# Sustainable Optimization of the Injection Molding Process Using Particle Swarm Optimization (PSO)
## 2 Literature Review  
Simultaneously, the mold must undergo pre-heating to an optimum temperature, facilitating adequate polymer flow during the filling phase and minimizing the risk of premature cooling that can lead to flow marks or incomplete fills [12; 14]. Establishing thermal equilibrium between the mold and melt significantly influences initial phase performance and mitigates internal stress formation within the part [6; 17]. Once the mold reaches the designated temperature, the clamping stage is initiated, wherein the mold halves are tightly secured with considerable clamping force. This process ensures that high-pressure injection of the molten material occurs without leakage. Insufficient clamping force can compromise the dimensional precision of the part and potentially damage the mold under repeated cycles [5; 18]. During the filling phase, molten polymer is injected into the mold cavity at high velocity, flowing through components like the sprue and runners. Uniform filling is crucial to prevent air entrapment, which could lead to voids or incomplete parts [7; 12]. Also, proper venting design must allow displaced air to escape, directly impacting molecular orientation and the final product's mechanical properties [9; 13]. Immediately after filling, the pressure-holding stage begins to counteract material shrinkage associated with cooling transitions. Precision control of holding pressure is vital; excessive pressure can induce residual stress, while insufficient pressure can lead to underpacking and result in dimensional inaccuracies [6; 20]. Injection molding has several intricate stages, significantly influencing molded products' final quality and precision. Mastery over each process step is essential for minimizing defects and ensuring consistent production outcomes. The initial phase involves preparing plastic raw materials, typically pellets. A critical step in this pre-processing phase is drying; improper moisture content can lead to undesirable outcomes such as material bubbling and surface blemishes, manifesting as structural weaknesses in the final products [14; 17]. Techniques such as dehumidification and hot air drying are employed to achieve optimal conditions for the raw materials, as consistent drying significantly governs melt quality. Following the drying process, raw materials are introduced into the injection molding machine, where controlled heating in the barrel progressively melts the plastic. Uniform temperature maintenance is paramount during this stage, as fluctuations can adversely affect viscosity, filling pattern instabilities, and variations in part weight and dimensions. A pertinent study highlighted the importance of adequate drying and consistent melt temperatures to minimize warpage and dimensional inconsistencies [14]. Simultaneously, the mold must undergo pre-heating to an optimum temperature, facilitating adequate polymer flow during the filling phase and minimizing the risk of premature cooling that can lead to flow marks or incomplete fills. Establishing thermal equilibrium between the mold and melt significantly influences initial phase performance and mitigates internal stress formation within the part. Once the mold reaches the designated temperature, the clamping stage is initiated, wherein the mold halves are tightly secured with considerable clamping force. This process ensures that high-pressure injection of the molten material occurs without leakage. Insufficient clamping force can compromise the dimensional precision of the part and potentially damage the mold under repeated cycles. During the filling phase, molten polymer is injected into the mold cavity at high velocity, flowing through components like the sprue and runners. Uniform filling is crucial to prevent air entrapment, which could lead to voids or incomplete parts. Also, proper venting design must allow displaced air to escape, directly impacting molecular orientation and the final product's mechanical properties.