Effect of operating temperatures towards the magnetostriction of magnetorheological foams

This study used magnetorheological (MR) foam which consist of carbonyl iron particles (CIPs) that were incorporated into a polyurethane foam. The polyurethane was fabricated using two different compositions of CIPs which were 35 and 55 wt.% to investigate the magnetostriction effect with different concentrations of magnetic particles. The magnetostriction of MR foams with influence of temperatures were investigated by using shear oscillatory rheometer that equipped with the temperature’s controller applied at a specific temperature, with magnetic fields ranging from 0 to 0.7T. Based on previous research, MR foam has been found to expand in the presence and strength of magnetic fields. However, the magnetostriction of MR foams under different operating temperatures are not yet discovered since it causes changes in its behavior and performance. Therefore, the purpose of this study is to analyze the magnetostriction of MR foams at different operating temperatures between 25 to 50°C, with 5°C increment. The finding revealed that the mag-netostriction has slightly decreased at temperatures between 25 to 40°C. Nevertheless, at temperature between 40 to 50°C, the magnetostriction some-how increased for both MR foam samples. In fact, the magnetostriction for MR foam with 55 wt.% concentration of CIPs achieved higher compared to MR foam with 35 wt.% concentration of CIPs, by about 26.56% particularly at 25°C. Prior to the application of MR foam in sensors and actuators that would experience induced of heat during the operating system, it is crucial to understand the behaviors of MR foam as well as the magnetostriction under different operating temperatures.