基于交变磁场红外热像的磁性水凝胶缺陷检测

Magnetic hydrogel, a hydrogel with magnetic nanoparticles and unique magnetic response characteristics, has been widely used in fields of tissue engineering scaffolds, bioengineered cell separation, drug carriers, and environmental engineering. The distribution of magnetic nanoparticles in magnetic hydrogels plays a decisive role in their magnetic responses, which makes the analysis of the magnetic homogeneity of magnetic hydrogels a necessity. Yet there still lacks sufficient research or practice in non-destructive testing of magnetic hydrogels and has not been reported in the literature. Based on the backgrounds above, a novel non-destructive testing method for magnetic hydrogel defect detection has been developed, that is, the infrared thermal imaging method based on alternating magnetic field. The specific work is as follows. The magnetic hydrogel and copper powder silica gel plate have been detected, and furthermore, the feasibility of the principle of the magnetic hydrogel's getting heated has been verified under the alternating magnetic field. through the detection of magnetic hydrogels with different concentrations, the feasibility of using alternating magnetic fields infrared for The uniformity analysis of magnetic nanoparticles in magnetic hydrogels is verified. The uneven distribution of magnetic particles and bubble defect have also been detected and it has been found that the method works in the above detections. Based on theoretical analysis, it is deduced that there could be a linear relationship between the surface temperature rise rate of the magnetic hydrogel and the concentration of the magnetic nanoparticles under the alternating magnetic field. Through fitting the measured data of different concentration hydrogel, the above deduction is further proved.