Experimental investigation of temperature field and formability of compact fused granulation fabrication barrel

To address the problems of material agglomeration caused by unreasonable temperature field in compact screw extruders, an original Heat Break-like Structure (HBS) was introduced to realize accurate zonal control of the temperature field within the barrel. A novel barrel was iteratively designed through temperature field simulation. The temperature gradient across the feeding zone can be linearly adjusted by altering the internal wall thickness and the external wall depth of HBS. After optimization, the overall length of the device was reduced by 30 %, and the temperature difference across feeding zone reached 30.9 °C, 6.92 times higher than that of traditional structure. In addition, the PLA material was formed by an iteratively optimized Fused Granulation Fabrication (FGF) barrel. The tensile strength reached 41.67 MPa when the feed temperature was 160 °C and the printing temperature was 195 °C. However, the tensile strength dropped to 34.25 MPa when the feed temperature was 155 °C and the printing temperature was 210 °C. The iterative development of this novel compact FGF device eliminates the need for filament preparation, simplifying the manufacturing process, and holds great significance for achieving a low-carbon economy.