Effects of the Mn and Zr elements on microstructure

mechanical properties and wearing resistance of Ti based TMA alloy（Ti-11.3Mo-6Zr-4.3Sn）for orthodontics were investigated by optical microscope（OM）

XRD（X-ray diffraction）

digital micro-hardness tester

abrasive testing machine

SEM（scanning electron microscope）.The results reveal that substitution of element Mn for Mo can not change phase constituent in TMA alloy

however

a little of α’’ phase can be observed after quenching treatment.ω phase can be created in as-cast microstructure of the TMA alloy with increasing in Zr content

which is transformed into β phase after quenching.Hardness of the TMA alloy is increased and elastic modulus is decreased

and wearing mechanism of the TMA alloy is characterized by abrasive wear and coherent wear

and abrasive wear behavior is improved and coherent wear is deteriorated with substitution of Mn for Mo and the increase of Zr content.