How do you bend Titanium sheet metal?

[Kyle_in_Tex]

I made my wife a cookie sheet out of some Ti6Al4v (grade 5) that I had laying around for years. I think it is about .035" thick. I put it on the brake we have at work and started bending. I wanted about a 1/2" lip on the long edge for strength and a place to grab with a pot holder. When it got close to 90 degrees, it started cracking and in a couple places, actually split in half. I ended up tig welding it back together at the bend.

Pretty expensive cookie sheet I know. But the most expensive part was sanding it down to a decent surface finish. I'd say it has a 16 finish or so.

Probably should've engraved my name and the date on it so when my children's children's children use it, they'll remember my name. LOL.

 

[DuckSlayer1017]

I've always heard that it needed to be hot formed. Try heating it then putting it in the brake.

 

[Kyle_in_Tex]

Does anyone know how hot?

 

[DuckSlayer1017]

I once toured a shop that did it. They had it red hot and then let it cool in the die so it wouldn't move. A quick Google search said 1200F.

 

[Baby Grand]

You do know that titanium will burn if heated hot enough in air, right?
Can be a very difficult fire to extinguish in a hurry.
The powder is especially "sparky", so be careful with any grinding or sawing.

http://titanium.com/wp-content/uploads/2010/10/Material-Safety-Data-Sheet.pdf

Some forming & general info:
Warm forming titanium parts - TheFabricator.com

Some more info:
Forming of the Titanium and Titanium Alloys: Part One :: Total Materia Article

I love the material - I have been wearing a fairly inexpensive titanium watch for the past 6 or 7 years that has a titanium case, back and wrist band. It's eerily light and has held up well to the abuse I've dished out to it.

 

[Pepsiboy]

Kyle,

having over 20 years experience in precision sheet metal, I would say that you are trying to bend it to sharp. Measure the thickness with a micrometer. Then use a forming die that has an INSIDE radius that is 3 times that thickness. Also, being it will be a baking sheet, I would not bend it more than 60 degrees. As you get close to 90 degrees, the stress on the OUTSIDE radius of the bend is VERY high. When I would be working with Titanium, I would do what is called a "Soft form" to get 90 degrees, NEVER a "Hard form" as the metal COULD fracture along the outside radius.

For the finish, I would use a dual action orbital sander with 120 grit pads, then go to 180 grit or 220 grit. After getting it very even finish with that, go to a 400 grit, then to 800 grit. Take your time and be patient with the finish. After using the 800 grit, I would TRY making a pad of 4-0 (0000 that is) of steel wool. Wash very well with mild soap and water, and dry. HOWEVER, Titanium SHOULD have a VERY smooth surface to start with. If your sheet DOES NOT, it probably is an inferior grade. What I have worked with was always labeled as "T-3". :2cents: Best of luck.

Dave

 

[Kyle_in_Tex]

Thanks guys. Great info.

 

[Dr_Zinj]

So much for my idea of turning titanium sheet metal into a nice set of armored plate.

 

[Kyle_in_Tex]

Kyle,

having over 20 years experience in precision sheet metal, I would say that you are trying to bend it to sharp. Measure the thickness with a micrometer. Then use a forming die that has an INSIDE radius that is 3 times that thickness. Also, being it will be a baking sheet, I would not bend it more than 60 degrees. As you get close to 90 degrees, the stress on the OUTSIDE radius of the bend is VERY high. When I would be working with Titanium, I would do what is called a "Soft form" to get 90 degrees, NEVER a "Hard form" as the metal COULD fracture along the outside radius.

For the finish, I would use a dual action orbital sander with 120 grit pads, then go to 180 grit or 220 grit. After getting it very even finish with that, go to a 400 grit, then to 800 grit. Take your time and be patient with the finish. After using the 800 grit, I would TRY making a pad of 4-0 (0000 that is) of steel wool. Wash very well with mild soap and water, and dry. HOWEVER, Titanium SHOULD have a VERY smooth surface to start with. If your sheet DOES NOT, it probably is an inferior grade. What I have worked with was always labeled as "T-3". :2cents: Best of luck.

Dave

I think the larger radius is the secret for us backyard benders. The heat would be difficult to do in a small time operation.

 

[Kyle_in_Tex]

So much for my idea of turning titanium sheet metal into a nice set of armored plate.

What you really want is a suit of beryllium armor with kevlar undersuit.