Martensite refractory stainless steel and manufacturing method thereof

Abstract

The invention provides a martensite refractory stainless steel and a manufacturing method thereof. The martensite refractory stainless steel comprises the following chemical compositions by weight percentage: 0.10 to 0.20 weight percent of C, less than or equal to 0.50 weight percent of Mn, less than or equal to 0.50 weight percent of Si, less than or equal to 0.030 weight percent of P, less than or equal to 0.015 weight percent of S, 10.00 to 13.00 weight percent of Cr, 1.50 to 2.50 weight percent of Ni, 0.60 to 1.00 weight percent of W, 1.30 to 1.70 weight percent of Mo, 0.15 to 0.30 weight percent of V, 0.20 to 0.40 weight percent of Nb, 0.02 to 0.12 weight percent of N, and the balance of Fe and inevitable impurities. A martensite stainless steel with strength and toughness matching, strong heat tolerance and corrosion resistance is manufactured by intensified vacuum smelting and forging technology. The martensite refractory stainless steel can work for a long time at high temperature of 650 DEG C, and can satisfy the using requirement of heat resistant critical components applied to steam turbines and combustion turbines.

Description

technical field [0001] The invention relates to heat-resistant stainless steel materials, in particular, the invention relates to a martensitic heat-strength stainless steel and a manufacturing method thereof. Background technique [0002] Heat-resistant steel refers to steel that has sufficient strength at high temperatures, certain oxidation and corrosion resistance, and long-term structural stability. The development of heat-resistant steel is the need for power machinery working at high temperatures, such as steam boilers and steam turbines in thermal power plants, jet engines in the aviation industry, and high-temperature working parts in industrial sectors such as aerospace, ships, petroleum and chemical industries. They are subjected to various loads at high temperatures, such as stretching, bending, torsion, fatigue and impact, etc. In addition, they are also in contact with high temperature, steam, air or gas, and high-temperature oxidation or gas corrosion occurs o...

AI Technical Summary

Problems solved by technology

[0004] At present, there are certain problems in the composition design, quality level and production technology of heat-resistant materials for steam turbines, gas turbines and various engines (such as pressure-resistant and high-temperature resistant shells, discs, blades, shafts, fasteners, etc.) : 1) There are defects in the composition design of steel grades. For example, no or a small amount of strengthening element nitrogen is added to this kind of steel grades, resulting in insufficient heat resistance of the steel.

2) The production process is not standardized. For example, if the double vacuum smelting process is adopted, the overall chemical composition needs to be controlled, which increases the cost but does not improve the performance and quality of the steel, resulting in low economic competitiveness in the steel market

Steel grade 1Cr10Co6NiMoNbN and steel grade 1Cr10Co3W2MoVNbN are respectively added a large amount of precious metals Co and W elements. Although Co can improve the creep strength of steel, it increases the production cost.

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