A Systematic Survey of FDM Process Parameter Optimization and Their Influence on Part Characteristics <s> 218 <s> Rapid Prototyping (RP) technology has been advanced to fabricate initial prototypes from various materials. Stratasys’ Fused Deposition Modeling (FDM) is one of the typical RP processes that provide functional prototypes of ABS plastic. In order to predict the behavior of final ABS parts, it is critical to understand the material properties of the raw FDM process material, and the effect that FDM build parameters have on composite material properties. In this paper, we seek t the properties of ABS parts fabricated by the FDM 1650. Using the Design of Experiment (DOE) approach, the process parameters of FDM, such as raster orientation, air gap, bead width, color, and model temperature were examined. Tensile strengths of crisscross specimens, [45 °/-45°], cross specimens, [0 °/90°], and directionally fabricated tensile specimens ([0°] and [90 °]) were measured and compared with the injection molded FDMABS P400 material. For the FDM parts made with a –0.003” air gap, the typical tensile strength ranged between 65 percent and 72 percent of the strength of injection molded ABS P400. From the experiment s, several build rules for designing FDM parts were obtained. <s> BIB001 </s> A Systematic Survey of FDM Process Parameter Optimization and Their Influence on Part Characteristics <s> 218 <s> Several important factors must be taken into consideration to maximise the efficiency of rapid prototyping (RP) processes. The ability to select the optimal orientation of a build direction is one of the most critical factors in using RP processes, since it affects the quality of the prototyped part, the support structure and the build time. This study aims to determine the optimal part orientation that improves the average weighted surface roughness (AWSR) generated from the stair stepping effect. It also minimises the build time including the structure of the support in fabricating a completely freeform part. To avoid pre-selection operation, which is often troublesome and time-consuming, the genetic algorithm, that considers the fuzzy weight for surface roughness and build time, is used to determine the optimal orientation. The validity of the proposed algorithm is demonstrated by several examples using different RP systems and compared with previous works. The algorithm can help RP users select the be... <s> BIB002 </s> A Systematic Survey of FDM Process Parameter Optimization and Their Influence on Part Characteristics <s> 218 <s> Purpose – The following research seeks to focus on optimizing the fused deposition modeling (FDM) process of RP systems.Design/methodology/approach – Early stages of this study are based on the Taguchi method in establishing rapid prototyping building factors and their various levels. The ultimate tensile strength, dimension accuracy and surface roughness (SR), are analyzed. Through analysis of variance (ANOVA) and contribution approximation, significant building factors of each quality characteristic and optimal factors level combinations of each best quality characteristic are obtained. The main steps are setting the weight for each quality characteristic of the previous Taguchi method, obtaining the estimated multiple building quality characteristics through integrating the Gray theory, and obtaining a set of optimal building factors. Finally, the result is verified by the Gray theory and the technique for order preference by similarity to ideal solution (TOPSIS) evaluation method.Findings – It is prov... <s> BIB003 </s> A Systematic Survey of FDM Process Parameter Optimization and Their Influence on Part Characteristics <s> 218 <s> A finite element analysis (FEA) model was previously developed by the current authors to simulate the fused deposition modelling (FDM) process. The model considered coupled thermal and mechanical phenomena and incorporated an element activation function to mimic the additive nature of FDM. Due to repetitive heating and cooling in the FDM process, residual stresses accumulate in a part during deposition. In this study, an FEA model is used to evaluate the distortions of a part. A parametric study, with three factors and three levels, is performed to evaluate the effects of the deposition parameters on residual stresses and part distortions. Prototype models with larger sizes are fabricated, measured, and compared with the simulations. The simulation results are summarized as follows. First, the scan speed is the most significant factor affecting part distortions, followed by the layer thickness. Second, the road width alone is insignificant. However, the interaction between the road width and the layer thickness is significant as well. Third, there are other two-way and three-way interactions that are of secondary significance. In general, residual stresses in FDM parts increase with the layer thickness. Residual stresses also increase with the road width, but to a lesser extent, although largely affected by the layer thickness. The FDM part distortions from the experiment show a similar trend as concluded in the simulations, but without quantitative correlation. <s> BIB004 </s> A Systematic Survey of FDM Process Parameter Optimization and Their Influence on Part Characteristics <s> 218 <s> Fused deposition modelling (FDM) is a fast growing rapid prototyping (RP) technology due to its ability to build functional parts having complex geometrical shapes in reasonable build time. The dimensional accuracy, surface roughness, mechanical strength and above all functionality of built parts are dependent on many process variables and their settings. In this study, five important process parameters such as layer thickness, orientation, raster angle, raster width and air gap have been considered to study their effects on three responses viz., tensile, flexural and impact strength of test specimen. Experiments have been conducted using central composite design (CCD) and empirical models relating each response