Development of magneto-rheological fluid composites with rigidification characteristics

Magnetic and magneto-rheological materials have been widely used in many engineering applications. The smart magnetic materials addressed in this study consist of magnetically activated composites made from a core layer of a carrier-material-like fabric, sponge and silicone in combination with small magnetizable ferrous particles suspended in a magneto-rheological fluid. Composite materials that contain magnetic and magneto-rheological ingredients are presently becoming very popular in shape and structure control solutions in a variety of engineering applications. The magneto-rheological response in smart materials allows for the real-time adaptation of material properties. Adequately designed magneto-rheological or magnetic composites are required to perform under different load conditions and provide some rigidification in a sample or a structure. Three different composites are developed in this study including: magneto-rheological fabric composites (MR/FC), magnetic elastomers (M-elastomers) and magneto-rheological sponge composites (MR/SC). The experimental set-up, including custom-made hardware, software and data acquisition system, is designed to conduct experiments used to quantify the material response in shear, tension and compression. The experimental results show a close correlation between the amount of magneto-rheological material present in the specimen and the final displacements in the samples. The resistance to the shear, compressive or tensile forces increases in the samples with the higher concentration of ferrous particles when subjected to a magnetic field. An increased intensity of the magnetic field allows for a stronger magneto-rheological effect and more stable formation of the ferrous chains inside the composites.