Purpose

With a growing list of available materials and processes, the inherent mechanical and thermophysical properties of three-dimensional (3D) prints are important design targets. This paper aims to study the functionality of binder jet 3D printed objects for thermally activated building construction elements and recyclable formwork for concrete structures.

Design/methodology/approach

Binder jet printed sand samples with various material and post-processing parameters (infiltration and baking) are prepared and studied. Using a statistical experiment design, the mechanical (flexural and compressive strength) and thermal (conductivity and specific capacity) characteristics are quantified.

Findings

Relative to the unprocessed “green” print samples, post-processing improved the flexural and compressive strength of the samples by factors of 6.9 and 21.6, respectively; the thermal conductivity and specific heat capacity were improved by factors of 7.7 and 1.2, respectively. For the investigated temperature range (20°C–200°C), the “green” prints showed excellent stability while the stability of post-processed samples depended on the infiltrate used. Microscopic images of the microstructures offered evidence to support improvement in the mechanical and thermo-physical characteristics of the 3D printed sand elements.

Research limitations/implications

The literature review concluded that optimal printing parameters and infiltration under vacuum could further improve the mechanical and thermo-physical properties of the binder jet printed elements. However, both these factors were not explored in this research. The statistical experimental design approach provided more flexibility to choose the number of experiments for a fixed amount of time and resources. However, for future work, a more extensive number of experiments and reproducibility testing for each combination of binder-infiltrate is recommended.

Practical implications

3D printing has been identified as a promising opportunity to reduce material usage and improve construction efficiency in the field of architecture and building engineering. The emerging fabrication technologies are further expected to significantly reduce the operational energy of buildings through performance integration, i.e. multi-functional building elements with integrated heat- and mass-transfer capabilities to replace conventional systems.

Originality/value

This study has quantified the impact of infiltration on the mechanical and thermo-physical characteristics of sand-printed elements and, as such, reports reproducible functional performance maps for sand-print applications. The research demonstrates a way to achieve the desired functional characteristics of 3D prints through combinations of material selection and process/post-processing parameters.

中文翻译：

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使用统计实验方法研究粘合剂喷射 3D 打印元件的机械和热物理特性

目的

随着可用材料和工艺的不断增加，三维 (3D) 打印的固有机械和热物理特性成为重要的设计目标。本文旨在研究粘合剂喷射 3D 打印物体的功能，用于热激活建筑构件和混凝土结构的可回收模板。

设计/方法/方法

制备和研究了具有各种材料和后处理参数（渗透和烘烤）的粘合剂喷射打印砂样品。使用统计实验设计，对机械（弯曲和抗压强度）和热（电导率和比容量）特性进行量化。

发现

相对于未经处理的“绿色”印刷样品，后处理使样品的抗弯强度和抗压强度分别提高了 6.9 和 21.6 倍；导热系数和比热容分别提高了 7.7 和 1.2 倍。对于研究的温度范围 (20°C–200°C)，“绿色”印刷品显示出出色的稳定性，而后处理样品的稳定性取决于所使用的渗透液。微观结构的显微图像为支持改进 3D 打印砂元件的机械和热物理特性提供了证据。

研究限制/影响

文献综述得出结论，最佳印刷参数和真空下的渗透可以进一步改善粘合剂喷射印刷元件的机械和热物理性能。然而，本研究并未探讨这两个因素。统计实验设计方法为在固定的时间和资源量下选择实验数量提供了更大的灵活性。然而，对于未来的工作，建议对每种粘合剂渗透组合进行更广泛的实验和再现性测试。

实际影响

3D 打印已被确定为在建筑和建筑工程领域减少材料使用和提高施工效率的有希望的机会。预计新兴制造技术将通过性能集成显着降低建筑物的运行能源，即具有集成传热和传质能力的多功能建筑元件以取代传统系统。

原创性/价值

这项研究量化了渗透对砂印元件的机械和热物理特性的影响，因此，报告了砂印应用的可重复功能性能图。该研究展示了一种通过材料选择和工艺/后处理参数的组合来实现 3D 打印所需功能特性的方法。