Titanium is known for its corrosion resistance, strength, durability, and light weight. It is commonly found in rocks, clay, sand, and soil in ilmenite and rutile. When those two minerals are processed, they produce titanium tetrachloride, which, by adding sodium, produces pure titanium.
The preparation process for titanium is complex and reactive. Until the 1950s, titanium was a laboratory curiosity. With the development of special processing methods, it became commercially available for industrial use.
The unique qualities of titanium has made it a perfect metal for a variety of applications. It has half the density of iron at 4.5g/cm3 and twice the density of aluminum with very low electrical and thermal conductivity and is paramagnetic, weakly attracted to magnets. The tensile and yield strength of titanium is similar to stainless steel.
Etched titanium has found multiple applications in the health and medical fields due to its biocompatibility and its processing methods that do not require any after processing operations.
There are two methods for etching titanium, which are hydrochloric acid and electrolytic. Hydrochloric acid (HF) is preferred because it produces excellent quality and can be serialized. The electrolytic process involves an electrolyte, anode, and cathode to remove titanium by reverse plating.
Aerospace uses approximately 80% of all titanium produced because of its strength to weight ratio. Its other applications include medical applications for implants due to its mechanical properties. The chemical industry uses titanium for its resistance to chemical environments.
Photochemical etching produces patterns on metal by dissolving portions of the metal using an oxidizing reagent. Hydrofluoric acid, or a combination of nitric and hydrofluoric acid, are used in wet photochemical etching of titanium. The etching reagent is HF, while nitric acid contains hydrogen absorption.
The ideal thickness of the sheets of titanium for etching are between 25 micrometers (µm) and 1.0 mm. The photoresistant pattern is applied to the substrate layer of the titanium sheet before chemical etching processing, which can be either negative or positive.
There is a long list of uses for titanium etchings, which include dental implants, eye surgery blades, hearing aids, cardiac rhythm management, and cranial mesh. One of the main qualities of titanium etched products for medical use is titanium’s biocompatibility, how it interacts with the human body.
The benefits to titanium etching are low cost, limitless part complexity, and short lead times. The tooling for titanium etching can be changed and adapted easily without the need for extra preparation. Since titanium etching does not use heat or mechanical force, components do not require any after process treatments such as deburring or flattening.