Permanant Metal to Metal adhesive Reccomendations 1

[MadEngineer13]

I am working on a project wich will require two pieces of aluminum to be permanantly bonded with adhesive. The material will either be 6061 or 7075. Curently we are planning on using 1/32 inch roll pins for allignment and strenght once the adhesive has cured. This part will be subjected to moderate climate/environmental changes, and moderate shocks as well. The shock axis will be parallel to the glue line. I also need a long set up time, probably one or two hours, and the glue should be thin enough to penetrate small features. Does anyone have any suggestions or experience with this sort of problem? Thanks, MadEngineer13

 

[Goahead]

Your detailed explanation does not describe the joint type, which is critical to successful joining. Shear stress is preferred in the adhesive plane. The purpose of roll pins is not clear to me. The long set up time will exclude some adhesive types like epoxy that might cure in this time frame. Curing by heating might solve your problem if it can be accommodated by the design.

http://www.welding-advisers.com/

 

[KENAT]

Can you talk to a vendor, for instance loctite? You obviously have to be a bit careful that they don't sell you down the river but from my limited dealings with them loctite actually seem pretty good.

Make sure you're talking to the apps guy not just the sales guy.

There are adhesives that cure by heat or even UV light (may not work in your app) that may help with the working time issue.

KENAT, probably the least qualified checker you'll ever meet...

 

[tomwalz]

3M has been helpful in the past.

Thomas J. Walz
Carbide Processors, Inc.

http://www.carbideprocessors.com

 

[MintJulep]

You need to quantify things.

Subjective terms like "moderate climate/environmental changes" and "moderate shocks" and "small features" are meaningless.

You also need to understand the difference between "open time" and "cure" or "set up" time, and be able to define your actual needs.

You may want to get yourself a copy of ASTM D6465 "Standard Guide for Selecting Aerospace and General Purpose Adhesives and Sealants", which provides an excellent overview of the things you - as the designer - need to think about when designing a bonded joint.

 

[MadEngineer13]

Thanks for the Help! I should clarify that the stresses on the glued joint are in the shear plane. As for the environmental changes, this device will be carried on someone's person, so it has to be able to withstand any environmental extremes that the weather might dish out. The purpose behind the roll pins is two fold. I need some method of accurately locating what are essentially two aluminum shells, and It also seems that the addition of roll pins would add some additional strenghth to the joint.
Thanks for the help, and I will definately check with the references mentioned above.

 

[6060842]

Hi,

In my industry (Rail), we use a lot of structural adhesives, nameley Plexus and sometimes Sikaflex. I have a sample of an Aluminium lap joint bonded with Plexus sat on my desk, which everyone likes to give a good bending every visit. It must be 3 years old now and the aluminium is just staring to fracture but the bond is as good as day one

Its also good for sticking collegues boots to the floor (Sorry John!)

Anyway ther you go

 

[BrianPetersen]

JB Weld ? ? ?

(I've broken and fixed a few things with that stuff)

 

[unclesyd]

I would first look at either an epoxy or a methacrylate adhesive for your application.

You can give either of these sources a call.

http://www.masterbond.com/

http://www.gluguru.com/Methacrylates.htm#HYsolMetha

 

[mighoser]

We use EA9395 for certain metal to metal bonds where welding is not possible. You will need to prepare the aluminum properly (prime) to achieve the correct joint strength.

 

[IFRs]

3M makes some high bond strength tapes

 

[berkshire]

EA9309NA is a high peel Strength epoxy used for joining Aluminum. EA9395 is supposed to be an improvement on that I am not convinced yet, that it is.
B.E.

 

[SincoTC]

We use 3M VHB, acrylic double sided tapes on metal to metal or composites, and provided the surfaces are properly cleaned they are great! However, you won't get a long set-up time, once they touch, that's it done. You need to ensure the parts are correctly positioned before they touch (your dowels would be good) and the design should take into account the thickness which can be up to a millimeter or so. The foam gives them almost total immunity from shock loading and seals well against moisture ingress.

Where the slight flexibility or the thicness of the tape is a problem we use Loctite, but I would be wary of shock loads and the limited assembly time.

Trevor Clarke. (R & D) Scientific Instruments.Somerset. UK

SW2007x64 SP3.0 Pentium P4 3.6Ghz, 4Gb Ram ATI FireGL V7100 Driver: 8.323.0.0
SW2007x32 SP4.0 Pentium P4 3.6Ghz, 2Gb Ram NVIDIA Quadro FX 500 Driver: 6.14.10.7756

 

[rb1957]

one choice you'll have to make early on is room temp or high temp cure. high temp is more difficult (needs an autoclave) but in my experience is more tolerant to process variations than room temp.

another choice is are you going to do the work yourself or sub it out ? in my business i've had experience with Fleet industries (in the US) and Fokker (in Europe).

IHMO, lose the chicken rivets on sheet-to-sheet bonding ... you might use them when bonding a stringer to a panel.

 

[smcadman]

Look into adhesives used in the automotive industry to bond body panels, such as Fusor Metal Bonding Adhesive 108B.

http://www.lordfulfillment.com/upload/UI3000.pdf

Flores

 

[GregLocock]

raychem make some nice reliable epoxy that I've used for metal bonding. It's green and expensive.

Cheers

Greg Locock

SIGlease see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[coatingengineer]

Hi.

Polyamide-imide (PAI) is an excellent choice for structural adhesive.

You'll find the compound has exceptional wetting characteristics (important for bonding), thermal stability and resistance to corrosion.

Good luck!



William Gunnar

http://www.IndustrialCoatingsWorld.com