Improved magnetostriction of Tb-doped Ni45Co10Mn20Ga25 ferromagnetic strain glass

Abstract

Highly sensitive magnetostrictive materials with low-field-triggered large magnetostriction are crucial for miniaturized actuator and sensor applications but have rarely been achieved. Accumulated experimental results indicate that ferromagnetic strain glass with nano-sized domains can lead to a low magnetic field required to achieve saturation magnetostriction but cannot guarantee large magnetostriction. Therefore, finding effective ways to enhance their magnetostriction is essential for achieving highly sensitive magnetostrictive effects. In this work, we investigated the impact of Tb-doping on the transformation behavior and magnetostrictive property of Ni₄₅Co₁₀Mn₂₀Ga₂₅ ferromagnetic strain glass bulk samples. We found that the martensitic transformation start temperature gradually increases with rising Tb doping levels. The comparative results reveal that trace amounts of Tb-doping significantly enhance the magnetostriction of Ni₄₅Co₁₀Mn₂₀Ga₂₅. Further investigation revealed that trace Tb-doping leads to a relatively high volume fraction of nano-domains at room temperature, resulting in a larger magnetostriction.