Hybrid Manufacturing Technology Research Articles

Performance-driven 3D printing of continuous curved carbon fibre reinforced polymer composites: A preliminary numerical study

This paper presents a new concept to place continuous curved fibres for carbon fibre reinforced polymer (CFRP) composites, which can be fulfilled by potential additive or hybrid manufacturing technology. Based on the loading condition, principal stress trajectories are generated through finite element analysis (FEA) and used as the guidance for the placement paths of carbon fibres. Three numerical cases including an open-hole single ply lamina under uniaxial tension and open-hole cross-ply laminate under biaxial tension and normal pressure are studied and compared with traditional reinforced composites with unidirectional fibres. The modelling results show that the stress concentration in both fibre and matrix are reduced significantly by the curved fibre placement and the stiffness of CFRP composites have been improved. This concept of performance-driven optimization method could lead to a useful tool for the design of future 3D printing process for fibre reinforced composites.

Densification, surface morphology, microstructure and mechanical properties of 316L fabricated by hybrid manufacturing

In recent years, additive manufacturing (AM) has been developed for industrial applications due to its superior performance, such as in building complex parts, which are especially difficult to build when using traditional methods. However, the surface quality, and dimensional and geometric accuracies of AM parts do not exceed conventionally machined parts, which hinders the AM applications. To overcome these limitations, hybrid manufacturing (HM) technology, which combines AM and subtractive manufacturing (SM) technologies in a single workstation has received a great deal of attention in academic and industrial circles to enhance material utilization, part complexity and quality control when producing functional parts. In this paper, we present research achievements using ANSI 316L stainless steel parts via the HM process and analysis of its surface morphology and microstructural characteristics, densification behaviour and mechanical properties. Specimens before and after heat treatment were analysed and compared. The study also dealt with material characterization via the Archimedes method, scanning electron microscopy (SEM), X-ray polycrystalline diffractometer (XRD) and tensile measurements. This study provides a valuable guide to determining the effectiveness of the HM process and its use when producing engineering parts.

Automated process planning for hybrid manufacturing

Hybrid manufacturing (HM) technologies combine additive and subtractive manufacturing (AM/SM) capabilities, leveraging AM’s strengths in fabricating complex geometries and SM’s precision and quality to produce finished parts. We present a systematic approach to automated computer-aided process planning (CAPP) for HM that can identify non-trivial, qualitatively distinct, and cost-optimal combinations of AM/SM modalities. A multimodal HM process plan is represented by a finite Boolean expression of AM and SM manufacturing primitives, such that the expression evaluates to an ‘as-manufactured’ artifact. We show that primitives that respect spatial constraints such as accessibility and collision avoidance may be constructed by solving inverse configuration space problems on the ‘as-designed’ artifact and manufacturing instruments. The primitives generate a finite Boolean algebra (FBA) that enumerates the entire search space for planning. The FBA’s canonical intersection terms (i.e., ‘atoms’) provide the complete domain decomposition to reframe manufacturability analysis and process planning into purely symbolic reasoning, once a subcollection of atoms is found to be interchangeable with the design target. We therefore show that geometric and spatial reasoning can be decoupled from logic and combinatorial search required to find process plans. The approach subsumes unimodal (all-AM or all-SM) process planning as special cases. We demonstrate the practical potency of our framework and its computational efficiency when applied to process planning of complex 3D parts with dramatically different AM and SM instruments.

Analysis of the capability of the national measurement standards of Ukraine for assurance of traceability in the field of additive manufacturing

The national measurement standards from the point of view of traceability of the results of measurement in additive manufacturing in Ukraine are considered in the paper. The metrological characteristics of the national primary measurement standards in the field of geometric, temperature, optical-physical and time-frequency measurements, which took part in international comparisons within COOMET projects, are presented. The accurate geometric, temperature, optical-physical and time-frequency measurements are the key ones in controlling the quality of additive manufacturing. The use of advanced CAD/CAE/CAM systems allows to simulate the process of additive manufacturing at each stage. The problem with the classification methods is that some processes have a complex (hybrid) manufacturing technology, for example, sintering is combined with AM or the use of laser welding, followed by processing on a milling or turning machine. In accordance with the areas of the technology of additive manufacturing, the ways of improving the national measurement standards of Ukraine for the growing needs of metrology of additive manufacturing are considered.

