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The application of ceramic materials is limited due to the complicated preparation process and intrinsic brittleness. In this work, a pressureless manufacturing route that enables the formation of barium aluminosilicate (BAS) glass-ceramic consisting of internal β-Sialon fibers with enhanced thermal conductivity is developed. By adjusting the carbon source content, composites with different Sialon contents can be easily fabricated. The thermal conductivity of the sample with 3.5 wt.% is improved to 5.845 W/m ∙ K with the Sialon content of 26 wt.% in the composite, which is 112.64 % higher than that of the pure BAS matrix. The theoretical models suggest that the enhanced thermal conductivity is mainly ascribed to the thermal conduction network constructed by Sialon fibers. This work provides a method with industrial application prosperity to fabricate the high temperature ceramic matrix composite of different sizes and complex shapes.

Magnetic microhelix motors have been widely used in many fields such as cargo transportation, drug delivery, toxic substance declogging and cell manipulation due to their unique adaptive magnetic manipulation. In this work, we have additively manufactured microhelices with different circles, sizes and angles (circles 2-4, size 100 μm-250 μm and angle 174°-180°) and systematically investigated their motion performance under magnetic field, especially their motion bursting in mesoscopic tubes. We found that their speed increase from 0.04 mm/s to 0.08 mm/s when their circle numbers decrease from 4 to 3. Their speed continue increasing from 0.08 mm/s to 0.09 mm/s, while their circle diameter increase from 100 μm to 250 μm. Their speed will continue increase significantly from 0.08 mm/s to 0.11 mm/s when their taper angle decrease from 180° to 172°. The magnetic microhelix motors’ speed continued increase significantly from 0.11 mm/s to 0.17 mm/s, when they are in mesoscopic tubes while the tubes diameter reduced from 0.6 mm to 0.3 mm. In summary, our microhelix motors’ speed can be bursted from 0.04 mm/s to 0.17 mm/s via internal microstructure variation and external mesoscopic circumstance. We have successfully conducted vessel declogging experiments within mesoscopic tubes, and our microhelix motors are capable of declogging clot out of mesoscopic tubes. We believe that it is very promising for vessel declogging in vitro and hold great potential for declogging thrombus in vivo.