Dimensional Errors Research Articles

Precise machining based on Ritz non-uniform allowances for titanium blade fabricated by selective laser melting

Selective laser melting (SLM) is an increasingly concerned trend in Ti-6Al-4V blade manufacturing, while the SLMed Ti-6Al-4V blade cannot be used directly because of poor surface integrity and high residual stresses. Precise machining after SLM is a feasible solution but also a challenge. The low rigidity of the blade will lead to deformation when machining. The deformation can lead to surface error and may make defect parts. Two-step machining processes to address the problems were proposed in this paper. First, a non-uniform allowances distribution was allocated and optimized in semi-finishing based on Ritz solution to elastic deformation. The blade was simplified as a cantilever thin plate with various thicknesses, and the thicknesses of finishing allowances were designed and optimized on the premise of ensuring the thin-wall stiffness of the blade, so as to realize the design of Ritz non-uniform allowances. Then, finishing machining was conducted to achieve precise parts. A blade deformation model was established to evaluate part distortions with cutting force moving and changing. Finite element analysis (FEA) and experimental validation in ball-end milling of a blade were conducted. FEA results and experimental results showed dimensional errors have been reduced up to 50%. Further surface tests demonstrated that the mean surface roughness reduced from 7.88 to 0.815 μm. And the residual surface stresses of the SLM samples changed after semi-finishing machining due to the residual stresses relaxation and redistribution. The results demonstrated that the proposed method enhanced the surface quality of the blade fabricated by SLM.

Distortion discrepancy of large-scale components in electron beam melting processes

Amongst many factors that hinder the industry from adopting additive manufacturing technology, dimensional printing error and thermal distortion are crucial, especially for large-scale components (length > 100 mm). Although residual stress in an electron-beam melting (EBM) printed part is relatively low, part distortion cannot be neglected in quality control and post-processing. To investigate distortion rules of EBM parts along the X and Y direction of the build plate, a series of L shape beams, with a length of 130 mm in both X and Y, were designed, printed, and characterized. Both 3D scanning and multi-functional coordinate-measuring machine (CMM) were used to measure designed hexagonal marks with a 10 mm interval along part gauge length. The dimensional error between designed and printed parts was calculated and analyzed. Results showed that the beams shrank orthotopically in terms of X and Y directions in discrepant rules. In the X direction, total shrinkage was around 0.7 %, accumulating with a stable increment. While in the Y direction, the shrinkage was indistinctive without apparent accumulation. We observed a slight wall thickness effect on shrinkage non-uniform accumulation in the X direction. Thin wall structures (T = 1 mm and 2.5 mm) distorted more at the beginning 40 mm of the part length from the origin point than the rest to the rear end. On the other hand, thick wall (T = 10 mm) distorted more at the rear end.

Evaluation of dimensional accuracy of 3D printed mandibular model using two different additive manufacturing techniques based on ultralow dose multislice computed tomography scan data: A diagnostic accuracy study

Aim: To compare and validate the dimensional accuracy of two of the most popular 3D printing techniques: highly professional stereolithography (SLA) and low-cost fused deposition modeling (FDM), using 3D printed mandibular models based on low-dose multislice computed tomography (MSCT) scan data. Materials and Methods: In order to compare SLA and FDM, the mandibular model was scanned using an ultralow dose MSCT scanner. The scanner generated DICOM file which was converted to STL format. The digital 3D model was printed seven times with each of the printing techniques: SLA and FDM. Ten linear measurements of the printed models were compared with the reference model using a digital caliper. Differences between measurement were analyzed and compared for trueness and accuracy of both FDM and SLA printers. Results: The statistical analysis showed a statistically significant difference in the dimensional error of both techniques in comparison to the reference model, in which the mean relative difference is 0.30% and −0.97% and the mean absolute difference is 0.13 mm and −0.44 mm for SLA and FDM, respectively. Upon comparing the two utilized 3D printing techniques, the trueness of both SLA and FDM showed no statistical or clinically significant difference in the dimensional error, with the mean relative difference and the mean absolute difference of SLA being lower than those of FDM. Conclusion: These results suggest that both printers can be used safely in dental practice and that a low-cost FDM printer can provide an accuracy level comparable to the professional SLA printer.

