Recent Trends in Sustainable Manufacturing (Trend Terkini dalam Pembuatan Lestari) Abdullah Almutairi, Mohammad AlMutairi, Bader AlOqab, Mohammad Alghadhori & Ahmad Alotaibi Mechanical Engineering Programme, Centre for Engineering Materials and Smart

Manufacturing (MERCU), Centre for Integrated Design of Advanced Mechanical System (PRISMA), Faculty of Engineering & Built Environment, Universiti Kebangsaan Malaysia, Malaysia ABSTRACT There has been an increasing concern about the environment, scarcity of resources and more consumer pressure for eco-friendly products pressurise manufacturers towards sustainable practices. The main objective of this study was to determine the recent trends in sustainable manufacturing. This study begins by introducing key concepts including Triple Bottom Line which involves Balancing economic sustainability, developing sustainable environment and social responsibility. Secondly, it introduces the Life Cycle Assessment (LCA) which deals with the Life cycle assessment of products. Third, it looks at Circular Economy which involves reducing waste and enhancing resource use through recycling and re-use. The work also looks at the recent technological advances that include Industry 4.0 & Smart Manufacturing which revolves around the application of digital technologies and data analytics to improve resource efficiency and avoid waste. The work also looks at Additive Manufacturing (3D Printing), Sustainable Materials & Nanotechnology and Supply chain transparency & sustainability. The review concludes with the statement that Sustainable manufacturing is transforming from a supplemental approach to the fundamental way of operating. Technology, changing tastes and working in unison towards a shared goal is essential for this future where manufacturing will grow with the planet's health. Introduction Key words: Triple Bottom Line: Life Cycle Assessment, Circular Economy, Industry 4.0 & Smart Manufacturing, Additive Manufacturing (3D Printing), Sustainable Materials & Nanotechnology. The environmental and social pressure is responsible for the paradigm shift of global manufacturing. These changes have given a rise to a design of sustainable manufacturing that lays focus on minimizing environmental effects thereby enhancing efficient use of resources as well as enhancing social prosperity throughout a product lifespan. The economic forces behind this sustained growth and increased efficiency are not the only determining factors environmental and societal pressures have been edging global manufacturing practices to adapt to a more sustainable landscape. In the face of climate changes that are inadvertently accelerated by industrialization, coupled with a resource depletion and social inequality challenges manufacturing must innovate its thought patterns. A shift in paradigm towards eco-design has therefore become a necessity as manufacturing organizations begin to adopt environmental friendly designs that not only reduce resource wastage but also the life times of these products over their entire existence. This is a literature review that seeks to explore the recent developments in sustainable manufacturing, covering the changing trends that are leading in redefining practices of industry operations. Environmental friendly manufacturing refers to the use of green technologies and clean sources of energy as an essential aspect sustainable manufacturing. Manufacturers are presented with sustainable energy sources such as solar, wind, and hydropower technologies that allow for great potential to result in subsequent minimizing of GHG emissions. The manufacturing of processes is becoming more efficient with the adoption of new Industry 4.0 technologies that introduce IoT 1 sensors and intelligent energy-managing systems. These technological integrations are not only helpful for environment sustainability but accompany a saving benefit during all the courses of manufacture around economy. One of the key areas that have become very debatable in recent years is a more and more attention to eco-design, as well as sustainable materials. They are rigorously looking for substitutes to traditional materials, preferring biomaterials or maxi-life cycle recycled or upcycled materials with a lower environmental impact. The Eco-design principles are now encompassed into the implementation process or in other words, considerations for responsible use of environmental resources get integrated built from the beginning. This strategy not only matches the demands of environmentally-friendly products by customers but also has to take into consideration regulatory pressure that promotes guileless sourcing and production done. As sustainable manufacturing extends beyond the confines of single production processes, it is instead taking a complete look at the supply chain. Manufacturers are also beginning to appreciate the need to embark upon sustaining principles of production and administration. The digital wave is a key player