Anodizing titanium is a popular way to add bright color to titanium projects. In addition to adding color, anodized titanium also offers wear resistance to the part as well. Colors that can be achieved this way fall into the Bronze, Purple, Blue, Light Blue, Gold, Rose, Magenta, Teal and Green ranges.
While this range offers plenty of color variations, certain colors, like Red, are impossible to achieve through anodizing due to the limits of the anodizing process.
Below is a Anodized Titanium color chart along with Voltage used to produce the color. The range here is from 0 volts to 100 volts. The very first bolt listed as '0' is the default un-anodized color for example.
Titanium Anodizing Process –
Titanium is cleaned and prepared by going through a cleaning process that ends with an ultrasonic cleaner. After this, the parts are put into an acid bath to prepare the titanium surface for anodizing. The Acid bath etches the Titanium and allows for bright and vibrant colors to be achieved consistently.
Using precise DC voltage and Amperage* (amps), titanium parts are placed in a bath with both positive and negative currents that allow for the anodizing process to form. This allows for a constant and uniform color to anodize the part. For parts where multiple colors are desired, the process is achieved in much the same way, but by changing the DC voltage to reflect the different colors desired.
DC voltage determines the color of the part. In titanium anodizing, voltage ranges from 10 to 100 volts.
Why Titanium –
Titanium is as strong as steel, 45% lighter than steel and doesn’t rust! Titanium is also a great metal for extremely hot situations where steel breaks down and lighter metals like aluminum become liquid. This is the main reason Titanium gained high overall acceptance in the Aerospace field, be that NASA or our more common commercial airplanes. The need for more fuel-efficient aircraft forces the move to lighter and stronger parts.
Titanium is one of the most common materials used for biomedical applications due to its strong corrosive resistance and excellent biocompatibility.
Being the 9th most abundant element in the Earth’s crust, titanium is found in small amounts occur in virtually every rock. Around 90% of all titanium in the Earth’s crust is found in a mineral called ilmenite.
Titanium is an amazing metal, but we mine titanium about 10 times more for its use as titanium dioxide than titanium metal. Titanium Dioxide is very common in high-quality white paints to increase reflectivity and whiteness.*NOTE - The use of both Acid and DC voltage in this process mandate care and safety protocols be taken. Please do not attempt to replicate. This is not intended to be used as a Do-It-Yourself reference manual, but to explain the process that we use to anodize titanium parts for customers.