Dimensional accuracy of medical models of the skull produced by three-dimensional printing technology by advanced morphometric analysis

Introduction: Three-dimensional (3D) printing creates a design of an object using software, and the process involves by converting the digital files with a 3D data using the computer-aided design into a physical model. The aim of the study was to investigate the accuracy of human printed 3D skull models from computed tomography (CT) scan data via a desktop 3D printer, which uses fused deposition modeling (FDM) technology. Material and Methods: Human anatomical cadaver skulls were CT scanned in 128-slice CT scanner with a slice thickness of 0.625 mm. The obtained digital imaging and communications in medicine files were converted to 3D standard tessellation language (STL) format by using MIMICS v10.0 software (Materialise, Leuven, Belgium) program. The 3D skull model was printed using a Creatbot DX desktop 3D FDM printer. The skull model was fabricated using polylactic acid filament with the nozzle diameter of 0.4 mm and the resolution of the machine was maintained at 0.05 mm. The accuracy was estimated by comparing the morphometric parameters measured in the 3D-printed skull with that of cadaver skull and with CT images to ensure high accuracy of the printed skull. Fourteen morphometric parameters were measured in base and cranial fossa of the skull based on its surgical importance. Results: Analysis of measurements by inferential statistical analysis of variance for all three groups showed that the 3D skull models were highly accurate. Reliability was established by interobserver correlation for measurements on cadaver skull and the 3D skulls. Dimensional error was calculated, which showed that the errors between three groups were minimal and the skulls were highly reproducible. Discussion and Conclusion: The current research concludes that a 3D desktop printer using FDM technology can be used to obtain accurate and reliable anatomical models with negligible dimensional error.

Assessment of dimensional accuracy of 3D printed part using resin 3D printing technique

Resin 3-Dimensional (3D) printing technology is known for complex parts with fine features and accurate dimensions for its high quality, high-resolution. The ability to print dimensionally accurate parts, depends on equipment, materials and slicer, few of which are layer height, orientation, and exposure time. The modern technology allows designers to visualizing the component before it is manufactured, which reduces the design's challenges. Manufacturers can take this advantage of 3D printing to manufacture the components directly, but accuracy and precision must be maintained to the close extent. The printed part is not completely cured during printing process and it requires post curing. Here, Ultra Violet (UV) laser light adopted for post curing, which causes dimensional inaccuracies, it may lead to clearance and fits problem. In general, 3D printed objects are prone to size inaccuracies, the most common of which are variations in the linear dimensions and hole diameter. The consequences of these two types of faults on the dimensional accuracy of a typical component were explored. This article shows the experimental results for dimensional correctness of post-cured parts printed using resin 3D printing process. The study aimed in presenting the errors associated with the dimensional accuracy along with the interaction effects of process parameters using Design of Experiments. The contour plots and pareto charts are also presented, in order to understanding the effect of factors and their levels on output measures and most influencing factors for dimensional accuracy (DA) respectively. Based on the findings, it was observed that the dimensional errors are causing due to shape and size changes in the part, many times the larger error bars are observed for internal and external diameters than the liner dimensions. From the interaction plots it can be concluded that layer height of 0.06 mm is always referring to low deviation for all the output measures along with the exposure time of 3 and 5 sec and 00 and 150 x-orientation.

Optimization of hole quality parameters using TOPSIS method in drilling of GFRP composite

The attractive mechanical properties and light weight to strength ratio Glass Fiber Reinforced Plastic (GFRP) composites are preferred in automobile and aerospace industries. Drilling process is one of the basic and important manufacturing processes. Drilling of GFRP and its issues with hole quality are fiber crack, roughness of surface, dimensional error and delamination. In this work, the influence of three different types of drills (Slot type, twist type and brad type) and process parameters (feed rate and machining speed) on hole quality error is analyzed. Hole quality parameters, chosen are roundness error, roughness of the machined area, delamination factor and diameter deviation. Simultaneous optimization of multiple objectives is difficult task. Order Preference Technique by Similarity to Ideal Solution named as TOPSIS is used for optimizing the performance criteria and minimize the hole quality error during drilling of GFRP composite. The result revealed that spur type drill with higher range of spindle speed was provided less error in the drilled holes. Also, TOPSIS procedure has minimum computational time because of its less computational steps and highly preferrable for various decision-making problems in manufacturing industry. Hole quality error is directly influencing the assembly accuracy and its minimization is important one.

