Recent Developments in Chemical Milling
Chemical milling, the process of using chemicals to dissolve portions of unwanted metals, was once used mainly on thinner metals and glass products. Today it can be used on slightly thicker and extremely larger products as well. Lines, designs, words and images can be engraved into the surfaces of these different materials, and the process is being improved upon constantly. According to Green Tech Focus, in 2009, TITAL GmbH in Germany completed their new chemical milling facility. This new facility is now able to etch parts up to 60 inches in length and weighing up to 661 pounds. In this facility, aluminum and titanium products are mainly used, and the process is done to remove any brittle casings the metal might have.
Acids or chemicals are able to react with metals, causing them to dissolve. In this way, layers can be melted off, and lines or designs can be produced. For the making of lines or designs, a light masking layer must first be applied to the metal parts that are not meant to be etched. However, if a whole layer is going to be chemically melted away, this step is unnecessary.
For the large metal objects used in the Germany facility, a large acid basin is used that is able to completely submerge the metal. In this case, the basin is 5.9 feet wide and 6.5 feet long. Because the acid can be very dangerous, the entire basin is located in a pit that is partially closed. This makes the acid basin less accessible to the majority of the workers. Only those skilled in the process should be exposed to it. The new facility allows the titanium and aluminum pieces to be easily milled, and also allows over twice as much material to be recycled. While it was a large investment, it was also a good investment for the company for the many benefits it provides.