Stainless Steel To Aluminium

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Is it possible to join this two material (steel to aluminium) with TIG..?this is my current project to complete my degree..i need suggestion about dis..tq
Reply:As far as fusion welding, no. (Fusion welding meaning that both pieces are melted and allowed to flow together to form the weld with or without the addition of a filler material.)A similar question was asked in an earlier thread about joining copper to stainless: http://weldingweb.com/vbb/showthread.php?t=19534Here's the relevant part as to why it won't work, while this concerns copper and stainless the same goes for aluminum to stainless: Originally Posted by TensaitekiAside from the substantial difference in melting points making a puddle extremely difficult to form, let alone control, the main reason is metallurgical.While mild steel and stainless can easily dissolve a very small amount of copper (where it becomes a weak deoxidizer) amounts over a certain limit (amounts vary by alloy but are usually under 0.1%) will cause hot-cracking.When you have a mixture of two metals that have substantially different melting points and are not completely soluble in one another, upon cooling the metal with the higher melting point (the stainless, in this case) will begin to solidify and form grains (crystals) that begin to grow together. The lower melting point metal (copper, in this case) will still be liquid and will be forced into the space between the grains.As cooling continues, the lower melting point metal will begin to solidify, however, at the same time the already solidified metal (stainless) will be contracting as it cools, causing the grains to try and pull apart. Since the lower melting point metal (copper) is neither fully solid enough to resist or stretch nor liquid enough to flow, it will simply crack (think, soggy, moldy bread).This is the same reason that you cannot use any of the arc welding processes to weld aluminum, to any type of steel (or iron) either.
Reply:expected answer was given acttly...i have done so many trial about this joining..but not even succeed yet..sometimes it looks complete join when i adjusting the current while welding process.. Originally Posted by TensaitekiWhat degree is this for anyway? I guessing it isn't a welding degree, if it was you should've learned by now that you can't fusion weld aluminum directly to stainless (or any other type of steel).
Reply:I'm glad you're not getting a degree in Welding Techology.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Al to SS?  Like oil and water.  Limited to friction and explosion welding. (with marginal to poor results)We have a part at work that requires an al-ss weld.  It is a living nightmare.  We were friction welding it, but had low yields due to fractures when the part was heated (CTE stress).  (It is for a jet engine part.)Now, we are explosion welding with somewhat better results.Brazing?  MAYBE if plated first.  Might have low yields due to brittle compounds and fracture problems.  3 out of 4 aerospace braze vendors no quoted the job.
Reply:Originally Posted by handoo69Is it possible to join this two material (steel to aluminium) with TIG..?tq