Working with titanium sheet
Posted: Sun Dec 16, 2018 8:02 pm
I have never worked with Ti, but I need to make a bunch of parts with .071"-.078" titanium sheet. I will try to work with Grade 5 6AL-4V first, but if I can't bend and weld it then I suppose I could use Grade 2 CP-2.
I bought some on eBay which is coming from China, but I think that I will be using a domestic supplier for future orders. I am not finding the Alibaba ordering system very user friendly. The first supplier that I contacted wanted to do the deal outside of Alibaba; this seemed like a red flag (pun intended).
With the sheet, I cut two pieces: 5" X 4" and 5" X 1". I then bend it by hammering it on a 4 1/2" OD mild steel pipe. Then I grind the pieces so that they fit up together for a single weld bead.
My questions are:
(1) Will this be hard to cut? The 6AL-4V is annealed.
(2) Will I be able to pound on it with a sledgehammer to bend it, or will I have to heat it and then pound on it? I will cover the steel pipe so that it doesn't contaminate the Ti.
(3) Is it overly challenging for a noob to weld 6AL-4V? I bought the proper filler rods: ERTi-5 for the Grade 5 and ERTi-2 for the Grade 2. I have never welded on Ti before, but I need to learn how.
(4) Are my instincts correct to buy the sheet from a domestic supplier? I think I will have enough trouble cutting, bending, grinding, cleaning and welding the Ti. I just don't want to introduce delays or QC problems.
I am confident that I would be able to weld on the Grade 2, but I really want the Grade 5 for my application. Strong and light!
I may also be encountering an issue with galvanic corrosion. I want to use Grade 12.9 steel bolts. The shank of the bolt will be in a hole in the Ti. I could use plastic washers against the Ti so that I could use a steel nut. I really don't want to spring for Ti bolts.
What I have read about galvanic corrosion leads me to believe that the steel bolt (shank) will suffer the consequences of the dissimilar metals. The Ti part that I am making will spend its life inside a bicycle tire, so no high temperatures and very little moisture. The tire gets bald after about 6-12 months, and all of the bolts come out at that point so I would be in a position to inspect the bolts for corrosion and replace if necessary. I may use latex tire sealant in there, but I imagine that I am on my own with that slimy mess.
I bought some on eBay which is coming from China, but I think that I will be using a domestic supplier for future orders. I am not finding the Alibaba ordering system very user friendly. The first supplier that I contacted wanted to do the deal outside of Alibaba; this seemed like a red flag (pun intended).
With the sheet, I cut two pieces: 5" X 4" and 5" X 1". I then bend it by hammering it on a 4 1/2" OD mild steel pipe. Then I grind the pieces so that they fit up together for a single weld bead.
My questions are:
(1) Will this be hard to cut? The 6AL-4V is annealed.
(2) Will I be able to pound on it with a sledgehammer to bend it, or will I have to heat it and then pound on it? I will cover the steel pipe so that it doesn't contaminate the Ti.
(3) Is it overly challenging for a noob to weld 6AL-4V? I bought the proper filler rods: ERTi-5 for the Grade 5 and ERTi-2 for the Grade 2. I have never welded on Ti before, but I need to learn how.
(4) Are my instincts correct to buy the sheet from a domestic supplier? I think I will have enough trouble cutting, bending, grinding, cleaning and welding the Ti. I just don't want to introduce delays or QC problems.
I am confident that I would be able to weld on the Grade 2, but I really want the Grade 5 for my application. Strong and light!
I may also be encountering an issue with galvanic corrosion. I want to use Grade 12.9 steel bolts. The shank of the bolt will be in a hole in the Ti. I could use plastic washers against the Ti so that I could use a steel nut. I really don't want to spring for Ti bolts.
What I have read about galvanic corrosion leads me to believe that the steel bolt (shank) will suffer the consequences of the dissimilar metals. The Ti part that I am making will spend its life inside a bicycle tire, so no high temperatures and very little moisture. The tire gets bald after about 6-12 months, and all of the bolts come out at that point so I would be in a position to inspect the bolts for corrosion and replace if necessary. I may use latex tire sealant in there, but I imagine that I am on my own with that slimy mess.