Parts printed with Cold Metal Fusion have the advantages of high strength, high precision, and high color. They can be used in aerospace, automotive manufacturing, medical device manufacturing, and many other fields. This material has a wide range of applications and is being adopted by more and more companies.
Cold metal fusion technology is a cutting-edge 3D printing manufacturing method that enables the manufacture of high-precision, high-quality metal parts in a short period of time. Compared with traditional metal processing methods, cold metal fusion technology can reduce material waste, save production costs, and also reduce production cycle and improve production efficiency.
SLS technology is a core part of cold metal fusion technology, and its advantage is that it can be produced using a variety of metal materials, including titanium, stainless steel, aluminum alloys and many more. This technology can provide more room for innovation and development in the manufacturing industry, and the application field is also expanding. For example, in aviation, automotive, medical equipment and other fields, cold metal fusion technology has begun to be widely used.
Although cold metal fusion is a multi-step process from digital design to final metal parts, it can be a production method for mass parts
In the CMF process inside the SLS machine, the SLS machine must have open parameters or pre-installed material profiles to adjust the temperature and other settings according to the requirements of the metal feedstock. The temperature of the CMF is much lower (below 80°C) than any SLS machine used for printing, hence the word “cold” used in Cold Metal Fusion. The metal is not melted in this process, but only a polymer.
The advantage of cold metal fusion is its high production efficiency, the ability to produce high-quality metal parts, and the ability to use it for mass production. Through digital design, human error can be reduced and the accuracy and quality of parts can be improved. Although its temperature is lower than that of traditional SLS machines, cold metal fusion is able to meet the needs of metal fabrication, bringing the potential to make a huge difference in manufacturing. After each section, a new layer of raw material is spread over the build layer, laser sinters it, and the process is repeated again and again until it is completed, without the need for a support structure. The result is a blank part made of plastic filled with metal powder, which means that any metal in powder metallurgy can be used and the cost of the part is greatly reduced.
Once completed, the parts need to be cleaned and depowdered, and the inventors say that the billet parts have high strength and stability and can be automated by water or air pressure. The durability of the green parts further enables mechanical turning, milling, drilling and grinding before the metal is sintered. Due to the low temperature of the whole process, all unused surplus metal raw materials can be reused next time. From here, just like in the metal injection molding (MIM) process, the part is chemically degreased, removing most of the polymer from the part, leaving the degreased part ready to produce the complete metal part in the final stage of the sintering furnace. The final section is smaller than the originally printed part.
All 3D printed parts made with polymer binders and metals (wire 3D printing, metal binder jetting) shrink after the polymer is removed and the part is sintered. Steel has a shrinkage rate of 15% and titanium has a shrinkage rate of 12%. There is no special software or calculation. Simply enlarge the steel part by 15% in the CAD program and the final part will be fully up to specification.
Cold metal fusion materials and equipment
There are currently materials available for the cold metal fusion process, including stainless steel 316L, stainless steel 17-4PH, tool steel M2, titanium Ti6Al4V, titanium CP-Ti (grade 1) and tungsten, and another tool steel H13, Inconel 625 and aluminum 6061 is currently under development.
The process requires an SLS printer, a skim station (with solvent) and a sintering furnace (type MIM). Strictly speaking, the degreasing and sintering steps can be outsourced because these additional equipment are expensive and these steps do require some expertise. While theoretically, any open SLS machine can handle this raw material, some adjustments and testing are required, and each brand of SLS machine is different.
More 3D printer manufacturers are expected to join, including select manufacturers of post-processing machines. This CMF club is called the Cold Metal Fusion League. The Alliance of Device and Software Manufacturers has partnered to provide bundles to help users get started with CMF without having a device yet, and they have packaged their products into two bundles: CMF LabSystem and CMF JobShop.
More bundles and options are in development. Alternatively, customized production solutions can be designed and created based on the required parts or business needs.