Robust and Fast CAD Model Tessellation for Inspection

The digital manufacturing deviation inspection can be used to assess the dimension, form, and position errors, which is more efficient, more consistent, and more robust than manual inspection. CAD models are used as the nominal data and compared with the scanned data of parts to obtain manufacturing errors. CAD model tessellation is a pivotal step in deviation inspection, which directly determines the reliability of analytical results. It requires that the generated triangle mesh has dense vertices, high approximation accuracy, and consistent orientation. A single surface patch tessellation method is proposed, and the adaptive quadtree is first constructed to divide the domain into small spatial grids in the parameter space of the patch; then, a clip-based method is presented to triangulate boundary grids, and inner grids could be triangulated by the constrained Delaunay triangulation method. Furthermore, the mesh patches should be spliced and reoriented consistently, which is very important for deviation analysis. To solve this problem, a robust gap healing method based on merging boundary points of patches is developed, so that all boundary vertices of adjacent patches could completely coincide along the common edges, and all mesh patches would be stitched into a complete mesh without gaps. Finally, the face normal of mesh is adjusted to obtain a consistent orientation. Experiments on industrial CAD models demonstrate that the proposed method could realize faster and more robust mesh generation than the state-of-the-art approaches, including three commercial and two open-source software.

3D Huygens Principle Based Microwave Imaging Through MammoWave Device: Validation Through Phantoms

This work focuses on developing a 3D microwave imaging (MWI) algorithm based on Huygens principle (HP). Specifically, a novel, fast MWI device (MammoWave) has been presented and exploited for its capabilities of extending image reconstruction from 2D to 3D. For this purpose, dedicated phantoms containing 3D structured inclusion have been prepared with mixtures having different dielectric properties. Phantom measurements have been performed at multiple planes along the z-axis by simultaneously changing the transmitter and receiver antenna height via the graphic user interface (GUI) integrated with MammoWave. We have recorded the complex S21 multi-quote data at multiple planes along the z-axis. The complex multidimensional raw data has been processed via an enhanced HP based image algorithm for 3D image reconstruction. This paper demonstrates the successful detection and 3D visualization of the inclusion with varying dimensions at multiple planes/cross-sections along the z-axis with a dimensional error lower than 7.5%. Moreover, the paper shows successful detection and 3D visualization of the inclusion in a skull-mimicking phantom having a cylindrically shaped inclusion, with the location of the detected inclusion in agreement with the experimental setup. Additionally, the localization of a 3D structured spherical inclusion has been shown in a more complex scenario using a 3-layer cylindrically shaped phantom, along with the corresponding 3D image reconstruction and visualization.

Human-Computer Interaction in Translation Activity: Fluency of Machine Translation

Digitalization is one of the key distinctive features of modern environment and social life. Nowadays more and more functions are transferred to the artificial mind. How effective is the replacement of human activity with computer activity? In the given article, this problem is solved by an example of integration of digital technologies into translation activities. It this paper, emphasis is placed on the quality of machine translation (MT) output of legal texts in the language pair English - Slovak. It studies a Criminal Code formulated in the Slovak language which was translated by a human translator into English and consequently via machine translation system Google Translate (GT) back into Slovak. The back-translation - translation of a translated text back into its original language - as a quality assessment tool to detect discrepancies, mistranslations and inevitable differences between the source text and the target text was used. The quality of MT output was evaluated according to Multidimensional Quality Metrics (MQM) standards with the focus on the dimension of Fluency. The multiple comparisons were applied to determine which issues (errors) in Fluency dimension differ from the others. A statistically significant difference is noticed between Agreement and other issues, as well as between Ambiguity and other issues. The errors in Agreement are related to the differences between the languages: English is considered mostly an analytic language, Slovak represents a synthetic language. The issues in the Ambiguity dimension correlate with the type of the text being examined, since legal texts are characterized by relatively complicated wording and numerous terms; moreover, accuracy and unambiguity need to be preserved. Generally, the MT output is able to provide users with basic information about the text. On the other hand, most of the segments need revision and/or correction; in such cases, human intervention and post-editing is necessary.

Direct ink writing of cordierite ceramics with low thermal expansion coefficient

Since the application of cordierite ceramics is limited by the disadvantages of traditional preparation techniques, 3D printing technology provides the only choice for the rapid preparation of cordierite ceramics with highly complex structures. In this work, the fabrication of cordierite ceramics with complex structures was achieved by direct ink writing. The near-net-shape of cordierite ceramics was realized by the volume expansion caused by the phase transformation. A cordierite ceramic with an average shrinkage rate of 1.58 % was obtained at 1400 °C. The low shrinkage avoids design and manufacturing procedures carried out for dimensional and alignment errors. In addition, the coefficient of thermal expansion was as low as 1.69 × 10−6 °C−1. The effect of configuration on the thermal behavior of cordierite ceramics is understood by analyzing the phase composition and microstructure. The cordierites ink reported in this work offers additional possibilities for the production of novel complex structures.

