Purpose

This study aims to evaluate and compare the macroscopic properties of commercial acrylonitrile-butadiene-styrene (ABS) processed by two different types of additive manufacturing (AM) machines. The focus is also on the effect of multiple closed-loop recycling of ABS.

Design/methodology/approach

A conventional direct-drive, Cartesian-type machine and a Bowden, Delta-type machine with an infrared radiant heating system are used to manufacture test specimens molded in ABS. Afterward, multiple closed-loop recycling cycles are conducted, involving consecutive AM (four times) and recycling (three times). The rheological, mechanical, morphological and physicochemical properties are investigated.

Findings

The type of machine affects the quality of the produced parts. The machine containing an infrared radiant system in a temperature-controlled chamber produces parts showing higher mechanical properties and filling fraction, although it increases the yellowing. Closed-loop recycling of ABS for AM is applicable for at least two cycles, inducing a slight increase in tensile modulus (ca. 5%) and in tensile strength (ca. 13%) and a decrease in the impact strength (ca. 14%) and melt viscosity. An increase in the filling fraction of the AM parts promotes an increase in tensile strength and tensile modulus, although it does not influence the impact strength. Furthermore, multiple closed-loop recycling does not affect the overall chemical structure of ABS.

Practical implications

Controlling the environmental temperature and using infrared radiant heating during AM of ABS improves the quality of the produced parts. Closed-loop recycling of ABS used in AM is feasible up to at least two recycling steps, supporting the implementation of a circular economy for polymer-based AM.

Originality/value

This study shows original results regarding the assessment of the effect of different types of AM machines on the main end-use properties of ABS parts and the influence of multiple closed-loop recycling on the characteristics of ABS fabricated by the most suited AM machine with an infrared radiant heating system and a temperature-controlled environment.

中文翻译：

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机器类型和连续闭环再循环对丙烯腈-丁二烯-苯乙烯零件熔丝制造宏观性能的影响

目的

这项研究旨在评估和比较由两种不同类型的增材制造（AM）机器加工的商业丙烯腈-丁二烯-苯乙烯（ABS）的宏观性能。重点还在于ABS的多个闭环再循环的效果。

设计/方法/方法

常规的直驱直角笛卡尔型机器和带有红外辐射加热系统的鲍登三角洲型机器用于制造用ABS模制的试样。之后，执行多个闭环循环，包括连续的AM（四次）和循环（三次）。研究了流变，机械，形态和物理化学性质。

发现

机器的类型会影响所生产零件的质量。尽管该机器增加了泛黄性，但在可控温度的腔室中装有红外辐射系统的机器所产生的零件仍具有较高的机械性能和填充率。用于AM的ABS的闭环循环至少适用于两个循环，从而导致拉伸模量（约5％）和拉伸强度（约13％）略有增加，并且冲击强度（约14％）降低％）和熔体粘度。AM零件的填充率增加，虽然不会影响冲击强度，但会促进拉伸强度和拉伸模量的增加。此外，多次闭环再循环不会影响ABS的整体化学结构。

实际影响

在ABS的增材制造过程中控制环境温度并使用红外辐射加热可提高所生产零件的质量。增材制造中使用的ABS的闭环再循环至少在两个再循环步骤之前都是可行的，从而支持实现基于聚合物的增材制造的循环经济。

创意/价值

这项研究显示了关于评估不同类型的AM机器对ABS零件的主要最终用途性能的影响以及多重闭环再循环对最合适的AM机器制造的ABS特性的影响的原始结果。红外辐射加热系统和温度受控的环境。