in sustained production. Tools of Industry 4.0 like data study, AI, and the Internet of Things give companies brand new understanding. Maintenance that predicts issues, monitoring in real-time, and clever transport help use resources well, cut down waste, and boost performance. Applying decisions based on data lets companies spot chances to improve and put eco-friendly steps in place across operations. All around the world, tighter environmental laws are being enforced. This forces factories to meet tough eco-friendly rules. They don't just have to follow the law but also have to keep their image good. So, factories are putting money into clear systems. These show how they're helping the environment. They also show they're honest and responsible to their customers and the law. Working together has become key for environmentally friendly manufacturing. Companies are teaming up more and more with groups outside of the government, governments themselves, and other people in the industry. They're doing this to take on sustainability issues that everyone shares. The purpose of these team efforts is to create rules, share successful methods, and reach common goals for sustainability. These team efforts encourage new ideas. Plus they also make it easier for the industry to adopt sustainable practices on a large scale. Not just the environment, but businesses also see it's important to care about people's welfare. Employing people legally, giving everyone a chance, and paying rightly are becoming parts of smart manufacture. Folks are more aware of how their buying matters to society and firms are reacting by being good across their actions. Minding both green and social needs shows an all-round way of lasting in production. Environmental Imperatives: importance to succeed in sustainable manufacturing also reveals as progressive motivation that drives environmental challenges, providing the priority process of creation. Push to climate change, pollution, and their ecological crypto is forcing manufacturers into such practices that enable them not only to mitigate or reduce on the negative impact but also quicken sustainability. The idea of a circular economy has been popularly discussed as an approach which even in principle deviates from the model of linear production but advocates for economies which are effective and profit value retention, reduce or eliminate wastes and consequently extends longevity while enjoying continued product quality. The moves towards the circular economy are redefining the production mechanism to return and convert materials into products resubmitted for use rather than directly disposing them producing minimal environmental impact. Environmental Impact Personnel Health Operational Safety Sustainable Manufacturing Processes Manufacturing Cost The Energy Consumption Waste Management Figl: The elements of sustainable manufacturing processes Sustainable manufacturing represents a vital reaction to rising global awareness of environmental issues, resource depletion and social consequences for industrial activity (Grzegorz, Królczyk & Małgorzata, 2020). Sustainable manufacturing is an attempt to achieve the harmonization of economic, environmental and social aspects leading up to a balanced sustainable industrial ecosystem. Environmental stewardship, economic viability and social responsibility are diverse but interrelated values that must be linked to sustainable manufacturing. In an ecological point of view, old manufacturing methods have been known to exhaust resources, pollute the environment and 2 result in large amounts of carbon emissions (Gupta & Konstantinos, 2021). Thus, sustainable manufacturing is aimed at addressing these negative effects through cleaner production alternatives, promoting waste reduction and supporting eco-friendly technologies (Grzegorz, Królczyk &Wzorek, 2020). Sustainable manufacturing reduces the environmental footprint and thus helps in protecting ecosystems, biodiversity, and also enhances overall health of our planet. From an economic standpoint, sustainable manufacturing has become one of the strategic approaches to guarantee long term business success (Lin L. & MengChu, 2023). Companies that emulate the sustainability culture often achieve improved efficiencies, cost savings through optimization of resources and better risk management. Additionally, increasing environmental awareness among consumers translates into a competitive advantage in the sustainable manufacturing through promoting demand for eco-friendly products and brand loyalty. Another important aspect of sustainable manufacturing is social responsibility. Apart from environmental concerns, sustainability goes beyond the treatment of workers and includes issues on local communities as well society in general (Jayakrishna et al., 2023). This includes fair labor practices, inclusivity and the promotion of diversity workforce. Companies that practice eco-conscious manufacturing place the interests of their employees