晶体质感在3D打印聚乙烯反应堆混合物中的演变
Sahitya Movva1,2, Carl G Schirmeister3,4, Timo Hees3
1School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States.
ACS omega
|May 20, 2024
概括
聚乙烯混合物的3D打印显示出比注塑更大的纹理演变和异构性. 打印速度和方向显著影响材料特性,与分子重量相比,对异性质有更好的控制.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物科学 聚合物科学
- 晶体学 晶体学是指结晶学.
背景情况:
- 3D打印允许量身定制的材料特性,但其晶体结构的演变需要与传统方法进行比较.
- 聚乙烯 (PE) 混合物,包括高密度PE (HDPE),超高分子量PE (UHMWPE) 和HDPE_wax,用于增材制造和注塑.
- 了解结晶体的方向对于预测和控制材料异质性至关重要.
研究的目的:
- 为了研究和量化3D打印的三模体PE混合物中的晶体纹理演变,与注塑 (IM) 样品相比.
- 分析3D打印工艺参数 (速度,方向) 和材料参数 (分子量) 对纹理和异质的影响.
- 为了比较3D打印与IM在量身定制材料异构性方面的有效性.
主要方法:
- 广角X射线衍射 (WAXD) 用于分析极点图和方向分布函数 (ODF).
- 通过3D打印和IM处理了具有不同重量-平均分子量 (Mw) 的三极管PE混合物.
- 系统地改变了3D打印参数,包括与打印轴相对的速度和样品方向.
主要成果:
- 3D打印样品,特别是在0°打印方向下,表现出比类似吞吐量的IM样品更大的纹理演变和更高的异构性.
- 增加的3D打印速度通过沿着打印方向对齐晶体来增强异构性.
- 与0°打印方向的偏差导致同位素性增加,而Mw的变化对异位素性的影响与打印参数相比较不那么大.
结论:
- 与注塑成型相比,3D打印在PE混合物中提供了对晶体纹理和材料异性质的优越控制.
- 打印速度和方向是定制3D打印PE材料中异性质性质的关键参数.
- 该研究强调了增材制造在制造具有精确工程定向性质的材料方面的潜力.
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