The high-velocity impact response of gelatin and synthetic hydrogel samples is investigated using a laser-based microballistic platform for launching and imaging supersonic micro-particles. The micro-particles are monitored during impact and penetration into the gels using a high-speed multi-frame camera that can record up to 16 images with nanosecond time resolution. The trajectories are compared with a Poncelet model for particle penetration, demonstrating good agreement between experiments and the model for impact in gelatin. The model is further validated on a synthetic hydrogel and the applicability of the results is discussed. We find the strength resistance parameter in the Poncelet model to be two orders of magnitude higher than in macroscopic experiments at comparable impact velocities. The results open prospects for testing high-rate behavior of soft materials on the microscale and for guiding the design of drug delivery methods using accelerated microparticles.

明胶和合成水凝胶样品的高速冲击响应是使用基于激光的微弹平台发射和成像超音速微粒的方法进行研究的。使用高速多帧相机在撞击和渗透到凝胶期间对微粒进行监控，该相机可以以纳秒级的时间分辨率记录多达16张图像。将轨迹与Poncelet模型的颗粒渗透率进行比较，表明实验与明胶影响模型之间具有良好的一致性。该模型在合成水凝胶上进一步验证，并讨论了结果的适用性。我们发现Poncelet模型中的强度抗力参数比在可比的冲击速度下的宏观实验要高两个数量级。