Designing and Redesigning Products, Processes, and Systems for a Helical Economy

The Circular Economy (CE) concept has promised to unlock trillions of dollars in business value while driving a significant reduction in the world’s resource consumption and anthropogenic emissions. However, CE mainly lives in ambiguity in the manufacturing domain because CE does not address the changes needed across all of the fundamental elements of manufacturing: products, processes, and systems. Conceptually, CE is grounded in the concept of closed-loop material flows that fit within ecological limits. This grounding translates into a steady state economy, a result that is not an option for the significant portion of the world living in poverty. Therefore, this paper proposes the Helical Economy (HE) concept as a novel extension to CE—one that allows for continued innovation and economic growth by leveraging an Internet of Things (IoT) infrastructure and by reimagining products, processes, and systems. This paper intends to be the conceptual overview and a framework for implementing Helical Economy in the manufacturing domain

Metrics-based Sustainability Evaluation of Cryogenic Machining

Cryogenic machining is considered as the most sustainable alternative to conventional flood-cooled, near-dry and dry machining approaches in machining processes. This paper presents the application of a sustainability evaluation methodology for manufacturing processes, focusing on cryogenic machining processes. The methodology used here involves a metrics-based Process Sustainability Index (ProcSI) evaluation. To address the proper process conditions for cryogenic machining, different machining parameters, namely the cutting speed and the coolant flow rate, are used in the experiments as the controllable variables. The ProcSI assessment helps to decide on the best cutting conditions from the sustainable manufacturing viewpoint. During the evaluation procedure, the process behavior under different process conditions is considered and discussed in the analysis to understand the process mechanism and its controllability for achieving improved sustainability

Strategies for Value Creation Through Sustainable Manufacturing

Making the business case and establishing strategic directions for sustainable manufacturing requires a collaborative effort. Strategic capabilities that can help create sustainable value for all stakeholders must be identified. Technologies and methodologies to provide these capabilities for implementation must then be developed, through public-private partnerships. This paper presents major business imperatives and strategic capabilities necessary to enable value creation through sustainable manufacturing identified based on extensive engagement with business leaders and industry professionals as well as academic experts and government agency representatives. The paper also presents a future vision for sustainable products, processes and systems that can be derived from such capabilities

Modeling and Simulation of Machining-induced Surface Integrity Characteristicsof NiTi Alloy

AbstractNiTi shape memory alloys have gained increased interest in various industries, including biomedical and aerospace applications due to their unique properties such as shape memory effect and superelasticity. Martensitic phase transformation in NiTi significantly affects the surface integrity characteristics. This phase transformation needs to be better understood to control and enhance the shape memory and microstructural properties of NiTi shape memory alloys. This study presents results of combined experimentation and simulation of cutting-induced phase transformation in orthogonal machining of NiTi shape memory alloys. A phenomenological modeling approach was utilized to model machining-induced phase transformation. NiTi shape memory alloys alloy were in austenite phases at room temperature. The transformation during dry machining process from austenite to martensite phases, and the resulting volume fraction was successfully simulated using DEFORM 2-D software by implementing a user-defined subroutine. The developed model is capable of capturing the trend of variationsinvolume fracture and the depth of transformed layer as a function of cutting speed

A Total Life Cycle Approach for Developing Predictive Design Methodologies to Optimize Product Performance

Sustainable products must be designed by considering how design decisions impact their total life cycle (TLC) sustainability content. Even more so important when designing products to incorporate the technological elements of sustainable manufacturing, the 6Rs (Reduce, Reuse, Recycle, Recover, Redesign and Remanufacture), to achieve Circular Economy (CE). This paper presents the preliminary work of an ongoing research project on developing a novel framework incorporating predictive models with TLC considerations. This unique approach develops and integrates models with associated risks, and optimizes for maximizing the sustainability benefits due to design decisions. Such predictive capability is extremely useful for process planning, where careful planning and optimization of process conditions would allow inducing favorable product performance and improved sustainability

A thermal analysis framework for cryogenic machining and its contribution to product and process sustainability

Part of: Seliger, Günther (Ed.): Innovative solutions : proceedings / 11th Global Conference on Sustainable Manufacturing, Berlin, Germany, 23rd - 25th September, 2013. - Berlin: Universitätsverlag der TU Berlin, 2013. - ISBN 978-3-7983-2609-5 (online). - http://nbn-resolving.de/urn:nbn:de:kobv:83-opus4-40276. - pp. 262-267.Cryogenic processing methods are environmentally-clean, toxic-free, and safe sustainable manufacturing processes, which also provide improved surface integrity, superior functional performance and greater product life in manufacturing processes. This paper presents a summary of findings from a preliminary study of the cryogenic cooling effects in a machining process. Various heat transfer scenarios need to be built into the model to consider the boiling phenomena. Cryogenic turning process includes a large radial thermal gradient in a thin layer of machined surface and changes the dynamic recrystallization process. A high speed, wide range temperature measurement system was developed, and preliminary experiments are carried out, investigating the contributing factors and the proper boundary conditions for modeling of cryogenic machining processes. The transition from slow cooling to a rapid cooling is observed

