Repair price strongly shapes consumer decisions between repair and replacement. High repair prices relative to the cost of new products often deter repair, driving premature replacement and electronic waste. This study assesses the economic viability of repair for washing machines (WMs) and vacuum cleaners (VCs) in France and Belgium using real market data and two willingness-to-pay-for-repair (WTPR) models. Case studies of six representative appliances show a consistent pattern: low-cost products fall far outside consumers’ repair thresholds, mid-range models sit in borderline zones, and only high-end units remain economically repairable. Threshold analysis shows that repair becomes viable only at higher purchase prices, generally €300-€1,000 depending on the WTPR model, repair prices, and product tier. A market-wide Monte Carlo simulation confirms these trends. Only 5% of Belgian WMs and 16% of French WMs fall within viable repair thresholds. For VCs, around 67% of VCs sold in France and Belgium are unlikely to be repaired. Scaled to 2024 sales, this equates to roughly 3.5 million appliances in France and 1.3 million in Belgium, effectively steered toward replacement. The study offers a scalable method for estimating national repair rates and highlights the need for improved WTPR models to support emerging EU repair policies.Image, application 1Application 1

Current e-waste collection and recycling practices often fail to recover valuable materials efficiently, limiting the potential of the urban mine. Under the EIT RawMaterials-co-funded Renew project, this study evaluates and compares the environmental impacts of two developed disposal solutions, aiming at addressing environmental and operational shortcomings of existing systems while exploring pathways toward more sustainable alternatives: (i) a small collection building located in a central urban area, and (ii) an automated smart bin situated near commercial services. Utilizing the ReCiPe 2016 (H) assessment method, the research found that smart bins offer a decentralized and accessible solution, potentially improving e-waste collection rates per kg. The results indicate that smart bins can substantially minimize environmental impacts, as traditional systems would need to collect nearly twice the amount of e-waste to approach the smart bin’s per-kilogram performance, and, although the small collection building in our case study achieved higher annual collection volumes, the smart bin nevertheless maintained a clear per-kilogram advantage. Additionally, smart bins demonstrated minimal end-of-life (EoL) impact due to their high recyclability, leaving the small building with a poor EoL environmental performance resulting from emissions linked to the building demolition. This study offers valuable insights for policymakers and stakeholders, emphasizing the potential of smart bins to enhance sustainability in e-waste collection.

Out-of-warranty repair of small household appliances remains limited due to high labour costs, spare part barriers, and low consumer willingness to pay for repair. This study introduces the Hobby Repair model, a structured approach that enables skilled individuals to repair products for modest compensation. Using a designbased research methodology, three field trials conducted in Belgium between 2022 and 2026 evaluated four operational sub-models ranging from independent repair to reuse store partnerships. Across all trials, 165 products were processed, achieving a 70% repair success rate and & euro;15,550 in revenue. Results show that organisational configuration strongly influences repair viability: institutionally supported models achieved higher stability, success rates, and financial performance than independent pathways. Results indicate that hobby-based repair can expand repair capacity for low-value appliances that are typically excluded from professional repair markets, providing a scalable complementary pathway within circular economy systems.

Titanium’s exceptional strength-to-weight ratio and corrosion resistance make it critical in aerospace, biomedical, and energy industries, yet its production is energy-intensive and environmentally challenging due to complex processing steps. This study investigates the environmental performance of an innovative recycling route that enables the production of solid Ti6Al4V components directly from machining chips through integrated sintering and forging steps. The assessment, conducted using the Environmental Footprint, Cumulative Energy Demand, and IPCC Global Warming Potential methods, reveals a substantial 85.8% reduction in overall environmental impact compared to conventional manufacturing, largely attributed to the elimination of titanium sponge production. The process requires 75.9 MJ of energy and emits 3.1 kg CO2-eq per kilogram of finished part, with the sintering step identified as the primary hotspot, driven mainly by electricity consumption and its effect on the ‘Fossil resource use’ category. Scenario modeling indicates that reducing the dwell time at 1200 °C from 30 min to 5 min decreases density slightly (from 99.9% to 99.8%) while lowering environmental impact by 23.5%. In contrast, decreasing the sintering temperature to 950 °C (30 min dwell) reduces density to 99.3% but achieves only a 4.8% impact reduction. A hypothetical shift to a cleaner electricity mix with 36% more renewables further reduces overall impacts by 20.8%, reinforcing the process’s potential as a sustainable alternative for titanium manufacturing.

