SLS and MJF 3D printing process
The process flow of SLS: First, a thin layer of powder is spread evenly and evenly on the forming platform, where it is heated to a temperature close to sintering. The powder is then sintered by scanning each cross-section with a laser in a predetermined path; the platform is then moved down one layer, and the process is repeated until complete. After printing, the entire silo must be cooled before the part can be removed from the powder.
The process flow of MJF: First, a thin layer of powder is spread evenly and evenly on the forming platform, where it is heated to a temperature close to sintering. Slide a carriage with inkjet nozzles (similar to those used in desktop normal 2D printers) over the powder bed to spray the Fusing Agent on the powder. At the same time, a detailing agent that prevents powder sintering is sprayed near the edge of the part; a high-powered infrared heat source then illuminates the powder bed and sinters the areas where the flux was sprayed, while the rest of the powder remains unchanged. Repeat the process until all parts are built. Similar to SLS, MJF-printed parts are encapsulated in a powder that also needs to cool down before they can be removed.
Dimensional accuracy
Both MJF and SLS can provide industrial-grade 3D printing with high dimensional accuracy. The difference between the two is not very large. If you have to distinguish, MJF is slightly better in dimensional accuracy. This is mainly because the MJF printhead prints at 1200 DPI (or about 1 dot per 0.022mm), while the typical laser spot diameter of an SLS system is about 0.3-0.4mm; in addition, the detailed agent used in the MJF ) to help print small features and sharp edges.
It is worth noting that both techniques do not require support structures, allowing the creation of free-form models without any support removal marks, but both are prone to warping, so large flat areas must be avoided. In our testing, we found that MJF parts warped more easily than parts printed with SLS.
Appearance and Surface Quality
The flux currently used in MJF systems is black because dark materials absorb thermal radiation more effectively, which results in a light gray appearance of MJF parts that can be passed through an optional post-processing step to achieve a uniform black finish.
SLS parts are usually white and can be dyed any color.
Nylon surface
Parts printed with both techniques have a grainy surface with a matte feel, but both can be post-processed to a high standard. If aesthetic requirements are the main requirement, post-processing coloring is highly recommended.
Material properties
The main material used in both processes is PA 12 (nylon). SLS prints are slightly weaker in the print direction (Z direction), while MJF parts have superior strength and flexibility and more uniform mechanical properties.
However, SLS is a well-established, tried, and tested system. Whether it is manufacturers, service providers, or independent researchers, the performance of SLS materials is well documented, the application history is longer, and the documentation is comprehensive in all aspects. On the other hand, the important engineering properties of nylon offered by MJF, such as impact strength and creep properties, have not been widely available to the industry.
In addition, MJF is an open material platform. In the beginning, there was only one kind of PA material. Now MJF can provide materials such as PA11, PA+glass fiber beads, TPU, and even PP materials, full-color materials. It is foreseeable that HP this Strategies can accelerate the speed of material development, and the future can be expected.
On the whole, the performance of white nylon and black nylon is not much different, and the material performance of black nylon is better, and the future is more worth looking forward to.
Cost and lead time
Monkey.com provides a very competitive price for nylon printing on the entire network. No matter white nylon or black nylon, it maintains a high discount margin. In terms of performance, black nylon is slightly better and the price is slightly more expensive. Generally speaking, the general size is less than 300mm, and white nylon is cheaper. If the printing size is larger than 300mm but less than 380mm, it is cheaper to use MJF to print, and the larger size needs to be printed with large P770 equipment, and the cost will soar. Of course, if it is possible, you can also choose to split it into small prints.
The delivery time is generally not much different. Black nylon may have an advantage in delivery time due to a higher powder recovery rate and faster cooling rate. Of course, Magic Monkey.com provides 24 hours fast for both materials. Shipping options, I believe readers who have read this article carefully can also understand why the delivery time as an optional option will affect the production cost and price
Nylon printing and nylon material have the advantages of high-temperature resistance, high wear resistance, high toughness, high mechanical strength, etc. 3D printing nylon can be directly used in product accessories and has a very high forward-looking in the future mass customization.