Magnetostrictive materials are usually used in sensor technology since they are sensitive to magnetization and strain. Unfortunately, to date, only a few magnetostrictive materials are being used, as the need for a strong magnetic field (1 T) and not sensitive at a low magnetic field. Thus, in this study, a new magneto-active (MA) polyurethane foam was fabricated to obtain a strain at a low magnetic field corresponding to below 1 T. The in-situ fabrication of the MA foam was carried out with various compositions of carbonyl iron particles (CIPs), particularly at 35, 45, 55, 65 and 75 wt%. An analysis of the magnetic properties revealed that all the MA foams showed high magnetic saturation with low remanence values. Furthermore, the MA foam of 75 wt% showed the highest magnetostrictive strain of 1.66% at 0.45 T. The sensitivity of the MA foam is 0.0146%/mT with 42% of improvement. Analyses show MA foam of 75 wt% had a low density, biggest pores and long struts that might have led to high flexibility for elongation to produce a high strain percentage within the practical magnetic field range. Hence, this MA foam can be further utilized for sensor applications.

磁致伸缩材料通常用于传感器技术，因为它们对磁化和应变敏感。不幸的是，迄今为止，由于对强磁场（1T）的需求并且在低磁场下不敏感，因此仅使用了几种磁致伸缩材料。因此，在这项研究中，制造了一种新的磁活性（MA）聚氨酯泡沫塑料，以获得在低于1 T的低磁场下的应变。MA泡沫塑料的原位制造是使用各种羰基组成进行的铁颗粒（CIP），尤其是35、45、55、65和75 wt％。磁性的分析表明，所有的MA泡沫材料都显示出高的磁饱和度和低的剩磁值。此外，75％（重量）的MA泡沫在0.45 T时显示出最高的磁致伸缩应变1.66％。MA泡沫的灵敏度为0。0146％/ mT，有42％的改善。分析表明，重量百分比为75％的MA泡沫具有低密度，最大的孔隙和较长的支杆，这可能导致伸长率具有较高的柔韧性，从而在实际磁场范围内产生较高的应变百分比。因此，该MA泡沫可进一步用于传感器应用。