My stock brake line had some nasty rusty patches in places, so it gave a leak. I want replace a part of it with a 3/16 copper tubes (0,9mm thick). Will they withstand pressure? Are there any successful examples?

 

.........why

 

Well, I came across on that article from science direct. http://64.90.169.191/applications/automotive/brake.html
It says copper/nickel 90/10 alloy is the best choice.

 

Copper brake lines would be a bad idea. These are 2 reasons off the top of my head - It will corrode when exposed to the elements, Its very soft and will expand and contrast with the temperatures your brakes fluid can get.

Stainless steel is what i would recommend

 

Copper alloy as someone already mentioned. It will last forever, it's cheap, and its generally available from your local autozone. Most OEMs use them for a reason.

Stainless steel would be incredibly difficult to work with unless you mean braided stainless lines. The burst pressure of copper vs stainless as far as hardlines goes is about the same. You'll never see 5000+psi so it doesn't really matter.

 

The nickle copper brake line material is extremely safe to use for brake line as that is one of the purposes it was designed for. Do not use pure copper line as it may not be of sufficient pressure rating and may rupture under hard braking pressure. It is also not corrosion resistant. It will work in a pinch but buy a good grade of material. Stainless lines are also a good option but are harder to work with. If making the lines yourself you will need a bender and flaring tool.