All You Need to Know About Cold Spray Additive Manufacturing

The various additive manufacturing technologies available today can seem endless, though they often fall into one of about seven categories, but not all of them. Take, for example, cold spray additive manufacturing. Cold spray is a technique which involves the use of a high-velocity gas jet – at up to four times the speed of sound – which accelerates powder particles onto a substrate, usually a metal, over a distance of approximately 25mm. This technique can form a coating over the piece, or, in the case of AM, can be used to form an entire part. The cold spray process itself was developed by researchers at the Institute of Theoretical and Applied Mechanics (ITAM) of the Siberian Branch of the Russian Academy of Science, in the 1980s. The group realized that it was possible to coat solid particles with a gas flow at room stagnation temperature.

In terms of cold spray additive manufacturing, this is a technique which uses cold spraying to form entire parts (or to fix broken or damaged parts). It is done with a spray nozzle and robotic arms that either are moving a substrate or the nozzle itself, with different benefits and limitations to each method. But what are the advantages of using this method? What about the applications? We took a closer look.

Photo credit: VRC Metal Systems

Benefits and Limitations of Cold Spray Additive Manufacturing

One of the main advantages of cold spray in general over thermal spraying is that, because the temperature does not go above 800 degrees, it can be used for temperature-sensitive materials (including nanostructured) and oxygen sensitive (such as titanium and aluminum, both of which oxidize) as the particles do not melt. Furthermore, the production time is short – shorter than SLM, EBM, and LMD, and the product size list unlimited. Additionally, cold spraying can be undertaken with a number of different metals and their compounds. These include aluminum, nickel, copper, steel and titanium, as well as precious metals – silver, gold, and platinum – and refractory materials. Furthermore, cold spray additive manufacturing has a particular advantage for the repairing of corroded or damaged parts, particularly in the aerospace industry.