In　the　ultrasonic　testing　of　the　mechanical　properties　of　ferromagnetic　materials,　the　main　excitation　mechanism　modes　of　ultrasonic　waves　are　Lorentz　force　mechanism　ultrasonic　and　magnetostriction　mechanism　ultrasonic.　Lorentz　force　mechanism　ultrasonic　mainly　detects　the　conductive　characteristics　of　materials,　while　magnetostriction　mechanism　ultrasonic　mainly　detects　the　hysteresis　characteristics　of　materials.　However,　conventional　electromagnetic　acoustic　transducers　(EMATs)　cannot　simultaneously　characterise　these　two　characteristics　of　ferromagnetic　materials.　In　this　study,　we　conclude　from　the　finite　element　simulation　that　a　quantitative　lift-off　distance　(i.e.　the　distance　between　EMAT　and　the　specimen)　can　change　the　main　mechanism　mode　of　the　excited　ultrasonic　wave.　Based　on　this　conclusion,　an　electromagnet　electromagnetic　acoustic　transducer　with　dual　main　excitation　modes　(DM-E-EMAT)　is　designed,　which　can　realise　the　dual　mode　switching　of　the　main　Lorentz　force　mechanism　and　main　magnetostriction　mechanism　by　adding　or　removing　hollow　square　gasket.　The　ultrasonic　testing　of　ferromagnetic　materials　based　on　the　two　main　mechanisms　of　DM-E-EMAT　can　simultaneously　characterise　the　conductivity　and　magnetostriction　properties　of　ferromagnetic　materials,　which　enables　the　characterisations　of　two　types　of　characteristic　parameters　with　one　transducer,　improves　the　efficiency　of　electromagnetic　ultrasonic　non-destructive　testing　of　the　mechanical　properties　and　reduces　the　detection　errors　of　ferromagnetic　material.