AMT Vapor Smoothing: an effective surface treatment process in 3D printing

AMT Vapor Smoothing: an effective surface treatment process in 3D printing

Vapor smoothing, which can transform a rough layered surface into a smooth surface, has become an important post-processing technology in the field of 3D printing. As the demand for 3D printed parts grows, achieving a high-quality surface finish is critical. Post-processing technology for 3D printed objects can play a role in enhancing aesthetics and improving mechanical properties. By solving the common problems of visible layer lines and rough surfaces in 3D printing, steam smoothing is an effective option for achieving professional-quality results. So what is steam smoothing in 3D printing?

What is steam smoothing in 3D printing?

Steam smoothing is a finishing technique for 3D printing, also known as "chemical steam smoothing," "steam polishing," or "steam fusion," in which printed parts are exposed to evaporating solvents that help eliminate surface layer lines of 3D printed parts.

The chemical vapor used in this process reacts with the surface of the material, which melts and partially dissolves, resulting in a smoother surface. By using this technique, 3D printed parts can obtain a smooth and glossy surface. Steam smoothing can be seen as an excellent finishing option that can add significant value to 3D printing. The technology is widely used in the automotive and aerospace industries, where parts must be as smooth and perfect as possible for optimal function and beauty.

MJF PA 12 3D printing comparison: Print state (left) and steam melting (right)

How does steam smoothing work?

Steam smoothing is an efficient way to achieve a smooth surface finish on a variety of materials without removing any material. It uses a finishing agent and controlled chemical melting to achieve the desired result, during which the proper temperature and pressure are maintained to obtain the desired effect and avoid damage to the workpiece.

3D printing steam smoothing process illustration

Here is a step-by-step guide to how the fully automated smoothing process works:

Step 1 - Place the workpiece into a sealed treatment chamber with finishing agent (usually FA 326). The finishing agent is commonly used for a variety of plastic materials, but depending on the material being treated, different finishing agents can be used.

Step 2 - Place the workpiece in the smoothing chamber and heat the reagent to a specific temperature to create steam around the part. Maintaining temperature and pressure control is essential to ensure that steam is evenly distributed on the surface.

Step 3 - Steam adheres to the surface of the part to form a controlled chemical melt. This melting reduces peaks and valleys on the surface by liquefying and redistributing the material, resulting in a smoother surface.

Step 4 - Chemical melting also enhances the shine and gloss of the material. The degree of gloss enhancement depends on the processing parameters and finishing agent.

Step 5 - Once the reagent has done its job, the smoothing chamber is heated to remove the steam and finishing agent, which is then collected in a barrel. The workpiece does not have any residue, and no material is removed during the process.

Step 6 - After smoothing is completed, the workpiece can undergo secondary treatment such as dyeing, painting or any other surface treatment.

Types of technologies and materials available

Steam smoothing is widely used in a variety of 3D printing materials, including polymers and elastomers, the most commonly used being PA 12 and PA 11. Steam fusion post-treatment technology can be combined with dyeing to obtain a smooth and colorful component surface.