Sustainability Assessment of Products manufactured by the Laser Powder Bed Fusion (LPBF) Process

Assessing the sustainability of a product is dependent on considering individual product life cycle data. Based on the information on material, energy and information flows, evaluation tools such as the life cycle assessment (LCA) or the calculation of the cumulative energy consumption can be used. Especially the methodology of LCA according to ISO 14040/44 allows a selection of alternative analysis and measurement cycles as well as a combination of impact assessment indicators that have a direct and significant influence on sustainability. The comparison of various manufacturing processes allows the identification of relations between the applied evaluation tools and the product- as well as process-specific parameters during the production phase, and throughout the entire product life cycle. Within the various case studies considered, a distinction can be made both between the definition and the indicators of sustainability and between the ecological, economic or social dimensions within the motivation formulated. This paper describes the results of the literature review on the sustainability assessment of additive manufacturing processes in general as well as the Laser Powder Bed Fusion process as an example. A research map shows which phases of the product life cycle of an additive manufactured component are considered and which methods can be used to assess their sustainability. The result is a summary of the state of the art regarding the methods of sustainability assessment of additive manufacturing processes. In addition, an outlook can be determined on how the different phases of the product life cycle can be evaluated with tools that currently receive less attention

An approach for choosing the cost effective design for a product-service system while maintaining its desired reliability

With the spread of product-service systems as business models the life cycle costs are of increasing importance as a measurement of product cost. A key factor that drives these costs is the desired reliability of the products used to provide the service. Since the customer usually expects as uninterrupted service availability, it is imperative to achieve the the required reliability. Therefore a large variety of methods has been developed to maximize the reliability of a product. But these approaches focus on the maximization of the reliability and disregard the resulting product costs. This can lead to designs that over perform concerning their reliability requirements but also exceed their target costs. Which will result in the product-service system not being competitive in the marketplace or lowering the company's profit. This paper shows an approach on how to use markov chains to enable a quick comparison of life cycle costs from different product-service system designs With this it will be possible to make better informed decisions about the costs of a system while still meeting the reliability targets. © 2019 Design Society. All rights reserved

Design of hybrid components joining zone through sensitivity analysis

Multi-material structures are a trending topic for the industry. With a high application potential, such as lightweight or extended life cycle, different manufacturing technologies are further developed for this intent. One of these technologies is Tailored Forming, a process-chain capable of joining different metals and creating massive hybrid components. In parallel to this development, new challenges rise for design, which has the responsibility of finding an optimal use of this technology and produce higher-performance products. However, this task cannot be solved by conventional engineering approach, since strong manufacturing constraints are involved and a lack of understanding about the joining zone formed between the materials still exists. To fill this gap, the objective of this study is to analyse the influence of the joining zone design over the structure behaviour and establish a suitable design method. For that, a computer-aided environment was constructed and a parametric sensitivity analysis was executed, taking a hybrid shaft as example. At the end, the simulation's results allowed a multi-objective optimisation and were able to generate first design guidelines. © 2019 Design Society. All rights reserved

Development of a Domain-Specific Ontology to Support Research Data Management for the Tailored Forming Technology

The global trend towards the comprehensive digitisation of technologies in product manufacturing is leading to radical changes in engineering processes and requires a new extended understanding of data handling. The amounts of data to be considered are becoming larger and more complex. Data can originate from process simulations, machines used or subsequent analyses, which together with the resulting components serve as a complete and reproducible description of the process. Within the Collaborative Research Centre "Process Chain for Manufacturing of Hybrid High Performance Components by Tailored Forming", interdisciplinary work is being carried out on the development of process chains for the production of hybrid components. The management of the generated data and descriptive metadata, the support of the process steps and preliminary and subsequent data analysis are fundamental challenges. The objective is a continuous, standardised data management according to the FAIR Data Principles so that process-specific data and parameters can be transferred together with the components or samples to subsequent processes, individual process designs can take place and processes of machine learning can be accelerated. A central element is the collaborative development of a domain-specific ontology for a semantic description of data and processes of the entire process chain

Product data management in the context of Industry 4.0

Industry 4.0, known as the fourth industrial revolution, generates great potential for self-organized, networked products. Industry 4.0 products have the ability to detect the environmental conditions and are enabled to communicate with each other. They collect lifecycle data, verify information and transfer them back to the product development. The information are used to create a new product generation. Product Data Management Systems (PDM) are used conventionally during the product development phase. In this paper the requirements of Industry 4.0 products are analyzed for PDM Systems. An analysis of six PDM Systems with the greatest market share are provided. At the example of a torch it is demonstrated how a PDM Systems is used to develop and manage the data of an Industry 4.0 product

Implementation of maintenance strategies in the life cycle costing of product-service systems

