Manganese Powder And Sintered Alloy Steels

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Machine parts are important nowadays and play a vital role in many industries. As a separate industry, the manufacture of machine parts is continually evolving – especially in the automotive industry. Powder metallurgy helps in creating better parts and overall – better systems. Manganese powder along with many other types is therefore essential to meet the demanding requirements for various parameters.

Sintered steels are usually alloyed with larger amounts of alloying elements. In some standardized sets they reach even 10% which is due to their porosity and the heterogeneity of their structure compared with conventional steels. Sintered steels are also competitive and therefore their high static and dynamic characteristics are the focus of many studies and research papers.

While copper, nickel and molybdenum are alloying elements which can and have been used from the beginning of production of sintered alloyed steels – manganese, chromium and partly silicon have not been used for preparation of sintered alloy steels. The manganese powder specifically is not a part of the sintered alloy process for manufacture of structural components.

high purity manganese metal powder

Manganese Powder And Sintered Alloyed Steels

‘Why manganese powder is not used with sintered alloyed steels?’ – you are asking yourself.

The main reason for this is the low affinity for oxygen that manganese powder has. Also, the stringent requirements on the purity of sintering atmospheres with an extremely low potential for oxide reduction covering the surface of manganese powders – despite it is one of the most affordable alloying elements.

Manganese is known for the highest affinity for oxygen and its oxides can be reduced with difficulties – only by solid carbon at very high temperature.

Although manganese is a basic element in classical metallurgy, the manganese powder is used in manufacture of extremely strong structural steels. Also, it is a powder with high wear resistance – despite its affinity for oxygen. This has been the focus on many studies which take manganese powder as an element found in the production of sintered alloy steels – one that started early in the 1950s.

The positive properties of sintered manganese steels created with manganese powder as an element clearly confirms the fact that the ‘iron powder matrix’ can use manganese powder for sintering independently, whilst not compromising the purity of the element in general.

Manganese Powder And Its Vapor Pressure

We noted that manganese has a high affinity for oxygen. Aside from that and in addition, manganese powder has a high vapor pressure. This is a physical property that cannot be controlled and is manifested by its sublimation from manganese particles in the compact.

Although it depends on the sintering temperature, manganese powder tends to weaken when being sublimated from the manganese particles. When this happens, it transforms into a form of vapor and thereby reduces the oxides covered in the surface of base plain iron or pre-alloyed powder in the compact – as well as the moisture content of the sintering atmosphere that secures the effective sintering of manganese steels.

The impact of manganese powder in the form of manganese vapor when it comes to sintering and alloying is known in the powder metallurgy literature as well as a ‘self cleaning / protection / reduction effect’ with great respect to the sintering atmosphere regardless of its purity. Manganese powder and this physical feature allows sintering of manganese steels – a common process in powder metallurgy.

A Final Word

In the end, manganese metal powder can be available in different grades. It can have a manganese oxide content that varies in different grades – from 42% to 62%. Additionally, it is widely used in the manufacturing of poultry feed, animal feed, cattle feed and manganese sulphate as a whole, not to mention its role in the fertilizer plants.