Analysis and Optimization of Dimensional Accuracy and Porosity of High Impact Polystyrene Material Printed by FDM Process: PSO, JAYA, Rao, and Bald Eagle Search Algorithms.

High impact polystyrene (HIPS) material is widely used for low-strength structural applications. To ensure proper function, dimensional accuracy and porosity are at the forefront of industrial relevance. The dimensional accuracy cylindricity error (CE) and porosity of printed parts are influenced mainly by the control variables (layer thickness, shell thickness, infill density, print speed of the fused deposition modeling (FDM) process). In this study, a central composite design (CCD) matrix was used to perform experiments and analyze the complete insight information of the process (control variables influence on CE and porosity of FDM parts). Shell thickness for CE and infill density for porosity were identified as the most significant factors. Layer thickness interaction with shell thickness, infill density (except for CE), and print speed were found to be significant for both outputs. The interaction factors, i.e., shell thickness and infill density, were insignificant (negligible effect) for both outputs. The models developed produced a better fit for regression with an R2 equal to 94.56% for CE, and 99.10% for porosity, respectively. Four algorithms (bald eagle search optimization (BES), particle swarm optimization (PSO), RAO-3, and JAYA) were applied to determine optimal FDM conditions while examining six case studies (sets of weights assigned for porosity and CE) focused on minimizing both CE and porosity. BES and RAO-3 algorithms determined optimal conditions (layer thickness: 0.22 mm; shell thickness: 2 mm; infill density: 100%; print speed: 30 mm/s) at a reduced computation time equal to 0.007 s, differing from JAYA and PSO, which resulted in an experimental CE of 0.1215 mm and 2.5% of porosity in printed parts. Consequently, BES and RAO-3 algorithms are efficient tools for the optimization of FDM parts.

A low-g omnidirectional MEMS inertial switch with load direction identification

In order to solve the problem that the low-g omnidirectional MEMS inertial switches cannot recognize the load direction, a nickel omnidirectional MEMS inertial switch with identifiable load direction and uniform in-plane threshold distribution was designed. The switch is mainly composed of a spring–mass system, four independent flexible radial electrodes and an axial electrode. The function of identifying the direction of acceleration is realized by detecting the closed states of different electrodes. According to the design results of MEMS inertial switch, the dynamic performance of the switch was analyzed by ANSYS software. The results show that the designed switch meets the functional requirements of load direction identification. Based on UV-LIGA multilayer photolithography, the nickel MEMS inertial switch was fabricated on a steel substrate. In the process of fabrication, the line width compensation method was used to reduce the dimensional error caused by swelling phenomenon and removal process of the photoresist. What's more, the thickness compensation method was used to reduce the process error caused by flattening treatment. The overall dimension of the switch is 5300 × 5300 × 270 μm and the smallest line-width is 20 μm. Ultimately, the fabricated switch was tested by the centrifuge device and dropping hammer in XOY plane and Z-axis direction. The dynamic threshold of the switch is between 7.9 and 11.3 g, and the response time in each direction is less than 2 ms. The switch can recognize the direction of acceleration in XOY plane and Z-axis. The switch has an excellent anti-overload performance.

Modeling of the Influence of Input AM Parameters on Dimensional Error and Form Errors in PLA Parts Printed with FFF Technology.

As is widely known, additive manufacturing (AM) allows very complex parts to be manufactured with porous structures at a relatively low cost and in relatively low manufacturing times. However, it is necessary to determine in a precise way the input values that allow better results to be obtained in terms of microgeometry, form errors, and dimensional error. In an earlier work, the influence of the process parameters on surface roughness obtained in fused filament fabrication (FFF) processes was analyzed. This present study focuses on form errors as well as on dimensional error of hemispherical cups, with a similar shape to that of the acetabular cup of hip prostheses. The specimens were 3D printed in polylactic acid (PLA). Process variables are nozzle diameter, temperature, layer height, print speed, and extrusion multiplier. Their influence on roundness, concentricity, and dimensional error is considered. To do this, adaptive neuro-fuzzy inference systems (ANFIS) models were used. It was observed that dimensional error, roundness, and concentricity depend mainly on the nozzle diameter and on layer height. Moreover, high nozzle diameter of 0.6 mm and high layer height of 0.3 mm are not recommended. A desirability function was employed along with the ANFIS models in order to determine the optimal manufacturing conditions. The main aim of the multi-objective optimization study was to minimize average surface roughness (Ra) and roundness, while dimensional error was kept within the interval . When the simultaneous optimization of both the internal and the external surface of the parts is performed, it is recommended that a nozzle diameter of 0.4 mm be used, to have a temperature of 197 °C, a layer height of 0.1 mm, a print speed of 42 mm/s, and extrusion multiplier of 94.8%. This study will help to determine the influence of the process parameters on the quality of the manufactured parts.