Laser cutting of thick metal plates is often constrained by low cutting speeds and quality-related challenges, such as the formation of dross attachments along the cut edge. To address these limitations, several strategies have been developed, including increasing laser power, applying various laser beam shaping techniques, and optimizing assist gas configurations. In the present study, the combined effect of dynamic beam shaping and a mixed assist gas composition (nitrogen containing a low concentration of oxygen) is investigated for the first time. The study examines how this combined approach influences both the maximum achievable cutting speed and the dross formation. The resulting performance is systematically compared with previously established techniques, including static-beam oxygen cutting, static-beam nitrogen cutting, static-beam mixed gas cutting, and dynamic-beam nitrogen cutting. Cutting experiments performed on 10 mm and 12 mm-thick mild steel demonstrate that the synergy of dynamic beam shaping and mixed assist gas enables the production of dross-free cut edges at higher cutting speeds than those achievable with conventional static-beam oxygen cutting. These findings indicate that the combined strategy not only mitigates common quality issues but also enhances process efficiency, offering a promising direction for high-performance laser cutting of thick steel plates.

This paper analyses two structured adaptations of the Repair Café (RC) model developed by Maakbaar Leuven in Belgium: the Herstel Hub Elektro, a weekly appointment-based community repair service, and Corporate Repair Cafés (CRCs), a repair café organised by companies for employees. Both initiatives target small appliances that are often uneconomical to repair commercially, aiming to improve the predictability and financial viability of RCs. The Herstel Hub, launched in 2024, used one-hour appointments, a €25 contribution, and a mix of paid and volunteer repairers. Between February 2024 and August 2025, it hosted 75 sessions, repaired 234 devices with a 42% success rate, and showed that failed repairs often took as long as successful ones. CRCs were piloted at two enterprises, where employees accessed free on-site repairs during work hours, supported by at least one compensated repairer. Across five events, 109 devices were assessed, with 41% fixed and 43% deemed end of life. Compared with global RC data, which shows a 53% average fix rate, both models delivered slightly lower repair success rates, yet improved accessibility and potential scalability. These results illustrate how hybrid initiatives can bridge the gap between costly professional repair and volunteer-led activities, and they highlight design trade-offs for scalable community repair.

This study evaluates the environmental impact of using nickel-free stainless steel powder for producing medical implants, focusing on additive manufacturing (AM) of stabilizer brackets used in the Nuss-bar procedure. Currently, titanium-based implants produced via CNC milling form the alternative for nickel-allergic patients, but their production is associated with high environmental impact. A comparative life cycle assessment (LCA) was conducted on three production routes: CNC-milled titanium, electron beam melted (EBM) titanium, and laser powder bed fusion (LPBF) of a nickel-free stainless steel. The results demonstrate that LPBF of the nickel-free alloy significantly reduces CO2 emissions (by 69

Titanium alloys combine strength, low weight, and corrosion resistance, making them vital in high-performance industries; yet machining generates substantial chips that is difficult to recycle via conventional remelting due to contamination and high energy requirements, reducing material sustainability. Solid-state recycling methods, like Shear Assisted Processing and Extrusion (ShAPE), provide a promising alternative by consolidating chips below the melting point while preserving alloy chemistry. This study assesses the environmental performance of ShAPE across a system boundary spanning degreasing through consolidation and extrusion. Impacts were quantified using Cumulative Energy Demand (CED), Global Warming Potential, Environmental Footprint, Average Dissipation Rate (ADR), and Lost Potential Value (LPV), with ADR and LPV applied for the first time to solid-state recycling of scrap from discrete manufacturing. Scenario analyses addressed variations in torque, argon consumption, and electricity mix. Energy demand and CO 2 -eq for the ShAPE process were estimated at 279.51-567.75 MJ and 17.22-32.35 kg per kg of wire, respectively, with sensitivity analysis showing that variations in torque constitute the dominant determinant of these environmental outcomes. While energy demand is comparable to, or moderately lower than, that of traditional wire fabrication only under low-and baseline-torque conditions, ShAPE substantially reduces the resource dissipation and lost material values, with its overall environmental impacts further decreasing by 45.45% when powered with greener electricity. These results highlight ShAPE as a viable route for circular titanium production, preserving material value & reducing dependence on primary extraction.

