First Time Concrete: Integrated digital models for right-first-time 3D concrete printing and milling

首次混凝土：首次成功的 3D 混凝土打印和铣削集成数字模型

• 批准号: EP/X02430X/1
• 负责人: Peter Kinnell
• 金额: $ 129.86万
• 依托单位: Loughborough University
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FX02430X%2F1
• 关键词: First; Time; Concrete; Integrated; digital

Concrete is one of the most widely used materials in the world. For many years traditional processes have been used to make concrete parts. However, over the last decade, 3D printing has revolutionised the way concrete parts are made. Complex concrete parts can now be created with no formwork or mould tooling. This is important as it removes the time and expense associated with making the moulds, but critically it also offers the potential to create parts that are structurally optimised to maintain strength with less material. This brings benefits in terms of cost but also it represents a significant environmental benefit as less material is needed, so carbon dioxide equivalent emissions are also reduced. The process is still in development though, and current 3D printing processes result in geometric forms and surface finishes that are not always desirable, and part accuracy that is too low for many applications. To address this, the 3D printing process can be followed immediately by a subtractive process that mills the surface to trim off unwanted material. This improves both accuracy and surface finish. By using a two-stage process of deposition followed by milling, it is possible to create high-quality parts, with intricate features and well-controlled surface finishes. The problem is that for each new part manufactured in this way, many iterative process development trials are required to perfect the deposition and milling strategy. This is time-consuming and wasteful, and it is a barrier to the uptake of the technology. The First Time Concrete (FT-Concrete) project will address this problem by creating new digital process and material models that can be used to help design printing and milling strategies without the need for physical trials. To do this, these models will be coupled within a digital workflow that enables optimised process design of both the material deposition and the milling process together. So, for a given part the feasibility of defect free manufacturing can be assessed, and the part or process design can be optimised, to ensure parts are printed right first time. This will be a two-way process, where printing sequence, speed and geometry will be optimised to suit milling requirements and vice versa.To achieve this the FT-Concrete project will investigate new time-dependent material properties models that can predict the curing state and optimal milling window and milling parameters for every position in a part. These must account for the variability of the mix, ambient conditions, printing sequence and the shape of the printed parts. New complementary process models for milling 3D printed concrete in a 'green' state will also be created. These must be able to cope with the highly variable material properties inherent to curing concrete. Finally, these new models will be integrated within a digital design system that will reduce, or potentially remove, the need for physical prototype parts. The new digital process and material models that we envisage, together with a digitally coupled design process will have significant commercial value; as they have the potentially to reduce process development time, material waste, and cost. We believe this could unlock 3D concrete printing to a wide range of new applications, boosting the uptake of the technology. Enabling structures and geometries that are currently impossible to produce. To pave the way for the uptake of these models, our aim is to integrate them within freely available, opensource, 3D printing design software. In addition, we will work with industrial partners to demonstrate the potential of the digital approach through industrially driven case studies.

混凝土是世界上使用最广泛的材料之一。多年来，传统工艺一直用于制造混凝土部件。然而，在过去的十年中，3D打印已经彻底改变了混凝土部件的制造方式。复杂的混凝土部件现在可以创建没有模板或模具工具。这很重要，因为它消除了与制造模具相关的时间和费用，但关键的是，它还提供了创建结构优化的部件的可能性，以便用更少的材料保持强度。这在成本方面带来了好处，但它也代表了显著的环境效益，因为需要更少的材料，因此也减少了二氧化碳当量排放。然而，该工艺仍在开发中，目前的3D打印工艺导致几何形状和表面光洁度并不总是理想的，并且对于许多应用来说零件精度太低。为了解决这个问题，3D打印过程之后可以立即进行减材过程，该减材过程对表面进行米尔斯研磨以修剪掉不需要的材料。这提高了精度和表面光洁度。通过使用沉积和铣削的两阶段工艺，可以制造出具有复杂特征和良好控制的表面光洁度的高质量零件。问题是，对于以这种方式制造的每个新零件，需要进行许多迭代的工艺开发试验，以完善沉积和铣削策略。这既费时又浪费，而且是吸收该技术的障碍。First Time Concrete（FT-Concrete）项目将通过创建新的数字工艺和材料模型来解决这个问题，这些模型可用于帮助设计打印和铣削策略，而无需进行物理试验。为此，这些模型将在数字工作流程中耦合，从而实现材料沉积和铣削过程的优化工艺设计。因此，对于给定的零件，可以评估无缺陷制造的可行性，并可以优化零件或工艺设计，以确保零件在第一次打印时就正确。这将是一个双向过程，打印顺序、速度和几何形状将根据铣削要求进行优化，反之亦然。为了实现这一目标，FT-Concrete项目将研究新的时间相关材料属性模型，该模型可以预测零件中每个位置的固化状态和最佳铣削窗口和铣削参数。这些必须考虑到混合物的可变性、环境条件、印刷顺序和印刷部件的形状。还将创建用于在“绿色”状态下铣削3D打印混凝土的新的补充工艺模型。这些必须能够科普固化混凝土固有的高度可变的材料特性。最后，这些新模型将被集成到一个数字设计系统中，这将减少或可能消除对物理原型部件的需求。我们设想的新的数字工艺和材料模型，以及数字耦合设计过程将具有重大的商业价值;因为它们有可能减少工艺开发时间，材料浪费和成本。我们相信这可以将3D混凝土打印解锁到广泛的新应用中，从而促进该技术的应用。实现目前无法生产的结构和几何形状。为了为这些模型的采用铺平道路，我们的目标是将它们集成到免费提供的开源3D打印设计软件中。此外，我们将与行业合作伙伴合作，通过行业驱动的案例研究来展示数字方法的潜力。