Folding Responses of Origami-Inspired Structures Connected by Groove Compliant Joints

Abstract The compliant mechanism can effectively reduce friction and eliminate the joint gap during the motion. The performances of compliant joints directly determine the overall behavior of mechanisms. In this paper, a new type of compliant joint is designed based on weakened creases and elastic–plastic materials. Parametric analysis is carried out to investigate the influence of compliant joint details on its structural performances by combining finite element methods and experiments. The compliant joints are evaluated and optimized regarding the rotational stiffness and plastic strain magnitude of the slot region. In addition, the optimized compliant joint is introduced to the Miura unit. The configuration analysis is performed for the folding, unfolding, and releasing processes, which are further extended to the discussion on the cyclic performance of the compliant joint. It can be found that the origami-inspired structures can maintain a high residual stiffness after the release process. Finally, the methodology is applied to the Miura origami array embedded with the designed compliant joint. The results of dimensional errors and stress distributions can show that the design of the compliant joints can effectively control the configuration of the Miura origami array. The principle in this paper can open a new avenue to design and utilize the compliant in the deployable or morphing structures.

Study of a Multi-Fusion Positioning System Based on Beidou Indoor Inertial Navigation

This article proposes an indoor combined positioning terminal based on Beidou pseudofiles and micro-inertial navigation sensors. Through the built-in Beidou pseudo lite positioning IP soft core, it can receive and analyse Beidou satellite signals. The article creates BDS ground inertial positioning data receiving hardware; performs inertial positioning data primary information identification authentication on the inertial data received by the hardware; performs multi-inertial data fusion estimation calculation on inertial positioning data after authentication, reduces the dimensional error value, and completes the proposed system Design. The program makes full use of the data resources of the existing airborne equipment, does not need to transmit radio signals, and the user capacity is not limited, which is suitable for highly dynamic users. Through simulation and sports car test, it is proved that the scheme is feasible.

Damage characteristics of coal under different loading modes based on CT three-dimensional reconstruction

Due to the heterogeneous characteristics of coal materials, it is difficult to carry out repetitive tests and quantitative analysis of internal damage of coal. Therefore, the damage characteristics of coal under uniaxial and true triaxial loading was studied by numerical simulation based on 3D reconstruction modeling, and the corresponding mechanics experiment was used for auxiliary parameter validation. Firstly, the CT scanning system was used to scan the coal specimen, and the Otsu method was used to segment the original CT images to extract the three-dimensional fracture network and the distribution characteristics of mineral components. Secondly, the internal fracture and mineral distribution network model of the coal was reconstructed and imported into FLAC3D for modeling, and the numerical model was validated by fractal geometry method. The average error of fractal dimension between the original CT image and the corresponding numerical model is 1.422%, showing that the numerical model is basically consistent with the CT image of the coal, and the numerical model could reflect the distribution characteristics of the internal fractures and mineral components of the coal. Then, the basic mechanical parameters and acoustic emission (AE) response characteristics of CT reconstructed coal samples were obtained. And the mechanical parameters of the numerical model were calibrated. It can be concluded that the stress–strain curve of the coal is basically consistent with that of the numerical model, and the AE response characteristics of the coal are basically consistent with the evolution of the plastic zone of the numerical simulation, indicating that the numerical model and parameters are reasonable in this work. Moreover, the damage variable evolution of coal specimen in uniaxial compression and true triaxial loading was studied. Finally, the damage equation of coal under uniaxial compression and the relationship between damage variable and body strain energy under true triaxial loading were established.

