X2CrNiMoCuWN25-7-4 

HuaNickel X2CrNiMoCuWN25-7-4 is a super austenitic stainless steel known for its superior resistance to chloride pitting and crevice corrosion. This stainless steel performs well in a variety of corrosive environments, especially seawater and other chlorine-containing media, making it widely used in marine engineering, chemical equipment, food processing, and more.

X2CrNiMoCuWN25-7-4 Chemical composition：

	Ni	Mo	Cr	N	C	Si	Mn	Cu	S	P
Min	23.5	6	20	0.18	–	≤
Max	25.5	7	22	0.25	0.03	0.1	2	0.75	0.03	0.04

X2CrNiMoCuWN25-7-4 Physical properties：

Density/g·cm-3	Coefficient of thermal expansion/℃×10-6		Specific heat capacity/J·(kg·K)-1	Magnetic permeability/Oe(Oerst)	Young’s modulus of elasticity/GPa
8.06	100℃	500℃	461	1.003	195
	15.3	17.2

X2CrNiMoCuWN25-7-4 Mechanical properties：

σb/MPa	σp0.2/MPa	δ/%	Hardness  ( H R B )
≥690	≥310	≥30	<240

X2CrNiMoCuWN25-7-4 Alloy properties：

The solid solution state of super austenitic stainless steel of this composition has a single austenite, and there is no intermetallic phase, but if it is ≥ to 540 °C, there will be carbon, nitride and σ phase precipitation, for which the amount of chromium and molybdenum is at the upper limit of chemical composition will be more sensitive.

X2CrNiMoCuWN25-7-4 Uses of alloys：

thin-walled tubes for seawater condensers; At the same time, it can also be used for important equipment and pipelines resistant to chloride local corrosion in paper and thermal power plants, FGD and offshore oil production platforms.

X2CrNiMoCuWN25-7-4 Process performance：

Welding process: HuaNickel X2CrNiMoCuWN25-7-4 has good welding performance, and can be welded by the general process method of austenitic stainless steel. Since this steel is mostly used as a tube for heat exchangers, automatic welding or manual welding is recommended for the welding of pipes and tube sheets.

Heat treatment:HuaNickel X2CrNiMoCuWN25-7-4 composition upper and lower limit test, short-term heating at 1065 °C can make the σ in X2CrNiMoCuWN25-7-4 steel containing 22% Cr, 7% Mo soluble in the matrix. The solution treatment temperature of this steel is 1065~1105 °C.

Relevant standards：

ASTM B 564-2004