[en] In the last decades, many anti-vibration applications have been developed to increase the life time of components, the comfort and the security. Most of these applications are based on materials that cannot be adapted to variable working conditions, so that smart materials arise as an alternative. Within these group of materials, magnetorheological elastomers are found whose dynamic properties can be reversibly modified and controlled by an external magnetic field. The main goal of the presented dissertation was to analyse the magneto-thermodynamic behaviour of magnetorheological elastomers to enhance its use in industrial applications. Isotropic and anisotropic magnetorheological elastomers samples were synthesised with three different matrices and eight particle contents to study the shear magneto-viscoelastic properties. A new criteria analysing the loss factor and storage modulus was determined to define the shear linear viscoelastic region of magnetorheological elastomers, and the influence of synthesis and characterisation variables in the linear region was studied. Within this linear region, the magneto-viscoelastic properties of isotropic and anisotropic magnetorheological elastomers were studied, and the maximum attenuation variability of these materials was established. A new magneto-dynamic compression test was designed and manufactured, and the procedure to characterise magnetorheological elastomers at high frequencies in compression mode was implemented. Furthermore, the linear viscoelastic region was defined in these working mode, and the magneto-dynamic properties were analysed as a function of the particle content, the frequency and the magnetic field. Finally, two new magneto-viscoelastic models were developed, one for isotropic and another one for anisotropic magnetorheological elastomers. In both models, the viscoelastic nature was modelled using a four-parameter fractional derivative model, and the influence of temperature was introduced using the Arrhenius model. Moreover, the influence of particle content in each parameter was analysed and modelled, and a new magneto-induced modulus model based on the dipole-dipole interactions was coupled with the developed models for isotropic magnetorheological elastomers. In respect of anisotropic magnetorheological elastomers, a new magnetoinduced modulus model was developed using magnetic permeability components, and it was coupled to the viscoelastic effect in a single magneto-viscoelastic model for anisotropic magnetorheological elastomers.

[eu] Azken hamarkadetan, bibrazioen aurkako aplikazioen helburu nagusia osagaien bizitza erabilgarria, erosotasuna eta segurtasuna areagotzea izan da. Hala ere, gaur egungo aplikazioek lan-baldintza aldakorretara moldatzeko malgutasuna behar dute. Hori dela eta, material adimenduak gero eta gehiago erabiltzen ari dira industriako sektore ezberdinetan. Material talde honen barruan elastomero magnetoerreologikoak daude, eremu magnetiko baten eraginpean beraien propietateak aldatzen dituztelako. Tesi doktoral honen helburu nagusia elastomero magnetoerreologikoen propietate magnetotermiko biskoelastikoak aztertzea da, aplikazio industrialetan elastomero magnetoerreologikoen erabilpena areagotu ahal izateko. Hiru matrize ezberdin eta zortzi partikula-kontzentrazio bolumetriko erabili dira elastomero magnetoerreologiko isotropo eta anisotropoak sintetizatzean. Galerafaktorea eta metatze-modulua aztertzen dituen irizpide berria proposatu da sintetizaturiko laginen tarte biskoelastiko lineala definitzeko. Gainera, tarte honen sintesieta karakterizazio-aldagaiekiko menpekotasuna aztertu da. Tarte biskoelastiko lineala definitu ostean, sintesi- eta karakterizazio-aldagaien eragina propietate magnetobiskoelastiko linealetan aztertu dira. Horrela, material hauen atenuazio maximoaren aldakuntza definitu da. Bestalde, konpresio-entsegu magnetodinamiko berria diseinatu eta fabrikatu da, elastomero magnetoerreologikoak frekuentzia altuetan neurtu ahal izateko. Konpresioko propietateak neurtzeko prozedura definitu eta gero, elastomero magnetoerreologiko isotropoen konpresio-tarte biskoelastiko lineala aztertu da. Horrela, partikulakontzentrazioaren, frekuentziaren eta eremu magnetikoaren eragina propietate magnetobiskoelastiko linealetan definitu da. Azkenik, bi modelo magneto-biskoelastiko berri garatu dira, bata elastomero magnetoerreologiko isotropoetarako eta bestea anisotropoetarako. Bi ereduetan, bilakaera biskoelastikoa aurreikusteko lau parametroko deribatu frakzionarioen eredua erabili da. Arrhenius-en eredua erabiliz tenperaturearen eragina modelatu da, eta proposaturiko eredu biskoelastikoari gehitu zaio. Gainera, proposaturiko ereduko parametro bakoitzean partikula-kontzentrazioak duen eragina aztertu eta modelatu da. Elastomero magnetoerreologiko isotropoetan eremu magnetikoak eragiten duen modulu magneto induzitua modelatzeko, dipolo-dipolo interakzioetan oinarritua dagoen eredua garatu da. Elastomero magnetoerreologiko anisotropoei dagokienez, eremu magnetikoarekiko menpekotasuna modelatzeko material hauen permeabilitate magnetikoetan oinarritua dagoen eredua garatu da. Eredu biskoelastikoa eta eredu magnetikoa elkartuz, elastomero magnetoerreologiko anisotropoen bilakaera magnetobiskoelastikoa aurreikusten duen eredu berri bakar bat garatu da.