This study investigates a hybrid manufacturing route combining heat-assisted Single Point Incremental Sheet Forming (SPIF) with Tungsten Inert Gas welding (TIG)-based material deposition for the local reinforcement of Mg–Zn–Zr (ZK61) alloy thin sheets. Flat and curved substrates extracted from SPIF-formed geometries were used to examine the influence of substrate thickness, forming temperature, and geometry on TIG deposition morphology and thermal distortion. The results indicate that heat input and substrate thickness strongly affect deposition morphology and dimensional stability, while SPIF sheet forming temperature influences the repeatability of the deposition process. In addition, deposition behavior exhibited limited sensitivity to substrate curvature for single depositions, whereas successive depositions resulted in increased thermal distortion due to cumulative residual stresses. Overall, this work identifies key process sensitivities and constraints associated with TIG deposition on SPIF-formed magnesium alloy sheets, providing a basis for the development of hybrid forming-deposition process chains for localized reinforcement applications.

The accumulation of electronic waste (e-waste) poses growing environmental challenges, amplified by the release of toxic brominated compounds in traditional recycling approaches. Printed circuit boards (PCBs), a key component of e-waste, provide an opportunity for resource recovery through advanced mechanical separations. This study evaluates the environmental performance of a developed mechanical separation process for PCBs using the Environmental Footprint 3.1, IPCC Global Warming Potential, and Cumulative Energy Demand methods. The analyzed process attempts to recover enriched outputs, including a copper concentrate and an epoxy and ceramics concentrate, aiming at delivering an efficient metals recovery, producing phenolic derivatives, and reducing bromine emissions in downstream materials recovery. Results reveal that 7–12% of the initial waste PCBs is liberated as an epoxy-rich concentrate, which, alongside the copper fraction, demonstrates potential for impact mitigation across the recycling chain. However, the process requires a cumulative energy demand of 1658.7 MJ and emits 99.9 kg CO2-eq per ton of PCBs. Size reduction was identified as the most energy-intensive step, due to the high energy demand of millimeter-scale material reduction needed for the inertial and electrostatic separations. Sensitivity analysis highlighted the influence of regional energy profiles, with a lower dependence on fossil-based electricity significantly reducing impacts. The study also noted the disproportionate impact of recovered materials, with the copper concentrate showing a high price-weighted CO2-eq of 0.28 kg and 4.6 MJ energy demand per kg of liberated copper concentrate. The environmental impact per unit of economic gain for the copper concentrate evolves over the process to an order of magnitude higher than that of the initial input, with transportation dominating the impact. These findings emphasize the potential of advanced mechanical separation to address e-waste concerns, while identifying areas for improvement toward a more sustainable recycling framework.

