Nickel base alloy and rustless steel valve possessing nickel base alloy layer seal surface and its preparation method

Abstract

The invention relates to a nickel-based alloy, a stainless steel valve provided with a seal surface of a nickel-based alloy layer and a preparation method. The components and the contents of the nickel-based alloy used on the seal surface of the nickel-based alloy layer are respectively: 1.0 to 1.5wt percent of C, 17.5 to 19.5wt percent of Cr 7.0 to 9.0wt percent of Mo, 3.5 to 4.5wt percent of W, 1.5 to 2.5wt percent of Nb, 2.0 to 3.0wt percent of Si and the rest is Ni. The stainless steel valve provided with a seal surface of a nickel-based alloy layer is lead the powder of the nickel-based alloy to form a seal surface nickel-based alloy on the stainless steel valve through a laser plating method. The nickel-based alloy layer and a stainless steel matrix are completely metallurgically bonded without the defects like cracks, air holes, and the like. The alloy layer comprises nickel-based solid solution dendrites, the metallic carbides between the dendrites, the metal silicides, and the like. The reinforced layer of the nickel-based alloy has higher rigidity (HRC43-49) and excellent properties for anti-heat and shock and can be used for preparation the alloy reinforced layer on the seal surface of the stainless steel which has strict demands on the alloy components (B and Co are excluded).

Description

technical field [0001] The invention relates to a nickel-based alloy, a stainless steel valve with a nickel-based alloy layer sealing surface and a preparation method thereof, belonging to the field of surface modification of metal materials. Background technique [0002] Due to its excellent corrosion resistance and mechanical properties, stainless steel is widely used in the manufacture of various acid-resistant valves and high-temperature and high-pressure valves in petrochemical, reactor and nuclear power plants. Since various media are highly corrosive or even radioactive during operation, and the sealing surface of the valve is frequently subjected to friction, extrusion and impact during the opening and closing process, the sealing surface of the valve is easily damaged, which greatly shortens the life of the valve. The service life, and the leakage of the medium may cause stoppage of work and production, environmental pollution and even serious accidents. Therefore,...

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Problems solved by technology

The powder presetting method is generally only suitable for cladding a layer of material on the surface of the material. The thickness of the cladding layer is limited. If the powder is too thick, it is difficult to ensure the metallurgical bonding between the coating and the substrate and good coating performance during cladding. ; The powder preset method cannot guarantee the continuity of the cladding process when the thicker alloy layer is prepared by multi-layer cladding, and the process is more cumbersome; it is found through experiments that when the laser cladding Tribaloy T-700 alloy, due to the alloy layer The toughness is poor, and the cladding layer is very easy to crack; in addition, Tribaloy T-700 alloy and the above-mentioned cobalt-based and nickel-based alloys contain Co or B, which cannot meet the requirements of some nuclear industry valve sealing surfaces. The strengthening layer cannot contain B and Co. strict requirements

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