Estimating the costs of products during development to design a cost efficent product is a well established process. But in the case of Product-Service Systems estimating the costs of the individual product is not sufficent. Instead it is necessary to calculate the cost incured over the entire life cycle of the product. Because with Product-Service Systems the majority of costs is not incurred during manufacturing of the product but instead during the operation. One of the major cost components accruing during the operation of the product are the maintennace costs. Therefore, current life cycle costing models show the impoact of component design on the maintennace cost of the Product-Service System. But they do not show how different maintennace strategies that can have an impact on the overall life cycle costs of the Product-Service System. Thus, this paper shows a method for the implementation of different maintennace strategies into life cycle costing and applies it in an industrial use case

Identification of dynamic loads on structural component with artificial neural networks

Enhancing structural components by implementing sensors offers great potential regarding condition monitoring for lifetime analysis, predictive maintenance and automatic adaptation to environmental conditions. This article describes an approach to determining the operational forces applied to the front suspension arm of a car using strain gauges. Since suspension arms are components with free-form surfaces, an analytical calculation of applied forces by means of measured strains is not feasible. Hence, artificial neural networks are applied to approximate the functional relationship. The results reveal how artificial neural networks can be applied to identify load conditions on structural components and, therefore, deliver essential data for condition monitoring

STAGES OF BIOFILMS FORMATION BY THE LEADING PATHOGENS IN CHILDREN WITH PYELONEPHRITIS ON CONGENITAL HYDRONEPHROSIS BACKGROUND DEPENDING ON CHILD’S AGE

The aim: to study the stages of primary and secondary biofilms formation by the leading pathogens in children with pyelonephritis on congenital hydronephrosis background depending on child’s age. Materials and methods. Venflons, catheters, urine were used as material for microbiological study. Identification of microorganisms was provided with MICRO-LA-TESTÒID kits. Isolates were tested for ability to form biofilms in Petri dishes with d=40 mm. The morphological structure of the biofilms was studied by scanning electron microscopy. Results: The study of structural and functional features of biofilms formation by leading pathogens of in children with pyelonephritis on congenital hydronephrosis background depending on child’s age revealed a number of features and patterns. In addition to the classical stages of biofilms formation as 3D structure there was found a dissemination of planktonic cells with the release of bacteria or loss of single fragments that spread throughout the body and attach to the substrate with the formation of a new or secondary biofilm. In children under 3 years it was shown that the cocci attachment to the substrate appeared faster than in gram-negative rods and had appearance of separate structures. The longest stage of primary biofilms formation in young children was the co-aggregation. Detecting an ability to colonize with the formation of a secondary biofilm in isolates established that the longest stage was re-adsorption and the shortest was re-aggregation, which lasted 2 hours in all detected pathogens. In middle-aged children, the duration of adhesion stage was reduced by 1-2 hours compared with it in young children. Conclusions. Scientific data about the stages of biofilms formation by microorganisms, causative agents of pyelonephritis in children was updated. Adhesion stage of isolates from elder children with pyelonephritis on background of congenital hydronephrosis underwent faster in the formation of secondary biofilms than in primary, and it formed the possibility for chronic process and the development of recurrences. The duration of each stage in biofilms formation by causative agents of pyelonephritis in children with congenital hydronephrosis depended on the age of the child and the properties of microorganism

Prediction of continuous cooling diagrams for the precision forged tempering steel 50CrMo4 by means of artificial neural networks

Quenching and tempering of precision forged components using their forging heat leads to reduced process energy and shortens the usual process chains. To design such a process, neither the isothermal transformation diagrams (TTT) nor the continuous cooling transformation (CCT) diagrams from literature can be used to predict microstructural transformations during quenching since the latter diagrams are significantly influenced by previous deformations and process-related high austenitising temperatures. For this reason, deformation CCT diagrams for several tempering steels from previous works have been investigated taking into consideration the process conditions of precision forging. Within the scope of the present work, these diagrams are used as input data for predicting microstructural transformations by means of artificial neural networks. Several artificial neural network structures have been examined using the commercial software MATLAB. Predictors have been established with satisfactory capabilities for predicting CCT diagrams for different degrees of deformation within the analyzed range of data.DFG/CRC/48

Concept and Implementation of a Student Design Project for the Development of Sustainable Products

Technology is a major driver for leveraging the potential of multidimensional sustainable development, regardless of the sector examined. Therefore, engineers have an important contribution in developing innovative technical solutions to ensure more sustainable alternatives to conventional processes or products. In order to support this comprehension from an early age on, it is the task of lecturers at universities by developing students access to sustainable engineering activities with new teaching programs. Regarding conventional product development, the question arises how sustainable products can be developed, which concepts for design and which methods for validation and quantification can be used. These and further questions are the basis of the project-based learning (PBL) approach introduced in this paper as part of a new module "Development of Sustainable Products" at the Faculty of Mechanical Engineering at the Leibniz University Hannover. In this paper, the need for new courses in the ecological sustainability context and the requirements for student project work are presented. The concept of the project and the overall objective, that the students are required to assess the ecological environmental impact of electric toothbrushes over the entire product life cycle based on a life cycle assessment (LCA) is introduced. After successfully participating in this project, students are able to conduct ecological sustainability analyses and understand the complexity within the development of sustainable products