above all else resulting in better social development. Economic 5% TBL 21% Environmental 25% Environmental & Social 1% Environmental & Economic 48% Fig 2: The impact to various industries as a result of Recent Trends in Sustainable Manufacturing Growing global awareness of environmental issues and the need for sustainable practices in manufacturing. Environmental issues have created a mind shift of manufacturing industry and therefore the need for comprehensive integration sustainable practices is essential. Surging climate change, resource depletion and ecological destruction have increased consumer awareness of policymakers and business owners (Pardeep & Anamika, 2023). The awareness to that is based on the understanding of old manufacturing approaches, which cannot be characterized as energy efficient and are major threats for Earth's health. The necessity of eco-friendly practices in manufacturing stems from the fact that such industrial activities contribute substantially to environmental degradation. Such consequences as pollution, deforestation and the depletion of nonrenewable natural resources require immediate action. States and multinational agencies are reacting to these challenges by developing tight environmental laws and criteria that require industries to move in the environment-friendly solutions direction while minimizing their ecological imprint (Pardeep & Anamika, 2023). In addition, consumers are becoming more inclined towards environmentally benevolent options that demand honesty and responsibility from manufacturers. This change in consumer behavior has pushed companies to reconsider their production strategies focusing on waste minimization and sustainable supply chain management, energy efficiency as well as ecological sourcing. Companies have become aware of the fact that adopting sustainability does not only respond to ethical values but it also proves a competitive advantage when environmental responsibility is viewed as one of consumer loyalty criteria. On a global level, this awareness has also led to creative collaborations among industry leaders, environmentalists and policy makers engaged in finding innovative solutions. Considering that green manufacturing is necessary to preserve the environment, it also becomes stimulating for economic growth. Principles of sustainability as part of manufacturing are considered a fundamental approach towards strengthening resilience, long-term viability and promoting balance between human development goals and environmental preservation (Sunil, Dixit & Ashish, 2021). The increase in the awareness of sustainability issues on a global scale has created impetus for sustainable practices in manufacturing which is represented through conscious and responsible industrial operations. an 3 Key Concepts and Frameworks of Sustainable Manufacturing Triple Bottom Line Approach This central principle of sustainable manufacturing illustrates how economic, social and environmentally aspects are interrelated. Historically, business success could be measured only by a bottom line result. The TBL builds on this view by claiming that profitable enterprises should be concerned with people (social), the environment (planet), and profits(economic). This all-inclusive approach understands that sustainability is realized through the delicate balance of these three dimensions. Sustainable manufacturing requires a careful balance between the economic viability, social responsibility and environmental stewardship. Economic success guarantees the survival of an enterprise but not at any social costs or on the detriment of nature (Ding & Runeson, 2020). Firms adopting the TBL approach are aware that sustainable profitability is underpinned on ethical and green practices. The integration of social and environmental concerns into decision- making processes can help manufacturers improve its reputation, encourage employee satisfaction, as well as contribute to broader goals for sustainability (Gary, 2018). Life Cycle Assessment (LCA) Life Cycle Assessment (LCA) is a comprehensive study on the environmental impact of products during their entire life cycle, including raw material extraction, manufacturing process, distribution phase and disposal. The advantage of LCA is that it gives a complete picture about the environmental foot print linked with a product which in turn allows manufacturers to detect opportunities for improvement and make relevant decisions (Walter & Grahl, 2014). LCA allows quantifying the environmental impacts of manufacturing leading to strategies and processes aimed at minimizing resource consumption, energy use, gas emissions and so on favouring more sustainable practices. Goal and Scope Definition Inventory Analysis Impact Assessment Interpretation Fig 3: Life cycle assessment Cases of LCA in Sustainable Manufacturing Studies It has been widely used in numerous sustainable manufacturing studies for assessment and improvement of the environmental performance. For