Sustainable Additive Manufacturing

可持续增材制造

• 批准号: EP/W01906X/1
• 负责人: Stewart Williams
• 金额: $ 212.18万
• 依托单位: CRANFIELD UNIVERSITY
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FW01906X%2F1
• 关键词: Sustainable; Additive; Manufacturing

It is usually energy intensive and expensive to manufacture high performance and high-value materials, such as titanium alloys. The total energy required is typically more than 600 MJ to get each kg to get the semi-finished Ti products (ingots), with more than 36 kg CO2 carbon footprint. During the subsequent manufacturing stage, mainly subtractive manufacturing (SM) process, a large amount of Ti alloy scrap is generated in the form of swarf and chips (can be up to 95% of the initial Ti ingot) which is far greater than that of the final Ti products. High-grade swarf (with lower O and Fe) is usually recycled downstream to the melting stage for ingots which requires about 225MJ/kg to convert it to wire. Or it can be directly converted into billets using solid state processing methods, such as Confrom, Fastforge, and ECAP, however, they have limitations and challenges for titanium alloy, such as low properties, and sever tool wear. Often, they produce semi-finished products, so further processing into wire or powder is required before they can be used in AM, which usually includes another melting step. Studies have shown that a remarkable reduction in energy consumption and CO2 emission can be achieved by using additive manufacturing (AM). Compared to SM, AM improves the material usability efficiency greatly due to the near or very near shape component production with just minor finishing steps required. Using swarf as feedstock in AM will have a major impact on the economics of AM, which can be more expensive than SM, currently restricting its application and concomitant material and emissions savings. A high Buy-to- Fly (BTF) ratio for SM process needs to be significantly greater than the ratio of the wire cost to the semi-finished product cost for AM to be economically justifiable. Using swarf, the cost of AM will be drastically lowered, which will lead to much more widespread adoption of AM, allowing other important gains to be exploited, including material, energy, and emission savings, and component lead timesTherefore, our research vision is Novel metal AM processes that utilise recycled swarf as feedstock, enabling a greatly reduced overall energy and CO2 footprint for high-value near-net-shaped components, and facilitating much wider exploitation of near-net-shape AM technologies throughout industry.To deliver this vision, a new method which facilitate a skin and core concept. The outer skin will be deposited using virgin material, with high resolution providing accurate geometric definition and a smooth outer surface, leading to a near-net shape component. The core will be in-filled with pre-processed high-grade swarf, in a solid/ liquid form, which may be mixed with virgin wire to control oxygen levels. In-situ mechanical work will be applied to control defects and improve the material properties. The research will comprise activities on input swarf material characterisation, process development, material output characterisation, process modelling, SAM concept validation, and environmental and economic assessment. SAM will contribute to the 'net-zero' strategy of the UK. It will also provide wider academic impact as many techniques and tools developed will be of direct relevance and great benefit to other AM and related technologies.

制造高性能、高价值的材料，如钛合金，通常是能源密集型和昂贵的。获得每公斤钛半成品(钢锭)所需的总能量通常超过600MJ，二氧化碳排放量超过36公斤。在随后的制造阶段，主要是减法制造(SM)过程，大量的钛合金废料以切屑和切屑的形式产生(最高可达初始钛锭的95%)，远远超过最终的钛产品。高品位的碎屑(含较低的O和Fe)通常被回收到钢锭的熔化阶段，这需要大约225MJ/kg才能将其转化为钢丝。也可以通过Confrom、Fastforge和ECAP等固态加工方法直接转化为坯料，但这些方法对钛合金具有局限性和挑战性，如性能低、刀具磨损严重等。通常，它们会生产半成品，因此需要进一步加工成线材或粉末，然后才能用于AM，这通常包括另一个熔化步骤。研究表明，使用添加剂制造(AM)可以显著降低能源消耗和二氧化碳排放。与SM相比，AM只需较小的精加工步骤即可生产出接近或非常接近形状的部件，从而大大提高了材料的使用效率。在AM中使用SWARF作为原料将对AM的经济性产生重大影响，AM的成本可能比SM更高，目前限制了其应用以及伴随的材料和排放节约。SM工艺的高买飞(BTF)比率需要显著大于AM的线材成本与半成品成本的比率，才能在经济上合理。使用swarf，AM的成本将大大降低，这将导致AM更广泛地被采用，允许开发其他重要的收益，包括材料、能源和排放节约，以及组件提前期。因此，我们的研究愿景是新型金属AM工艺，利用回收的碎屑作为原料，使高价值近净形状组件的总体能源和二氧化碳足迹大大减少，并促进整个行业更广泛地利用近净形状AM技术。外层皮肤将使用原始材料沉积，具有高分辨率，提供准确的几何定义和平滑的外表面，导致近净形状组件。堆芯将填充以固体/液体形式预先处理的高级碎屑，这些碎屑可能会与原始金属丝混合，以控制氧气水平。将采用原位机械加工来控制缺陷，改善材料性能。研究将包括关于输入碎片材料特性、过程开发、材料输出特性、过程建模、SAM概念验证以及环境和经济评估的活动。萨姆将为英国的“净零”战略做出贡献。它还将提供更广泛的学术影响，因为开发的许多技术和工具将对其他AM和相关技术具有直接相关性和巨大好处。