Grinding, a common finishing process, relies on grinding wheels that, once worn out, are often discarded in landfills, contributing to environmental concerns due to their non-biodegradable composition. A sustainable alternative end-of-life solution involves repurposing the abrasive component, like alumina, from grinding wheels waste as feedstock for abrasive waterjet cutting (AWJC), traditionally using virgin garnet, whose environmental impact is considerable due to its reliance on raw material extraction. This study assesses the environmental impact of using recycled alumina abrasives derived from grinding wheel waste as a substitute for virgin garnet in AWJC, analyzing two treatment methods, mechanical and chemical separations, using existing literature data. Results show that replacing virgin garnet in the AWJC with recycled alumina achieves a reduction in the AWJC overall impact by 35-38%, as per the ReCiPe 2016 method, with the highest reduction observed in the ‘mineral resource scarcity’ category. The virgin garnet’s impact predominantly stemmed from mining and transport, accounting for around 61% and 39%, respectively, assuming a cutting process located in Belgium. In all scenarios, higher abrasives’ reusability consistently enhanced environmental performance, with the effect being particularly pronounced in garnet-utilized cutting process due to the diminished need for garnet mining. Despite recycled alumina’s higher energy demand for size reduction, the environmental gains from substitution were marginally influenced, underscoring virgin garnet’s significant role in the AWJC impact. This study emphasizes opportunities for sustainable manufacturing by fostering industrial symbiosis, thereby enhancing resource conservation and environmental sustainability.

This paper proposes a circular economy business model for recycling and remanufacturing Bosch Gen 3 batteries to enhance sustainability and economic viability. The model integrates collection, robotic disassembly, and state-of-health-based categorisation to extract the most valuable, reusable cells and then tests a battery remanufacturing option to maximize profit and critical raw material recovery. Two collection methods are analysed: incentivized returns (Option 1) and battery waste sorting at recycling centres (Option 2). A Monte Carlo simulation evaluates profitability with several uncertainties, including logistics and deposit refunds. Option 1 is more likely to obtain higher-quality cells, but is less likely to be profitable due to the high costs associated with the incentive, while Option 2 is more cost-effective, but yields lower-quality cells. This study highlights opportunities to optimize incentives and recycling value, providing a scalable framework for sustainable battery end-of-life management.

The growing e-waste from household appliances, particularly washing machines, highlights the need for improved repairability and durability solutions. The "Internet of Washing Machines" (IoW) project addressed this challenge by developing a manufacturer-agnostic monitoring module and a supporting cloud-based system designed to assist repair. Through a pilot study in citizen scientists’ homes, a non-invasive sensor module was developed which monitored key parameters such as vibration, electrical current, and water consumption to enable advanced remote diagnosis. Integrated into an open-source platform, the IoW system showed potential to improve diagnostic accuracy, reduce second visits, and minimize wasted repair trips. Preliminary analysis suggests that the system could allow repair technicians to serve 767 additional clients annually, with an average service time of 43 minutes per client, resulting in a 38% improvement in efficiency. However, deployment challenges, including weak Wi-Fi and sensor inaccuracies, limited data collection. Furthermore, the cost-benefit ratio proved challenging, with €5 in savings per customer compared to the €70 prototype cost. Despite these limitations, features such as cost-per-cycle monitoring, cycle-based warranties, and preventative maintenance could enhance the system’s value and support more sustainable repair practices.

The fraction of materials that does not reach the target product in discrete manufacturing is very significant. Directing secondary material streams towards other manufacturing processes, possibly after intermediate pre-processing, offers opportunities for more energy and resource efficient recycling routes. This paper contributes to the exploration of such symbiotic recycling strategies by identifying relevant process mechanisms and by systematically scanning the manufacturing domain for relevant process combinations. Emerging and proven symbiotic combinations within the discrete manufacturing domain are reviewed, with proper attention for the quantification of the thus avoided environmental impact. A series of representative case studies illustrates the feasibility of applying industrial symbiosis principles in a discrete manufacturing context, with uniform data sheets providing detailed information on relevant research achievements.

This study delves into the static and dynamic load testing of 3D-printed gears, addressing the potential of utilizing FDM 3D printing for repairing household appliances. The failure of electronic household appliances attributed to plastic gear malfunction has prompted an alarming number of products to be prematurely discarded due to a lack of available spare parts. The research emphasizes the transformative potential of 3D printing to streamline gear repairs, enabling rapid local production of gear replacements, and reducing costs and downtimes associated with conventional spare parts. PLA and ABS, the two most widely used 3D printing materials, underwent exhaustive static tests to determine maximum load-bearing capacities and accelerated fatigue tests to assess long-term performance. Results underscore the potential of the 3D printing process itself, highlighted by flexibility and shortened production timelines. However, limitations arise from the inferior mechanical properties of PLA and ABS as compared to traditional plastic gear materials such as nylon. PLA demonstrates promise under controlled temperatures but only with lubrication or metal contact, while ABS reveals inadequate mechanical and fatigue characteristics at higher torques.