An Empirical Model for Controlling Characteristics of Micro Channel Machined Using Abrasive Assisted Electrochemical Jet Machining

Metallic micro channels provide functions of fluid feed and heat exchange in fields of fuel cell, MEMS component, micro mold and heat exchanger. Abrasive assisted electrochemical jet machining (AECJM) is a hybrid manufacturing technology coupling erosion and corrosion concurrently to remove metals. The AECJM shows a great potential in machining micro channels at metallic surface. From production point of view, it is highly necessary to control the channel characteristics, e.g. width and depth, during the AECJM operation to meet possible specifications from industries. This paper presents an empirical model to predict width and depth of micro channels machined in stainless steel 304 using AECJM with electrolytic solution of NaNO3, abrasives of Al2O3 and DC working voltage. The empirical model was established on a basis of non-linear regression analysis with process variables of working voltage, abrasive concentration, solution concentration, jet pressure, jet scan speed and jet scan passes. Verified results show that the empirical model can predict channel width and depth with a deviation from -6.3% to 4.4% for most cases before process operation. However, the strategies of determining machining parameters are highly important when applying the empirical model to reach a specific machining target.

Machining of microchannel at SS316 surface using abrasive-assisted electrochemical jet machining

Metallic microchannels are increasingly used in fuel cell, MEMS component, cutter, and micromold due to functions of fluid feed and heat exchange. Abrasive-assisted electrochemical jet machining (AECJM) is a hybrid manufacturing technology coupling erosion and corrosion concurrently to remove metals. It shows a great potential in machining microchannels with complex patterns at metallic surface. The present work explored the feasibility of patterning complex microchannels at SS316 surface using AECJM at a condition of Al2O3 abrasives, NaNO3 solution, and DC potential. A series of microchannels were machined by AECJM to investigate the effects of process conditions on the material removal rate, machining current density, aspect ratio, and surface roughness. The results show that the anodic dissolution dominates material removal in the AECJM of SS316 at present conditions. The material removal rate nonlinearly correlates with machining current density between approximate 3 to 10 A/cm2 due to a nonlinear relationship of current efficiency and current density. It is also shown that the anodic dissolution can be influenced positively or negatively by abrasives impingement due to the synergy of erosion and corrosion. Relatively higher abrasive dose and jet velocity result in a reduction of anodic dissolution and however an increase of abrasive erosion. The experiments of fabricating complex patterns demonstrate that AECJM has a high potential to machine microchannels at SS316 efficiently and economically.

A new algorithm for build time estimation for fused filament fabrication technologies

The manufacture of highly complex and accurate part geometries with reduced costs has led to the emergence of hybrid manufacturing technologies where varied manufacturing operations are carried out in either parallel or serial manner. One such hybrid process being currently developed is the iAtractive process, which combines additive (i.e. fused filament fabrication, which is sometimes called fused deposition modelling. However, the latter term is trademarked by Stratasys Inc. and cannot be used publicly without authorisation from Stratasys) and subtractive (i.e. computer numerical control machining) processes. In the iAtractive process production, operation sequencing of additive and subtractive operations is essential. This requires accurate estimation of production time, in which the fused filament fabrication build time is the determining factor. There have been some estimators developed for fused deposition modelling. However, these estimators are not applicable to hybrid manufacturing, particularly in process planning, which is a vital stage. This article addresses the characteristics of fused filament fabrication technologies and develops a novel and rigorous method for predicting build times. An analytical model was first created to theoretically analyse the factors that affect the part build time and was subsequently used to facilitate the design of test parts and experiments. The experimental results indicate that part volume, interaction of volume and porosity and interaction of height and intermittent factor have significant effects on build times. Finally, the estimation algorithm has been developed, which was subsequently evaluated and validated by applying a wide range of identified influential factors. The major advantage of the new proposed algorithm is its ability to estimate the build time based on simple geometrical parameters of a given part. The key factors that drive the algorithm can be directly obtained from part dimensions/drawings, providing an efficient and accurate way for fused filament fabrication time estimation. Test part evaluations and analysis have clearly demonstrated that estimation errors range from 0.1% to 13.5%, showing the validity, capability and significance of the developed algorithm and its applications to hybrid manufacture.