Visualization Of Thermal Distribution During Machining of Dental Implants

Dental implants used are usually metallic. One of the most widely used materials for the same is Titanium-based alloy like Ti-6Al-4V, which suffers difficulty processing and machining due to its thermo-physical properties. The thermo-physical property of the material plays a significant role in the biocompatibility and safety to use them as dental implants. Due to its hardness and difficult-to-machine characteristics, a large amount of heat gets generated while machining, creating dimensional error. Hence before assembly of parts, they must be processed so that stress deformation of the assembly due to heat can be avoided. During machining of Ti-6Al-4V, the cooling strategy needs prior information on the thermal field, and hence, the distribution of temperature in the material is an essential domain to study. To understand the thermal distribution in the material during machining, 3-dimensional heat diffusion equations have been solved using a Finite Difference scheme coupled with the Liebmann method to generate the thermal distribution in the material. An efficient parallelized code for the same has been written in MATLAB and utilized in this numerical study. This study reveals the variation of the temperature gradient with time and space, all along with the three orthogonal directions, which will be helpful for the scientists, engineers, and surgeons to ascertain the sustainability [1, 2], suitability, and longevity of the implants.

Sub-regional thermal error compensation modeling for CNC machine tool worktables

For computer numerical control (CNC) machine tools, thermal error is currently compensated according to a single fixed point on the worktable. When the worktable is in motion, the thermal error obviously differs across the worktable due to manufacturing, assembly, and other factors from driving and supporting devices. This causes the thermal error compensation by the single-point (SP) method to have great uncertainty for the whole worktable. To solve this problem, this paper proposes a sub-regional (SR) method to compensate for the thermal error of a worktable. The SR method divides the worktable into different regions and establishes a thermal error compensation model for each region, which are then combined to compensate for the thermal error of the whole worktable. The influence of the number of regions on the compensation effect of the SR method was analyzed theoretically and validated experimentally to provide a basis for determining a reasonable number of regions. The prediction effects of the SR method were compared with the SP method. And the compensation effects of the SR method were compared with a two dimensional thermal error map compensation method. The experimental results showed that the SR method has high prediction accuracy and stability and has better compensation effect in practical application for the whole worktable.

Experimental measuring of printing speed in FDM

Fused Deposition Modeling (FDM) technology, based on material extrusion, helps additively manufacture, using cheap printers, stable mechanical parts in different materials. The dimensional deviations and staircase effect are the main drawbacks of this approach and limit its use to prototypes. The linear interpolation used to define the hot-end movements is responsible for continuous speed changes along the tool-path, contributing to dimensional and surface errors. In that sense, the study of the speed profile can help to improve the process. This work explains two printing speed estimation approaches an out-process measurement method, which estimates the average speed as a function of the interpolation segment length and direction, and an in-process method based on encoder measurements. We applied these solutions and an analytical approximation based on a trapezoidal speed profile to a printed 3D Archimedean spiral. All approaches detect abrupt speed changes, potential candidates to produce extrusion-movement synchronization problems, and, therefore, part errors.

Down-facing surfaces in laser powder bed fusion of Ti6Al4V: Effect of dross formation on dimensional accuracy and surface texture

Down-facing surfaces are one of the most challenging features in metal parts produced by laser powder bed fusion (LPBF). A combination of reasons, primary of which are residual stresses and overheating cause these features to have the worst surface finish and dimensional accuracy of all LPBF surfaces. In order to examine this phenomenon, a Design of Experiments (DoE) study is conducted for three different inclination angles, namely 45°, 35° and 25° and for two different layer thicknesses of 60 µm and 90 µm. The results from the DoE are used to establish quadratic regression equations that can be used to predict the quality marks of surface roughness and the relative dimensional error.This fundamental investigation helps to explain the reasons for the major defects in down-facing surfaces of parts produced with Ti-6AL-4 V material, namely the dross formation and attempts to improve the predictability of quality within the region. Further to the establishment of the quadratic equations, a discussion is conducted on the thermomechanical processes involved in the mechanism of dross formation and explanations are given on the reasons behind the observed physical phenomena. The trend of the propagation of (Root Mean Square) RMS Surface roughness (Sq) and the relative dimensional error with respect to the Volumetric Energy Density (VED) is discussed in detail. The respective quadratic equations are then tested by a second round of validation prints, and the results confirm the feasibility of the developed quadratic models to accurately predict process outcomes especially when operating near the suggested optimal printing zones. The high roughness of low VED printing is attributed to the formation of ‘inverse mushroom’ structures, and the low roughness of high VED surface is attributed to the formation of large flat regions formed as adjacent meltpools that can fuse together at various locations.