Making threaded connections to thin metal sheets requires locally thickening of the sheet in order to provide enough thread length for a structurally sound connection. Shaped Metal Deposition processes like Gas Tungsten Arc Welding (GTAW) allow to locally build-up material in order to provide thickness for a sufficient length of thread engagement. This publication describes the research towards local thickening of a titanium sheet by means of pulsed Tungsten Inert Gas (TIG) droplet deposition, aimed at creating threaded holes for thin shelled bone fracture fixation plates. The influence of current, weld time and amount of filler material on droplet diameter and height is studied.

This study focuses on finding a toolpath strategy for accurately forming geometric details on a preshaped sheet metal part by incremental forming in multiple steps. The final thickness distributions and geometrical accuracy are analyzed for spiraling and dedicated feature toolpath strategies. The results are compared to forming the full part (base shape with details) in a conventional single stage manner. Forming the part in multiple steps did improve the accuracy of the part, by decreasing the underforming of the base shape compared to single stage forming. The observed overforming was highly influenced by the location of the detail. In terms of thickness distributions, the toolpath strategy highly influenced the location of the minimal thickness inside each detail. Here, the dedicated feature toolpath proved to be effective for achieving a more uniform thickness distribution.

In the light of the anticipated emergence of a surplus of highly alloyed scrap in the near future, this article investigates the impact of alternative scrap treatment strategies that mitigate the quality losses that characterise the currently dominant downcycling approach. The environmental impact of the current downcycling strategy is compared to three other strategies to treat post-consumer aluminium scrap. Two electrolytic refining strategies are considered that can remove accumulated alloying elements and impurities from the aluminium scrap. This is one way to substitute more primary aluminium by scrap than what is possible in the downcycling approach. The considered electrolytic processes are the traditional Hoopes refining process and a novel low-energy variant. The fourth considered strategy is enhanced sorting of the post-consumer aluminium scrap by Laser-Induced Breakdown Spectroscopy (LIBS), a proven technology that can separate the aluminium scrap by alloy group, enabling as such more wrought-to-wrought recycling. The results of the assessment show that each of these three alternative strategies yields significant environmental benefits with respect to the common downcycling approach. By 2030, implementing the traditional Hoopes strategy, the low-energy Hoopes strategy or the LIBS sorting strategy would reduce the aggregated environmental impact with 1.5%, 5.5% or 15.9%, respectively. This result offers a strong argument in favour of adopting novel scrap sorting processes.

Many methods and tools have been developed to help original equipment manufacturers to shift towards circular business models (CBM), however, a gap is observed for decision making support that allows to test different functions of a CBM (e.g., product design and financial and environmental assessment) and their prompt exchange of relevant information. To overcome this, a design platform concept is proposed, aiming to transcend existing frameworks’ limitations and link engineering and managerial aspects. Focused on delivering Product-as-a-Service for electrical and electronic equipment, the platform concept aims to reduce global electronic waste and extend product lifespans. The framework proposed involves a holistic approach encompassing product architecture, service ecosystems, and new digital technologies. Emphasis is placed on a hierarchical product architecture structure, a well-developed service ecosystem involving various stakeholders, and the integration of digital twins, data management, and artificial intelligence. Specific performance and circularity indicators within the design platform concept will address the challenges related to circularity, business model development, and sustainability. These indicators encompass decision tools focusing on both product and business model design and operation with the help of different ease of X decision tools (repair, refurbish, remanufacture, reuse, and recycle). Additionally, sustainability validation tools, including life cycle assessment, critical raw material assessment, life cycle cost analysis, and social life cycle assessment, will support informed decision-making within the design platform concept.