example, LCA has been used to assess the ecological impact of diverse packaging materials that manufacturers can select alternative ones with a low environmental footprint. In the automotive industry, LCA has led to designs of cars that emit little carbon footprints and increased energy performance (Walter & Grahl, 2014). These cases demonstrate the usefulness of LCA in supporting decision-making for organizations that wish their manufacturing practices to conform with sustainability objectives Circular Economy The Circular Economy is an economic model that focuses on the reduction of waste and maximum usage of resources by encouraging ongoing use, recycling, repurposing products (Kyle & Eric, 2021). Under the framework of manufacturing, circular economy aims at shifting from 'take-make dispose' to more sustainable closed loop system. This includes developing long- lasting products, reusing and recycling materials, or nurturing a regenerative system of production Re-mine Recover Recycle Repurpose Refuse Circular economy model Remanufacture Reduce Resell/Reuse Repair Refurbish Fig 4. The circular economy model. Circular Economy Practices in Manufacturing Both the private and public sectors are implementing circular economy practices in their value chains (Kyle & Eric, 2021). For example, many fashion brands recycle materials in clothing lines to prolong textile lifespan. The take-back programs undertaken by electronics manufacturers allow the recovery and reuse of valuable components from discarded products Davide A, Claudia G, Stefano P, Marco. (2022).. These examples show that adopting the principles of circular economy can not only eliminate unnecessary waste, but also provide new opportunities for innovation in manufacturing. In essence, the Triple Bottom Line approach, Life Cycle Assessment and Circular Economy are key guiding frameworks of sustainable manufacturing practices. By understanding the integration of economic, social and environmental aspects as well as using LCA and circular economy principles manufacturers can make a more sustainable industrial model. Recent Technological Advances in Sustainable Manufacturing Industry 4.0 and Smart Manufacturing Industry 4.0 also referred to as the fourth industrial revolution, signals a change in manufacturing that is marked by the integration of digital technologies, automation and data exchange. This vital approach has considerably affected sustainable manufacturing through resource efficiency improvement and waste reduction. The industry 4.0 seeks smart manufacturing systems that are driven by internet of things (IoT), artificial intelligence (AI) and analytics based on big data that can improve operational efficiency while minimizing environmental impacts (Machado & Paulo, 2020). Integration of Digital Technologies, IoT, and Data Analytics in optimizing resource use and reducing waste Smart Manufacturing is considered one of the important elements of Industry 4.0 which uses digital technologies for creating adaptable production processes. The IoT devices are incorporated in order to enable manufacturers to receive real time information relating to equipment performance, energy consumption and material flows. In addition, advanced analytic systems help in predictive maintenance, optimized production scheduling as well as waste reduction. Eventually this results in more environmentally sustainable resource efficient manufacturing process Additive Manufacturing (3D Printing) Additive manufacturing, also known as 3D printing is transforming traditional manufacturing processes. In contrast to subtractive methods that create significant material waste, 3D printing constructs products layer-by-layer thereby reducing material consumption (Andreas, Julia &, Laura, 2019). Some sustainable advantages of different 3D printing technologies such as Fused Deposition Modeling (FDM) or Stereolithography (SLA) include on-demand precise production. Sustainability case studies indicate how 3D printing supports green manufacturing processes. Companies use additive manufacturing to produce complex lightweight structures, which optimize material utilization and minimize waste. For industries like aerospace and healthcare where accuracy and customization are crucial, this technology has significantly helped reduce energy requirements while decreasing the carbon emissions related to conventional modes of production. Sustainable Nanotechnology Exploring Materials: Focus on Sustainable Materials The search for sustainable materials in the world of manufacturing entails finding alternatives which have the least impact on the environment. Biodegradable polymers, recycled metals and bio- composites have risen as they provide environmentally-friendly substitutes. Sustainable Materials and Nanotechnology have a key role in enhancing green manufacturing practices that encourage resource efficiency resulting in reduced environmental impacts of industrial processes (Laxman, Ajayan & Nirmal, 2024). 5