and process parameters have been developed. The models are validated using analysis of variance (ANOVA). Finally, bacterial foraging technique is used to suggest theoretical combination of parameter settings to achieve good strength simultaneously for all responses. <s> BIB005 </s> A Systematic Survey of FDM Process Parameter Optimization and Their Influence on Part Characteristics <s> 218 <s> Fused deposition modeling (FDM) has evolved as one of the fastest growing layer manufacturing (LM) technology because of its capability to build even functional plastic parts with geometrical complexity in a reasonable time period. The quality of the production process depends on various process parameters, the most important of them being layer thickness (h), raster angle (θ), orientation (φ), contour width (c) and part raster width (w). In the present study, the influence of these parameters on two process quality parameters, namely, build time and the support material volume are studied on a rotational part modeled on a FDM 200mc machine. A 25 full factorial Design of Experiments (DOE) methodology was employed and the results for build time and support material volume of the 32 experiments were analyzed using Design Expert®. Analysis of variance (ANOVA) was done and based on the ANOVA results the model equation for the two quality parameters in both coded and original factors has been developed. Comments on the results obtained and interaction effects are included at the end of the paper. <s> BIB006 </s> A Systematic Survey of FDM Process Parameter Optimization and Their Influence on Part Characteristics <s> 218 <s> Abstract Fused deposition modelling (FDM) is gaining distinct advantage in manufacturing industries because of its ability to manufacture parts with complex shapes without any tooling requirement and human interface. The properties of FDM built parts exhibit high dependence on process parameters and can be improved by setting parameters at suitable levels. Anisotropic and brittle nature of build part makes it important to study the effect of process parameters to the resistance to compressive loading for enhancing service life of functional parts. Hence, the present work focuses on extensive study to understand the effect of five important parameters such as layer thickness, part build orientation, raster angle, raster width and air gap on the compressive stress of test specimen. The study not only provides insight into complex dependency of compressive stress on process parameters but also develops a statistically validated predictive equation. The equation is used to find optimal parameter setting through quantum-behaved particle swarm optimization (QPSO). As FDM process is a highly complex one and process parameters influence the responses in a non linear manner, compressive stress is predicted using artificial neural network (ANN) and is compared with predictive equation. <s> BIB007 </s> A Systematic Survey of FDM Process Parameter Optimization and Their Influence on Part Characteristics <s> 218 <s> This paper presents the research done to determine the functional relationship between process parameters and tensile strength for the fused deposition modelling (FDM) process using the group method for data modelling for prediction purposes. An initial test was carried out to determine whether part orientation and raster angle variations affect the tensile strength. It was found that both process parameters affect tensile strength response. Further experimentations were carried out in which the process parameters considered were part orientation, raster angle, raster width and air gap. The process parameters and the experimental results were submitted to the group method of data handling (GMDH), resulting in predicted output, in which the predicted output values were found to correlate very closely with the measured values. Using differential evolution (DE), optimal process parameters have been found to achieve good strength simultaneously for the response. The mathematical model of the response of the tensile strength with respect to the process parameters comprising part orientation, raster angle, raster width and air gap has been developed based on GMDH, and it has been found that the functionality of the additive manufacturing part produced is improved by optimizing the process parameters. The results obtained are very promising, and hence, the approach presented in this paper has practical application for the design and manufacture of parts using additive manufacturing technologies. <s> BIB008 </s> A Systematic Survey of FDM Process Parameter Optimization and Their Influence on Part Characteristics <s> 218 <s> Fused deposition modeling (FDM) is gaining distinct advantages because of its ability to fabricate the 3D physical prototypes without the restrictions of geometric complexities, while when it comes to accuracy and efficiency, the advantages of FDM is not distinct, and so how to improve them is worthy of study. Focusing on process parameter optimization, such parameters as line width compensation, extrusion velocity, filling velocity, and layer thickness are selected as control factors, input variables, and dimensional error, warp deformation, and built time are selected as output responses, evaluation indexes. Experiment design is assigned according to uniform experiment design, and then the three output responses are converted with fuzzy inference system to a single comprehensive response. The relation between the comprehensive response and the four input variables is derived with second-order response surface methodology, the correctness of which is further validated with artificial neural network. Fitness function is created using penalty function and is solved with genetic algorithm toolbox in Matlab software. With confirmation test, the results are obtained preferring to the results of the experiment 1 with the best comprehensive response among the 17 experiment runs, which confirms that the proposed approach in this study can effectively