Views: 0 Author: Site Editor Publish Time: 2022-03-09 Origin: web
Super duplex stainless steel refers to the duplex steel with PREN>40, containing 25%Cr and high molybdenum (>3.5%), high nitrogen (0.22%~0.30%), the main grades are UNS S32550 (UR52N+), S32750 (SAF 2507 ) and S32760 (Zeron 100) were developed by companies such as CLI in France, SANDVIK in Sweden and MATER+PLATT in the United Kingdom. Their deformed materials came out in about 1990 and 1991 and entered the market in recent years. The composition of these three steels is similar, the difference lies in the content of tungsten and copper
Currently in China, the main grade of super duplex steel is 2507 (S32750)
2507 (UNS S32750) duplex stainless steel has strong strength and corrosion resistance, and is mainly used in chemical processing, petrochemical and subsea equipment. It has strong resistance to chloride corrosion, high thermal conductivity and low thermal expansion coefficient. The high content of chromium, molybdenum and nitrogen makes it highly resistant to pitting, crevice corrosion and general corrosion. Its impact strength is also very high, 2507 alloy is not suitable for use in a temperature environment higher than 570 ℃, and its toughness will be reduced in such an environment for a long time. Its chemical composition and mechanical properties are shown in Tables 1 and 2.
Table 1 Chemical composition (%)
Table 2. Mechanical Properties
|GRADE||heat treatment||σb (Mpa)||σs(Mpa)||δ%||硬度≤|