应用于微重力流变实验的旋转流变仪

Rotational Rheometer Used for Microgravity Rheology Experiments

基于失重条件下的流变学实验需求，针对国内流变学空间实验仪器的空白，研制适用于航天发射和微重力实验的旋转流变仪．以五相步进电机驱动旋转，采用应变式扭矩传感器，并增加预紧轴承提高旋转精度，通过滑台驱动和光栅尺定位反馈完成液位厚度调整和拉伸运动．剪切转速区间0．01～1000r／min，平均转速精度优于1％，实现了150mm／s的高速拉伸和0．5μm精度的样液厚度调整．通过测量标准硅油取得地面实验数据，得出该方案可行的结论，相对于商用流变仪，采用该方案的流变仪可进行长行程拉伸流变测量，且结构坚固可靠、体积小、重量轻，可实现发射入轨且成本低廉．

To meet the demand of theology experiments in zero-gravity condition and to fill the blank of space rheology instruments in China, a rotational rheometer, suitable for space launching and mierogravi- ty experiments, is designed. The rheometer used a five-phase step motor to drive the rotation and a strain gauge based torque sensor for measurement. Pre-tightening force was added on the bearing to improve the precision of spinning. By driving on a linear guide rail and the location feedback of a grating, it can ad- just the sample thickness precisely while making fast stretches. The rotating rate ranges from 0.01 r/min to 1 000 r/min within the accuracy of 1%. The stretching speed reaches 150 mm/s. The thickness ad- justment has 0. 5 μm accuracy. A group of silicone oil samples was measured on the rheometer to test its function. And the conclusion is that this plan is feasible. Rheometer of this structure can achieve longer extensional rheology measurement. And it is sturdier, smaller and lighter than commercial purpose rhe- ometers, making its launching mission feasible and cheap.