Fatigue life prediction of magneto-rheological elastomers in magnetic field

Abstract

Fatigue life is one of the most important characteristics of materials. Predicting fatigue life in magnetorheological elastomer (MRE) under combined and repetitive loads is an unavoidable step to increase the safety coefficient of MREs. In this study, high-temperature vulcanization silicon rubber (HTVSR) based MREs were fabricated by incorporating the different soft carbonyl iron particles (CIP) that samples with 10%, 20%, and 30% of CIP volume were made. Fatigue behavior of MRE under the combination of compression-tension and torsion loading in the presence and absence of magnetic fields was studied by using the multiaxial fatigue testing machine. The relationship between maximum energy density function (W max) and fatigue life (N) was achieved that it can predict fatigue life in MREs. The results showed that the dissipation energy was smaller in the presence of a magnetic field at the same CIP volume percentage and increased as the CIP volume percentages grew, because the agglomeration in the samples became more. And also with a magnetic field, at the same CIP volume percentages, the strength of the MRE increased that led to the fatigue life of MRE increasing.

The effect of repetitive magnetic and cyclic loading on the fatigue life prediction of a magnetorheological elastomer

“…Soft CI magnetic particle (d50 ¼ 6.0-7.0 mm, CS grade, supplied by BASF) is chosen in an approximate size of 6 to 7 mm because it has excellent soft magnetic properties and high saturation magnetization. The used fabrication procedure was described in a previous paper 19 for isotropic samples.…”

“…The MRE impedance properties and the storage modulus increased under magnetic fields. Hosseini et al 19 presented the relationship between maximum energy density function and fatigue life for MREs containing 0, 10, 20, and 30 vol% of CIP in the presence and absence of the magnetic field. They investigated a combination of multi-axial compression-tension and torsional forces in fixed magnetic fields for fatigue life of MREs.…”

“…In the previous work, 19 the three-dimensional model of the maximum strain energy density, which includes the stored strain energy and dissipating strain energy, was used to estimate the fatigue life. Since the dissipating strain energy section is insignificant compared to the stored strain energy section, in this paper, the dissipating strain energy section has been ignored.…”

Investigation of the performance of dopamine‐modified carbon fiber‐reinforced natural rubber‐based magneto‐rheological elastomers

“…4,5 CI particles are highly preferred as they possess several advantageous properties, including high saturation magnetization, ease of magnetization and demagnetization, and the absence of magnetic hysteresis. Hosseini et al 6 examined the impact of varying volumes of carbonyl iron particles (CIP) on the fatigue life of MREs. The findings revealed that, at the same volume percentage of CIP, the dissipated energy was reduced in the presence of a magnetic field.…”

Magnetorheological response of Permalloy@ styrene‐b‐(ethylene‐co‐butylene)‐b‐styrene elastomers as a function of filler concentration

“…The use of these elastomers is always defined by their characteristic physicochemical properties, including high elasticity, flexibility, chemical resistance, and impact resistance, which are essential for many applications. On the other hand, typical examples of magnetic fillers include carbonyl iron (CI), 11,12,14,16 Fe, 17 CoFe 2 O 4 , 18 Ni, 19 Co, 13 and FeCo 3 20 particles. These active fillers based on soft or hard particles with nano‐ or micrometer‐sized must be carefully selected to obtain an adequate combination of MRE properties.…”