| As modern science and technology such as the car and aviation industries have developed rapidly, there has been moe and more demand for all kinds of special purpose materials.Complex brass as synchronizer cone ring has developed in recent years in a global range, especially in the field of automobile. High strength wear-resistant brass is a new field of the research and development in the material industry in order to adapt to the user’s requirements. Research report for cars at home and abroad with manganese brass synchronizer tooth ring is not so much, at the same time, there are also many potential problems to be explored and solved. Through discussing the changes in concentrations of Mn,Si content changes, add among different species composition of Mn, Si, adding different trace elements and electromagnetic stirring process, heat treatment process of alloy matrix organization, the second phase morphology, the second phase distribution, alloy cutting performance and wear resistance, anti dezincification corrosion, the following results are made:1. Manganese content of the alloy increases with the increase of the second phase formed in the alloy, and gathered in the grain boundary. At the same time expanded role of Si element in the beta phase is reduced. The wear-resisting performance of the alloy wear-resisting performance is worst when Mn content is3.5%, and then get better gradually along with the increase of Mn content in alloy. Dezincification corrosion performance get worse and worse. When Mn content reaches7.5%, alloy corrosion resistance to achieve the best. At the same time, the increase in Mn element shape variation of alloy, which is very good in the process of cutting chip breaker.2. The alloy increases with the increase of silicon content while the second phase precipitation amount is increasing. Also it began to gather, but it has certain refinement effect of second phase. Alloy increases with the increase of Si content, and its dezincification corrosion become worse gradually. But its cutting ability get better.3. Element mass ratio of Mn and Si (2.3-5):1is in this range, Mn and Si can be freely combined into Mn5Si3phase. Free in deviation from the range of Mn and Si first combined into Mn5Si3phase, and then combined into MnSi phase. The second phase can be done under750℃by3h after solid solution treatment. The alloy with different cooling ways to controls the second phase.4. The electromagnetic stirring technique has obvious improved the effect on the performa nce of the alloy. With the increase of electromagnetic stirring frequency, size of alloy grain is refined, homogenizd and, thus improved the alloy wear resistance.The frequen cy electromagnetic stirring under the25Hz and45Hz, the wear-resisting performance o f the alloy increased by88.2%and88.2%respectively.5. Adding Al, Al+Sn, RE, Ti+B trace elements can improve the corrosion resistance of alloy in different level, among which joined Al and under the synergy of Sn, the dezincification corrosion performance of the alloy will reaches the best. The alloy wear resistance are improved at the same time, the RE elements added to one of is the most obvious. Under the synergy of Sn and Al, the cutting performance of alloy becomes poor as a contrary. RE, Ti+B elements can be obviously improved the cutting performance of the alloy.6. High manganese brass in smelting process is easy to inhale. In front of the alloy casting, using anhydrous degasifier melt can have very good degassing effect.
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