Towards Developing Sustainable Reconfigurable Manufacturing Systems

This paper aims to examine the sustainable manufacturing performance of Reconfigurable Manufacturing Systems (RMSs) using existing sustainable manufacturing metrics. RMS has six key characteristics including modularity, integrability, customization, scalability, convertibility, and diagnosability. In this paper, ‘convertibility’ is quantified by considering configuration convertibility, machine convertibility, and material handling device convertibility from the RMS perspective. In addition, the performance of RMSs with different convertibility levels is also evaluated by using sustainable manufacturing metrics. A numerical example is used to demonstrate the computational approach. Results of the analysis are used to show how sustainable manufacturing performance of RMS changes as system convertibility varies. The findings show that RMS sustainable manufacturing performance can be improved by selecting a suitable level of convertibility

Innovation in sustainable manufacturing education

Part of: Seliger, Günther (Ed.): Innovative solutions : proceedings / 11th Global Conference on Sustainable Manufacturing, Berlin, Germany, 23rd - 25th September, 2013. - Berlin: Universitätsverlag der TU Berlin, 2013. - ISBN 978-3-7983-2609-5 (online). - http://nbn-resolving.de/urn:nbn:de:kobv:83-opus4-40276. - pp. 9-16.Sustainable value creation entails generating value for all stakeholders from economic, environmental and social perspectives. In a manufacturing context, creating sustainable value requires product, process and systems level innovations to enable near-perpetual closed-loop material flow across multiple life-cycles; it also requires understanding the complex interactions of the socio-technical systems with the natural environment for emergent synthesis so sustainable value creation can occur harmoniously and continuously. However, current educational curricula with traditional disciplines is fragmented and do not represent the multidisciplinarity or the integration needs; it is now necessary to work at the interface of the various disciplines to address the complex issues that are brought about through sustainability. Thus, to create sustainable value through sustainable manufacturing will require transformational and innovative reforms in education with an overall paradigm shift to provide the future generation of engineers, scientists and managers the necessary technical knowledge, skills and capabilities. This paper presents recent trends in developing such innovative educational programs in sustainable manufacturing. Also, the technological challenges posed by the need for implementing viable innovative sustainable manufacturing educational programs inevitably require fundamental studies on total life-cycle products, closed-loop manufacturing processes and integrated production systems extending beyond to the entire supply chain operations. This paper is aimed at tackling these significant challenges by essentially developing sustainable value propositions for all forms of educational programs (formal degrees and certificate level programs, professional/continuing education programs, short courses and web-based interactive learning programs, etc.) to incorporate the new knowledge needed to promote value-added sustainable manufacturing at product, process and system levels

Sustainable value creation through innovative product design

Part of: Seliger, Günther (Ed.): Innovative solutions : proceedings / 11th Global Conference on Sustainable Manufacturing, Berlin, Germany, 23rd - 25th September, 2013. - Berlin: Universitätsverlag der TU Berlin, 2013. - ISBN 978-3-7983-2609-5 (online). - http://nbn-resolving.de/urn:nbn:de:kobv:83-opus4-40276. - pp. 60-65.In the field of product development, many organizations struggle to create a value proposition that can overcome the headwinds of technology change, regulatory requirements, and intense competition, in an effort to satisfy the long-term goals of sustainability. Today, organizations are realizing that they have lost portfolio value due to poor reliability, early product retirement, and abandoned design platforms. Beyond Lean and Green Manufacturing, shareholder value can be enhanced and optimized by taking on a broader perspective, and integrating sustainability innovation elements into product designs. This paper presents a framework for achieving the goal of mutual value creation, and identifies the drivers of product design that are used to ultimately create what is termed - The Sustainable Products Value Proposition. Focus is placed on a balanced approach towards the integration of total cost of ownership, social and environmental improvements, and an expanded definition of product life drivers

Analysis of Surface Integrity in Machining of AISI 304 Stainless Steel Under Various Cooling and Cutting Conditions

Recent studies have shown that machining under specific cooling and cutting conditions can be used to induce a nanocrystalline surface layer in the workspiece. This layer has beneficial properties, such as improved fatigue strength, wear resistance and tribological behavior. In machining, a promising approach for achieving grain refinement in the surface layer is the application of cryogenic cooling. The aim is to use the last step of the machining operation to induce the desired surface quality to save time-consuming and expensive post machining surface treatments. The material used in this study was AISI 304 stainless steel. This austenitic steel suffers from low yield strength that limits its technological applications. In this paper, liquid nitrogen (LN2) as cryogenic coolant, as well as minimum quantity lubrication (MQL), was applied and investigated. As a reference, conventional flood cooling was examined. Besides the cooling conditions, the feed rate was varied in four steps. A large rounded cutting edge radius and finishing cutting parameters were chosen to increase the mechanical load on the machined surface. The surface integrity was evaluated at both, the microstructural and the topographical levels. After turning experiments, a detailed analysis of the microstructure was carried out including the imaging of the surface layer and hardness measurements at varying depths within the machined layer. Along with microstructural investigations, different topological aspects, e.g., the surface roughness, were analyzed. It was shown that the resulting microstructure strongly depends on the cooling condition. This study also shows that it was possible to increase the micro hardness in the top surface layer significantly