Abstract

This project aims to develop and optimize soft magnetic materials for use in solenoids for automotive components such as: electric injectors, electric valves, electric pumps... etc. The work seeks to produce soft magnetic materials with higher magnetic permeability to produce higher magnetic forces in solenoids. Powder metallurgy was used to produce the magnetic solenoid parts with a wide array o f possible material combinations. Different mixtures o f Fe-Si, Fe-Co and Fe-Si-Co were developed. A cold-isostatic compacting technique was used with a pressure of 180 MPa. Then the samples were sintered twice at a temperature o f 1315 °C for 45 min after compacting, and after the final machining. Density, compression, hardness and microstructure were investigated for all samples before and after the second sintering. The results showed that the mechanical properties and the microstructure were improved after the second sintering. The magnetic density and intensity (B-H) was determined for each material. A sample o f each new material was sent to an American Lab. Finite element simulations were carried out using commercial software (ANSYS) to simulate the magnetic field o f a common rail electro-injector solenoid. The maximum magnetic force was determined for each developed material. Different models were built-up by varying the magnetic material properties and the working parameters such as the coil turn - current for a fixed gap between the armature and the back iron.