the metal can stand substantial bends and forms without crazing. Uses that you know would be products like a large mainframe computer cabinet or even the sides and box that house your home stereo receiver. 5086 is used because it is the most weldable. It has excellent weldability comparitive to other grades of aluminum. It also has similar alloying elements to 5052 to make it more of a workability/color match. It seems to be much more popular in Europe than it is here. 6061 as mentioned earlier is tempered by heattreating normally by solution or artificially aging. It does not lend itself to good formability in the hardened condition because it tends to craze or orange peel when putting a tight radius or bend in the metal. It is still used in the boat industry normally in drift boat bottoms ie willie. Many internal parts around the engine mounts of sleds are 6000 series aluminum for the added strenth and wear. I hope this helps.

[Fish4Fun]

I had put this on the North River posting but figured it would go better here.
Hope this will help you guys a little on boat materials.

The 5000 series marine grade aluminum alloy is specifically made for full-time saltwater applications. ( 5086 & 5083 ) ALCOA, aluminum Company of America, put a plate of this aluminum in Narragansett Bay, RI for thirty
years and took it out because nothing was happening.. The balance of a boat's construction consists of 5086 aluminum. This grade of aluminum is the choice where both strength and yield are important. Both of these aluminum alloys are the absolute best. If you've ever seen a U.S. Coast Guard 47 footer than you've seen 5083 and 5086 aluminum at work afloat.

Weldcraft - 3/16 5086 bottoms 1/8-5052 Sides

Duckworth - 3/16 bottoms and 1/8 sides both are 5086 - H116

North River - Bottom and sides very in thickness 5086 material.

Fish 4 Fun

[boater]

some companys do use 5086 for the sides, probly all the boats with no formed ribs in the sides, but the boats with the formed ribs are probly all 5052, try this, take a side off a 20 foot duckworth and put each end on a saw horse and try to stand in the middle of it, now take a side off a 20 foot weldcraft with the formed ribs and do the same, what one is stucturaly stronger ??

[Rippenlips]

boater, you are comparing apples to oranges. If you weld a shelf in the 5086, it is probably 30 % stronger than the 5052 and is more resistent to denting. Thats why the different boat Co. use different materials. I think I'm addicted to this web site. I'm at work and missing a meeting to type.
Jon

[boater]

i dont agree, but everyone has there own opinion i guess.

[jet]

Rippin

If you weld a shelf to the inside the full lenght, would you see the heated area on the outside? and if you heat metal in a area dont you loose strenght? It seems to me that heating in the field area has to decerase some of its strenght. I am not a welder but have welded steel and that is how I see it. If you pay 30k for a boat it needs to look like it was professionaly built not put together in my garage.

Jet~~~

[Fish4Fun]

jet, you are right about seeing the welding on the outside of the boat. When I had my Duckworth you could see where welds on the inside were, especially after it was etched and polished to a mirror finish.

Fish 4 Fun

[Rippenlips]

Jet, you are 100% correct. You can see all the ribbing on all the expensive boats if you look real close. Any welding on Aluminum weakens it also. But it is still very strong. You can go to Lincoln Electrics home page and read all about it. Sorry Boater, I don't mean any disrespect. If I get some time I'll try to get some more info on the different grades of Aluminum. I just don't remember what, were and when I got the info between 5052 and 5086 and I could have it backwards but I thought the higher the number the stronger the Aluminum. Thats why plains are made out of 6000 and 7000 series Aluminum and you can't weld 7000 series due to weakening it. Thats why plains are all riveted. I could probably call Pacific metals under the Ross Island bridge and they would explain it.
Jon

[boater]

http://www.matweb.com/GetIndex2.asp