Chemical composition analysis of 310S high temperature resistant stainless steel material

310S heat-resistant stainless steel, as an important metal raw material used in the aerospace and chemical industries, is widely used in high-temperature environments. High-temperature oxidation is also a key type of corrosion damage at high temperatures, so the development of new stainless steel materials that can resist high-temperature oxidation is of far-reaching significance for improving national defense. Among them, austenitic heat-resistant stainless steel 310S is a high-chromium nickel austenitic stainless steel.
The role of nickel in stainless steel is that nickel must be combined with chromium to play its real role. First of all, nickel is a good corrosion-resistant element and is also an important alloying element in stainless steel. Nickel is an important element in stainless steel to generate austenite. However, if low-carbon nickel stainless steel wants to obtain an austenite structure, the nickel content needs to be as high as 24%; and only when the nickel content reaches 27% can the corresponding properties of stainless steel materials be significantly changed. Corrosion resistance in media. So nickel material alone cannot form stainless steel. Only when nickel and chromium are present in the stainless steel composition, nickel-containing stainless steel will have many better properties.
It is through the above circumstances that the role of nickel in stainless steel can change the metallographic structure of high-chromium stainless steel in order to improve its corrosion resistance and process performance.
Secondly, manganese and nitrogen elements can also replace the nickel element in chromium-nickel stainless steel. Although chromium-nickel austenitic stainless steel has many advantages, the large-scale use and development of nickel-based heat-resistant alloys and heat-strength steels containing less than 20% nickel has led to an increasing demand for nickel ore resources, but nickel The total amount of mineral reserves is low and the distribution is sparse, so there is a contradiction between the supply and demand of nickel on a global scale. Therefore, in countries and regions with less nickel resources, a large number of scientific research and production practices have been carried out to save nickel and replace nickel with other elements. In this regard, the most researched and applied methods are to use manganese and nitrogen to replace stainless steel and resistant materials. Nickel in hot steel.
Among them, manganese has the same effect on austenitic stainless steel as nickel. But to be more precise, the role of manganese is not to generate austenite, but to reduce the critical quenching speed of stainless steel, improve the stability of austenite during cooling, and control the decomposition of the austenite structure, so that It can keep the austenite structure generated at high temperature to normal temperature.
In terms of enhancing the corrosion resistance of stainless steel, manganese does not play a big role. For example, if the manganese content in stainless steel changes from 0 to 10.4%, it will not optimize the corrosion resistance of stainless steel materials in air and acid. This is because manganese has little effect on increasing the electrode potential of iron-based solid solutions, and the protective ability of the oxide film generated is also very small. Therefore, although there are austenitic steels alloyed with manganese in the industry, they cannot be used as stainless steel. .