Reseach On 3D Printing Materials And Processes Of Sn-Bi Low Melting Point Metal

This study has investigated the Tin-based alloy material of the low-melting metal used as Fused Deposition Modeling. By means of literature review, take the Sn-Bi alloy as the research object. In this study, the performance and the technological parameter that used in the FDM of Two alloys components of Sn-40%Bi and Sn-58%Bi are investigated and discussed. By Alloy Smelting, Extrusion and drawing obtained successfully a filament diameter of 3.0 mm. then the two alloying composition above mationed were used to investigate the melting and deposition behavior of each, so as to determine the optimal process parameters. The main results are listed as follows:1、The research utilizes FDM system to deposit two alloys components of Sn-40%Bi and Sn-58%Bi. The experimental of fused deposition process results show that the non-eutectic Sn-40%Bi solder retained its as-deposited shape more consistently and uniformity. The main reason is due to a solid-liquid mixture state. Non-eutectic alloy can be better continuity and uniformity throughout the deposited lines. The non-eutectic Sn-40%Bi perform the most consistent deposition results when the temperature at the nozzle of 215 ℃.2、When the FDM extrusion temperature is 215 ℃, studying the ratio of between x-y velocity and extrusion velocity. Experiments were carried out Non-eutectic alloy can be better continuity and uniformity throughout the deposited lines with a ratio(x-y velocity to extrusion velocity) of 1.5. Finally, the research presented here utilizes the JOYE-3D FDM 2020D system to deposit an example of 2D shapes.3、Compared to the as-cast microstructure, the microstructure of metal is refined obviously. Because Tin-bismuth low-melting alloy in fused deposition extrusion molding solidification cooling rate very fast.4、Through the use of a FDM system with plunger-type nozzle to process Tin-bismuth low-melting alloy. It’s difficult to ensure continuous deposition results. The molten metals couldn’t form piston effect in piston type nozzle, because the relatively low viscosities of the molten metals when compared to traditional FDM thermoplastic materials. So it can not provide stable extrusion pressure for the melted-metal inside the nozzle. At the same time, the nozzle could be blocked due to the molten metal reflux instead.