A direct 3D extrusion printing technique was used to produce Ti-TiB filaments and microlattices.The sintering properties of 3D ink extrusion and sintering of in situ Ti-TiB composite structures made from TiH_(2)+TiB_(...A direct 3D extrusion printing technique was used to produce Ti-TiB filaments and microlattices.The sintering properties of 3D ink extrusion and sintering of in situ Ti-TiB composite structures made from TiH_(2)+TiB_(2) ink were investigated.The sintering kinetics of TiH2+TiB2 inks was studied during densification by pressureless sintering at 1050−1200℃ for 4−24 h in Ar.The linear shrinkage,grain size,microhardness,X-ray diffraction(XRD)patterns,and microstructural evolution of the Ti-TiB composite were studied.The sintering temperature had a more pronounced influence than the sintering time on the density of the Ti-TiB composite.There were two kinds of pores,irregular and spherical,caused by the Kirkendall effect and indiffusable gases.The TiB formed by in situ synthesis existed as either separated TiB whiskers(needle-like shapes)or clusters of TiB whiskers.The results of this work could be useful for controlling microporosity through incomplete sintering within filaments,especially for the production of in situ Ti-TiB with high volume fractions of TiB or other composites.展开更多
将3D打印技术应用于电活性聚合物材料—离子凝胶材料,采用离子凝胶的材料热压工艺所用的溶液配置方法,重点研究了在不同流量、不同扫描速度组合下,离子凝胶芯层与电极层单点成线、线拼成面后特征尺寸分布规律。实验结果表明:挤出流量的...将3D打印技术应用于电活性聚合物材料—离子凝胶材料,采用离子凝胶的材料热压工艺所用的溶液配置方法,重点研究了在不同流量、不同扫描速度组合下,离子凝胶芯层与电极层单点成线、线拼成面后特征尺寸分布规律。实验结果表明:挤出流量的和扫描速度影响单点成线的线宽数值大小,进而影响线拼成面的单层质量。在得到单层质量最佳工艺参数及单层层厚参数的基础上,以圆柱环为例,通过多层叠加打印了厚度为0.5 mm的离子凝胶立体结构,给该结构的测点该施加500 m N的压力,该结构上下表面可产生0.35 m V的电压;采用复合打印技术制造出了离子凝胶的三明治结构,将打印出来的离子凝胶试件在3.5 V的直流电压下驱动,该试件末端18 s内可以发生1.5 mm的变形,传感驱动性能测试结果证明离子凝胶三维打印工艺可行,从而为后续该材料的复杂结构制造以及在软体机器人中的应用奠定基础。展开更多
In this study,a high impact resistant multi-layered composite consisting of continuous carbon fibre/nylon(CCF)and short carbon fibre/nylon(SCF)layers is developed via 3D printing technology.The effect of CCF/SCF layer...In this study,a high impact resistant multi-layered composite consisting of continuous carbon fibre/nylon(CCF)and short carbon fibre/nylon(SCF)layers is developed via 3D printing technology.The effect of CCF/SCF layers configuration on the impact resistance is investigated by low-velocity impact test,and the impact failure mechanism of the 3D printed composites is explored by microscopic observations and finite element(FE)simulation analysis.The results show that the 3D printed multi-layered composite with SCF layers distributed in the middle(HFA)exhibits higher impact resistant performance than the specimens with alternating SCF/CCF layers(HFB)and CCF layers distributed in the middle(HFC).The effect of CCF/SCF layers proportion on the impact performance is also studied by FE simulation,and the results show that the specimen with a CCF/SCF proportion of 7.0 exhibits the highest impact strength.展开更多
基金Project(201806920003)supported by the China Scholarship CouncilProject(172180)supported by the Swiss National Science FoundationProjects(ECCS-1542205,DMR-1720139)supported by the National Natural Science Foundation,USA。
文摘A direct 3D extrusion printing technique was used to produce Ti-TiB filaments and microlattices.The sintering properties of 3D ink extrusion and sintering of in situ Ti-TiB composite structures made from TiH_(2)+TiB_(2) ink were investigated.The sintering kinetics of TiH2+TiB2 inks was studied during densification by pressureless sintering at 1050−1200℃ for 4−24 h in Ar.The linear shrinkage,grain size,microhardness,X-ray diffraction(XRD)patterns,and microstructural evolution of the Ti-TiB composite were studied.The sintering temperature had a more pronounced influence than the sintering time on the density of the Ti-TiB composite.There were two kinds of pores,irregular and spherical,caused by the Kirkendall effect and indiffusable gases.The TiB formed by in situ synthesis existed as either separated TiB whiskers(needle-like shapes)or clusters of TiB whiskers.The results of this work could be useful for controlling microporosity through incomplete sintering within filaments,especially for the production of in situ Ti-TiB with high volume fractions of TiB or other composites.
文摘将3D打印技术应用于电活性聚合物材料—离子凝胶材料,采用离子凝胶的材料热压工艺所用的溶液配置方法,重点研究了在不同流量、不同扫描速度组合下,离子凝胶芯层与电极层单点成线、线拼成面后特征尺寸分布规律。实验结果表明:挤出流量的和扫描速度影响单点成线的线宽数值大小,进而影响线拼成面的单层质量。在得到单层质量最佳工艺参数及单层层厚参数的基础上,以圆柱环为例,通过多层叠加打印了厚度为0.5 mm的离子凝胶立体结构,给该结构的测点该施加500 m N的压力,该结构上下表面可产生0.35 m V的电压;采用复合打印技术制造出了离子凝胶的三明治结构,将打印出来的离子凝胶试件在3.5 V的直流电压下驱动,该试件末端18 s内可以发生1.5 mm的变形,传感驱动性能测试结果证明离子凝胶三维打印工艺可行,从而为后续该材料的复杂结构制造以及在软体机器人中的应用奠定基础。
基金This work was supported by the National Science Fund for Distinguished Young Scholars(Grant No.11625210)the National Science Foundation of China(Grant No.51873153)+1 种基金the Shanghai Pujiang Program(Grant No.19PJ1410000)the Shanghai International Science and Technology Cooperation Fund Project(Grant No.19520713000).
文摘In this study,a high impact resistant multi-layered composite consisting of continuous carbon fibre/nylon(CCF)and short carbon fibre/nylon(SCF)layers is developed via 3D printing technology.The effect of CCF/SCF layers configuration on the impact resistance is investigated by low-velocity impact test,and the impact failure mechanism of the 3D printed composites is explored by microscopic observations and finite element(FE)simulation analysis.The results show that the 3D printed multi-layered composite with SCF layers distributed in the middle(HFA)exhibits higher impact resistant performance than the specimens with alternating SCF/CCF layers(HFB)and CCF layers distributed in the middle(HFC).The effect of CCF/SCF layers proportion on the impact performance is also studied by FE simulation,and the results show that the specimen with a CCF/SCF proportion of 7.0 exhibits the highest impact strength.
