A magnetostrictive system in electronic devices converts vibrations into electrical energy through a phenomenon called the magnetostrictive effect. Magnetostriction is the property of certain materials to change their shape when subjected to a magnetic field. This effect is reversible, meaning that the material changes its shape when a magnetic field is applied and also generates a magnetic field when mechanically deformed.
Here's how a magnetostrictive system works to convert vibrations into electrical energy:
Material Selection: The core of the magnetostrictive system is typically made from a magnetostrictive material, which exhibits the magnetostrictive effect. Commonly used materials include nickel, iron, and various alloys.
Mechanical Vibrations: When mechanical vibrations or stress are applied to the magnetostrictive material, it experiences a change in its physical dimensions. These vibrations can be in the form of sound waves, pressure waves, or any other mechanical disturbance.
Magnetostrictive Effect: The mechanical vibrations cause the material to change its shape slightly. This deformation results in a strain within the material.
Magnetic Field Generation: The strain within the material leads to a change in its magnetic properties. This change in magnetization generates a magnetic field around the material.
Electromagnetic Induction: The changing magnetic field induces an electromotive force (EMF) or voltage across a nearby coil or winding of wire. This phenomenon is known as electromagnetic induction and is the same principle used in transformers and generators.
Electricity Generation: The induced voltage across the coil or winding can be harvested as electrical energy. This voltage can then be used to power electronic devices or be stored in batteries.
It's important to note that while the magnetostrictive effect can convert mechanical vibrations into electrical energy, the efficiency of this conversion process can vary depending on factors like the material used, the design of the magnetostrictive system, and the amplitude and frequency of the vibrations. Additionally, the amount of electrical energy generated might be relatively small compared to other energy harvesting methods. Magnetostrictive systems are often used in specialized applications where there are specific requirements for converting mechanical vibrations into electricity.