improve accuracy and efficiency in the FDM process. <s> BIB009 </s> A Systematic Survey of FDM Process Parameter Optimization and Their Influence on Part Characteristics <s> 218 <s> In fused deposition modeling (FDM) additive manufacturing process, it is often difficult to determine the actual levels of process parameters in order to achieve the best dynamic mechanical properties of FDM manufactured part. This is mainly due to the large number of FDM parameters and a high degree of interaction between the parameters affecting such properties. This requires a large number of experiments to be determined. This paper presents a study on the influence of six FDM process parameters (layer thickness, air gap, raster angle, build orientation, road width, and number of contours) on the dynamic mechanical properties of the FDM manufactured parts using the fraction factorial design. The most influential parameters were statistically obtained through the analysis of variance (ANOVA) technique, and the results indicate that the layer thickness, the air gap, and the number of contours have the largest impact on dynamic mechanical properties. The optimal parameters for maximum dynamic mechanical properties were found to be layer thickness of 0.3302 mm, air gap of 0.00 mm, raster angle of 0.0°, build orientation of 0.0°, road width of 0.4572 mm, and 10 contours. Finally, a confirmation experiment was performed using optimized levels of process parameters, which showed good fit with the estimated values. <s> BIB010 </s> A Systematic Survey of FDM Process Parameter Optimization and Their Influence on Part Characteristics <s> 218 <s> Abstract Fused deposition modeling (FDM) is a growing 3D printing technique widely practiced around the world in various industrial applications because of its ability to create complex 3D objects and geometries. Reduction of build time and feedstock material consumption without compromising the mechanical performance is the major concern in most industrial applications affecting the cost and the functionality of the manufactured part. One of the key issues of FDM process is how to select the correct parameters to reduce the build time and to reduce feedstock material consumption while maintaining high dynamic mechanical properties. In this study, influence of critical FDM parameters—layer thickness, air gap, raster angle, build orientation, road width, and number of contours—are studied using Q-optimal response surface methodology. Their effects on build time, feedstock material consumption and dynamic flexural modulus are critically examined. Mathematical models have been formulated to develop a functional relationship between the processing conditions and the process quality characteristics. Analysis of variance (ANOVA) technique was employed to check the adequacy and significance of mathematical models. Moreover, the optimal setting of process parameters was determined. A confirmation test was also conducted in order to verify the developed models and the optimal settings. The results show that Q-optimal design is a very promising method in FDM process parameter optimization. The results also confirm the adequacy of the developed models. <s> BIB011 </s> A Systematic Survey of FDM Process Parameter Optimization and Their Influence on Part Characteristics <s> 218 <s> Abstract Fused deposition modelling is a rapidly growing additive manufacturing technology due to its ability to build functional parts having complex geometries. The mechanical properties of a built part depend on several process parameters. The aim of this study is to characterize the effect of build orientation, layer thickness and feed rate on the mechanical performance of PLA samples manufactured with a low cost 3D printer. Tensile and three-point bending tests are carried out to determine the mechanical response of the printed specimens. Due to the layer-by-layer process, 3D printed samples exhibit anisotropic behaviour. Upright orientation shows the lowest mechanical properties. On the other hand, on-edge and flat orientation show the highest strength and stiffness. From a layer thickness and feed rate point of view, it is observed that ductility decreases as layer thickness and feed rate increase. In addition, the mechanical properties increase as layer thickness increases and decrease as the feed rate increases for the upright orientation. However, the variations in mechanical properties with layer thickness and feed rate are of slight significance for on-edge and flat orientations, except in the particular case of low layer thickness. Finally, the practicality of the results is assessed by testing an evaluation structure. <s> BIB012
Wang et al. BIB003 studied the influence of six process parameters on dimensional accuracy. The In many papers, different statistical tools such as full factorial design BIB008 BIB006 , fractional factorial design BIB010 BIB001 , and face-centered central composite design (FCCCD) BIB005 BIB004 were used to gain maximum information from a smaller number of experiments. As another approach, optimum levels of parameters for analyzing part characteristics were determined based on experimental results. In some papers, such as Mohamed et al. BIB011 and Chacón et al. BIB012 , various mathematical models were developed to show a relationship between process parameters and part quality. Peng et al. BIB009 and Rayegani et al. BIB008 worked on optimizing mathematical models of part characteristics to determine optimal levels of process parameters. There were also approaches that looked into characteristics of more than one part that were optimized simultaneously. For this, various heuristic optimization algorithms, for example, quantum-behaved particle swarm optimization (QPSO) BIB007 , non-dominated sorting genetic algorithm II (NSGA-II)  , differential evolution (DE) BIB008 , and genetic algorithm (GA) BIB002 , were used. In the following subsections, a systematic summary of research analyzing each FDM printed part's quality characteristic is given.