# Effects of Solid Die Types in Complex and Large-Scale Aluminum Profile Extrusion
## 5 Conclusions  
In this study, three different types of solid dies used complex profile extrusion were designed. Steady-state and transient simulations were conducted using HyperXtrude 2017 software based on the \begin{table}
\begin{tabular}{c c c} \hline \hline \multirow{2}{*}{**Ram Speed (mm/s)**} & \multicolumn{2}{c}{**Length of Transverse Weld**} \\ \cline{2-3}  & **The Pocket Die (mm)** & **The Spread Die (mm)** \\ \hline
1 & 3497 & 5742 \\
5 & 3624 & 7385 \\
9 & 3718 & 8985 \\ \hline \hline \end{tabular}
\end{table} 
Table 7: Transverse weld parameters with increasing ram speeds. Figure 19: Percentage of the new material with the distance of the charge weld in the extruded product of the dies: (**a**) The pocket die; (**b**) The spread die. ALE algorithm. A series of parameters obtained from simulation such as metal flow pattern, extrusion force, extrudate temperature, die deformation, and transverse weld length were analyzed. The effect of ram speeds on extrusion parameters was also evaluated. The conclusions of this study can be drawn as follows:  
1. Using the traditional flat die has the advantage of achieving a more uniform temperature distribution in the extruded product when compared to other solid dies. The extrusion force of this die is about 5% smaller than that of the pocket die. This type of die has a simple structure and is easy to fabricate. However, the needed bearing length is longer than other solid die types, which is undesirable in extrusion practice. Moreover, the deformation of the flat-face die is the largest, the maximum die deflection at a speed ram of 1 mm/s up to 0.17 mm; This may exceed the permissible tolerance of the product. Deformation reduction solutions for this die need to be considered further. When using the flat-face die, a low ram speed can be used to reduce die deformation. Finally, using the traditional flat die is not suitable for extruding complex profiles. 2. Using the pocket extrusion die has many advantages compared to other types of solid dies, the velocity is more balanced; the deformation is minimal; transverse welding length is half shorter when compared to the spread die. Moreover, when the ram speed increases, the value of VRD changes little and the die deformation is maintained stably, and the welding line length does not increase significantly (about 221 mm when increasing the ram speed from 1 to 9 mm/s). This die type is the best choice to ensure quality and productivity in extruding aluminum products. However, the pocket and flat-face dies have the disadvantage of being unable to extrude products with sizes larger than the container diameter of the extruder. 3. Using the spread die has the advantage that the required extrusion force is the smallest when compared to other solid dies, which is about 40% of the extrusion force required for pocket extruders with the same product profile. It is an extremely effective solution when it is necessary to reduce a large amount of extrusion force or extruding products on small machines with product sizes larger than the extruder diameter. This die type has been growing rapidly in recent years because it can increase the flexibility of production. However, this die type is difficult to design to be able to uniformly distribute the flow in extruded products. Hence, using a pocket and variable bearing lengths is necessary to balance the metal flow for extruding complex product profiles. The more complicated die structure makes the fabrication cost bigger than other types of solid dies. The difference in temperature distribution in the extrusion product of this die is much larger than in other cases, which can be overcome by the increase in temperature for the die plates. The spread extrusion forming the transverse horizontal welding length is twice as long as the pocket die, and the charge weld length is increased rapidly with increasing ram speed (about 3243 mm when increasing the ram speed from 1 to 9 mm/s).