Titanium and titanium alloy surface is silver-white, with excellent corrosion resistance, if you want to titanium various coloring treatment. Titanium coloring methods are about three or three: atmospheric oxidation, anodic oxidation, chemical treatment. The most commonly used method is anodic oxidation. So let's do an experiment to visualize the anodic oxidation process.
First of all, we're going to prepare an aqueous solution. Aqueous solution is distilled water plus sulfuric acid, the concentration of sulfuric acid is very low, less than 1:10.
The experiment began with a spent titanium plate, the anode, and a thick copper wire as the cathode, placed together in the electrolyte. It starts bubbling when you turn it on.
Once OK, start the coloring process by placing the titanium to be colored in an aqueous solution. We had a voltage of 15V, and I didn't know how long it was going to take at first, so I wanted to say a good one, more than 10 minutes on the right, and notice that the aqueous solution was slowly turning into a blue solution of copper sulfate, but it wasn't very good. Later, I ground it and rework, the surface of the ground, ground bright, re-power 15V, about 2 minutes of electricity, much better.
After this test, I think, in order to make a uniform and beautiful color, the first thing to do is to grind the surface carefully. I used 800 sandpaper to grind the surface, and the finished surface is very smooth. In addition, I found that during the process of anodic treatment, power can be cut off first to see the treatment status, and then decide whether to continue to power on. Another interesting phenomenon is that the copper wire from the anode melts away to the cathode.
Anodized voltage and color comparison table, very useful.
