User:Lihediudiu/sandbox

thumb 3D printing supporting material [1] is used in the fused deposition molding (FDM) 3D printing technology. During the printing process, the parts of the suspended structure or hollow structure of the auxiliary products are formed, and the materials to be removed after the printing is completed. Currently, there are three types of support materials and technologies: The first is a strip type frame materials [2], the same material as the body will be printed into a loose structure in the parts that need to be supported. After printing, remove the supporting material from the main material by physical means (such as using a knife or other tools). This method has some shortcomings, such as difficult operation, difficult removal of the supporting material itself and easy destruction of the main material. Second is dissolved type support materials [3], which is mainly water-soluble materials such as polyvinyl alcohol, acrylic acid copolymer and so on [4], After printing, the finished product is immersed in water, and the water-soluble characteristic of the supporting material is utilized to remove it. The surface quality of the product itself is better protected. However, water-soluble materials have poor cohesion with bulk materials, and there is usually a swelling process before dissolution, sometimes causing some damage to the products. It is also reported that a HIPS material [5] can be dissolved in limonene, but the cost of using limonene is higher. Thirdly, decomposed 3D printing support material [6]. Which has reported by "Mechanical Engineering Materials" No.5,2018. When the printed parts are finished, they are immersed in acidic liquids at a certain temperature, and the supporting materials will be decomposed into gases and removed. This decomposition material use polyformaldehyde (POM) as the basic material and is composed by adding other materials. POM is a common engineering plastics with low price and good supporting effect. It has no effect on the appearance of products after decomposition. Moreover, the decomposition characteristics of POM materials can open up the application of FDM 3D printed products in fields such as EPC, which has a good prospect.