Improvement in Geometrical Accuracy and Mechanical Property for Arc-Based Additive Manufacturing Using Metamorphic Rolling Mechanism

Additive manufacturing (AM), or 3D printing, is drawing considerable contemporary interest due to its characteristics of high material utilization, great flexibility in product design, and inherent moldless process. Arc-based AM (AAM) is a promising AM method with high deposition rate and favorable buildup quality. Components made by AAM are fabricated through superimposed weld beads deposited from metal wire. Unlike laser-based additive manufacturing, AAM is more difficult to control. Because of the large energy input of the energy source and the liquidity of the melting metal material, bottleneck problems like shrinkage porosity, cracking, residual stresses, and deformation occur. Resultant poor geometrical accuracy and mechanical property keep AAM from industrial application. Especially in the aerospace industry, structural and mechanical property specifications are stringent and critical. This paper presents a novel hybrid manufacturing method by using hot-rolling process to assist the arc welding to solve the above problems. Initially, a miniature metamorphic rolling mechanism (MRM) was developed using metamorphic mechanism theory. Configuration and topology of the MRM can change according to the feature of the components to roll the top and lateral surfaces of the bead. Subsequently, three single-pass multilayer walls were built, respectively, for comparison. The rolled results show significant improvement in geometrical accuracy of the built features. Tensile test results demonstrate improvement in mechanical properties. The improved mechanical properties of rolled specimens are superior to wrought material in travel direction. Microstructure comparisons indicate columnar grains observed in vertical direction and fusion zones were suppressed. Eventually, fabrication of a large-scale aerospace component validates the feasibility of industry application for the hybrid manufacturing technology.

Advanced hybrid welding and manufacturing technologies

AbstractIn this study, a detailed analysis of hybrid weld manufacturing technologies that can significantly contribute to the joining of materials has been carried out. Past, present and future projection, advantages, dis advantages, technological barriers and drawbacks of the processes are given. Detailed explanations of the recent developments of hybrid weld manufacturing technologies and main components are given. Potential industrial applications are assessed and evaluated using economic and technological results. The developments in hybrid welding manufacturing technologies generally improved metallurgical and mechanical properties of weld joints. Hybrid processes usually combine the benefits of each individual process. Due to low heat input, hybrid welds create fine grain structures, minimize base material dilution and achieve high toughness and mechanical properties. These processes are especially appropriate for high performance alloys and dissimilar metal joining. The results of this study conclude that reasonable costs and improved properties of the processed materials will lead to massive use of hybrid welding manufacturing technologies.

나노스케일 3 차원 프린팅 시스템을 위한 정렬 알고리즘

Hybrid manufacturing technology has been advanced to overcome limitations due to traditional fabrication methods. To fabricate a micro/nano-scale structure, various manufacturing technologies such as lithography and etching were attempted. Since these manufacturing processes are limited by their materials, temperature and features, it is necessary to develop a new three-dimensional (3D) printing method. A novel nano-scale 3D printing system was developed consisting of the Nano-Particle Deposition System (NPDS) and the Focused Ion Beam (FIB) to overcome these limitations. By repeating deposition and machining processes, it was possible to fabricate micro/nano-scale 3D structures with various metals and ceramics. Since each process works in different chambers, a transfer process is required. In this research, nanoscale 3D printing system was briefly explained and an alignment algorithm for nano-scale 3D printing system was developed. Implementing the algorithm leads to an accepted error margin of 0.5% by compensating error in rotational, horizontal, and vertical axes.

Planar Structure Optimization of Extraordinary Magnetoresistance in Semiconductor–Metal Hybrids

The performance of extraordinary magnetoresistance (EMR) depends on the material parameters, hybrid structure design, contacts configuration, and manufacturing technology. In this paper, we pay close attention to the hybrid structure of the EMR device. A semiconductor–metal hybrid model based on the finite element method (FEM) is constructed to study the EMR effect, and the results show good agreement with the experimental data. The analysis of the van der Pauw plate structure indicates that the relationship between the two voltage probe contacts and the different EMR structures is the key factor to the design optimization. Accordingly, we find that the elliptic inclusion configurations improve the performance of the van der Pauw structure of EMR devices within a wide range of applied magnetic field (0–5 T). The bar-type and multibranched inclusion structures are subsequently optimized based on this principle. The new structures show excellent performance; more specifically, the modified multibranched inclusion structure displays a 2-fold increase in the magnetoresistance at 0.1 T and more than 2-order-of-magnitude increase at 5 T when compared with the original structure.

