Heat treatment technology for improving intercrystalline corrosion resistant performance of austenitic nickel-based corrosion resistant alloy

Abstract

The invention belongs to the technical field of metal material heat treatment technology and in particular relates to a heat treatment technology for improving the intercrystalline corrosion resistant performance of an austenitic nickel-based corrosion resistant alloy. The main chemical components of corrosion resistant 690 alloy according to weight percentage are as follows: 0.01-0.03 percent ofC, 28.00-31.00 percent of Cr, 8.00-11.00 percent of Fe, 58.00-63.00 percent of Ni, less than or equal to 0.05 percent of N, less than or equal to 0.50 percent of Ti, less than or equal to 0.50 percent of Al and less than or equal to 0.01 percent of S. The technology comprises the concrete steps as follows: firstly 690 alloy material is heated up to 1,050 DEG C to 1,100 DEG C to keep the temperature for 10-30 minutes and is cooled to room temperature fast; the material is heated up to 850 DEG C to 900 DEG C and treated by stabilization treatment for 2 hours and then is cooled to the room temperature fast; the material is heated up to 715 DEG C to keep the temperature for 2 to 5 hours and is cooled to the room temperature fast. The fasting cooling manner is air cooling or water cooling. Compared with the prior art, the invention has the advantages of simple operation, shortened total heat-treatable time and being capable of improving the intercrystalline corrosion resistant performance of 690 alloy obviously.

Description

technical field [0001] The invention belongs to the technical field of heat treatment processes for metal materials, in particular to a heat treatment process for improving the intergranular corrosion resistance of austenitic nickel-based corrosion-resistant 690 alloys. Background technique [0002] Alloy 690 is an austenitic nickel-based corrosion-resistant alloy, which is currently mainly used as a heat transfer tube for steam generators in pressurized water reactor nuclear power plants. The intergranular corrosion of 690 alloy is one of the most important forms of corrosion in steam generators, and its resistance to intergranular corrosion directly affects the safety and reliability of nuclear power plants. [0003] Since the solid solubility of elemental carbon in nickel-based alloys is very small, even if the alloy is fully solid-solution treated so that the carbon in the structure basically dissolves into the matrix, as the temperature decreases, the solid solubility o...

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Problems solved by technology

But obviously, on the one hand, Cr is an element that improves the corrosion resistance of alloys, and Cr 23 C 6 The Cr consumption caused by the full analysis of the form is a waste; on the other hand, the long desensitization treatment time also reduces the production efficiency of the factory and increases the production cost

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