A review of hybrid manufacturing processes – state of the art and future perspectives

Today, hybrid manufacturing technology has drawn significant interests from both academia and industry due to the capability to make products in a more efficient and productive way. Although there is no specific consensus on the definition of the term ‘hybrid processes’, researchers have explored a number of approaches to combine different manufacturing processes with the similar objectives of improving surface integrity, increasing material removal rate, reducing tool wear, reducing production time and extending application areas. Thus, hybrid processes open up new opportunities and applications for manufacturing various components which are not able to be produced economically by processes on their own. This review paper starts with the classification of current manufacturing processes based on processes being defined as additive, subtractive, transformative, joining and dividing. Definitions of hybrid processes from other researchers in the literature are then introduced. The major part of this paper reviews existing hybrid processes reported over the past two decades. Finally, this paper attempts to propose possible definitions of hybrid processes along with the authors’ classification, followed by discussion of their developments, limitations and future research needs.

Risk assessment of hybrid manufacturing technologies for ramp-up projects

Hybrid manufacturing technologies often provide a high potential for innovation and are not widely used in industries. Therefore the ramp-up of hybrid manufacturing technologies is a special challenge. The aim of this article is to show how hybrid manufacturing technologies can be found and evaluated. In the first part a method to identify hybrid manufacturing technology concepts for the supplementation of conventional technologies is introduced. The second part presents an evaluation of these new technologies in the context of production ramp-up projects. Thus, the optimal hybrid manufacturing technology can be chosen during the production process planning of new products.

Modelling the Cutting Process and Cutting Performance in Abrasive Water jet Machining Using Genetic-Fuzzy Approach

Unconventional machining processes are used only when no other traditional machining process can meet the necessary requirements efficiently and economically. Abrasive Waterjet Machining (AWJM) is one of the most recently developed mechanical type unconventional hybrid manufacturing technologies. It is superior to many other cutting techniques in processing various materials, particularly in processing difficult to cut materials. This technology is being increase used in various industries. Therefore, optimum choice of the process parameters is essential for the economic, efficient, and effective utilization of these processes. Process parameters of AWJM are generally selected either based on the experience, and expertise of the operator or from the propriety machining handbooks. In most of the cases, selected parameters are conservative and far from the optimum. This hinders optimum utilization of the process capabilities. Selecting optimum values of process parameters without optimization requires elaborate experimentation which is costly, time consuming, and tedious. Process parameters optimization of AWJM essential for exploiting their potentials and capabilities to the fullest extent economically. This paper presents a Fuzzy Logic (FL) - based modeling of AWJM process and optimization of its rule base, data base and consequent part utilizing a Genetic Algorithm (GA). A binary coded GA has been used for the said purpose. While modeling with FL, the output parameters, namely Material Removal Rate (MRR) and Surface Finish (Ra) have been predicted for different combinations of process parameters, such as waterjet pressure at the nozzle exit diameter of abrasive-water jet nozzle traverse or feed rate of the nozzle mass flow rate of water and mass flow rate of abrasives between nozzle and the work piece.

Ramp-up of hybrid manufacturing technologies

Hybrid manufacturing technologies provide a high potential in enhancing manufacturing process capabilities in terms of new product properties and sustainable production. Combining two or more technologies in one process or machine result in a larger range of options for the creation and optimization of technology chains. Sustainability is an important objective when using hybrid processes but also economic targets can be achieved. The aim of this paper is to present a method for detecting and evaluating hybrid manufacturing technologies and implementing them at the right moment into an existing production environment. A decision has to be made, whether a certain hybrid technology is suitable or not. To make this decision a risk-and-potential analysis of manufacturing technologies was developed. In the first part this article will provide an introduction to hybrid manufacturing processes. Further a design approach for hybrid technologies is shown. The second part concentrates on the possible implementation of manufacturing technologies during the ramp-up phase into the production environment.

Developing a manufacturing technology for the components made of a multiphase perfect material

A component made up of a perfect combination of different materials (most often including homogeneous materials and three different types of heterogeneous materials, i.e., composite materials, functionally graded materials, and heterogeneous materials with a periodic microstructure) in its different portions for a specific application is considered to be a component made of a multiphase perfect material. To design and represent such components, a corresponding computer-aided design method and a CAD modeling method have been developed. Although, there is no existing manufacturing method and facility for such components. Their fabrication entails four steps described in this paper: analysis of the requirements of their manufacture; review of the currently available layered manufacturing, micro-fabrications, and hybrid manufacturing technologies; presentation of a new hybrid layered manufacturing technology (including its manufacturing process and the principle scheme of its corresponding manufacturing facilities); and implementation of the manufacturing simulation by means of virtual manufacturing technology.