Method for manufacturing austenite series heat-resistant alloy pipe and austenite series heat-resistant alloy pipe manufactured by the method

Abstract

The invention provides a method for manufacturing an austenite series heat-resistant alloy pipe and an austenite series heat-resistant alloy pipe manufactured by the method, the austenite series heat-resistant alloy pipe is excellent in creep strength of hot working / cold working position after heat treatment. The method for manufacturing the austenite series heat-resistant alloy pipe comprises bending, expanding, hot working or cold working an alloy pipe after heat treatment to form a working portion, and after baking with the condition that the rate of coverage of carbonized matter in grain boundaries of the metallographic structure of the working portion and an intermetallic compound is below 50%, wherein the alloy pipe comprises chemical composition as following, by mass, 0.02 % to 0.13 % of C, less than 1 % of Si, less than 2 % of Mn, less than 0.03 % of P, less than 0.01 % of S, 25 % to 36 % of Cr, 40 % to 60 % of Ni, less than 0.3 % of Al, 2.0 % to 10.0 % of W, 0.05 % to 1.5 % of Ti, 0.002 % to 0.03 % of Zr, 0 % to 3 % of Mo, 0 % to 1.5 % of Nb, 0 % to 15 % of Co, 0 % to 0.05 % of Ca, 0 % to 0.05 % of Mg, 0 % to 0.2 % of rare earth element, 0 % to 0.2 % of Hf, 0 % to 0.2 % of B, 0 % to 1.5 % of V, 0 % to 2.0 % of Ta, 0 % to 3.0 % of Re, and the reminder comprising Fe and inevitable impurities.

Description

technical field [0001] The present invention relates to a manufacturing method of an austenitic heat-resistant alloy pipe and an austenitic heat-resistant alloy pipe manufactured by the manufacturing method. Specifically, the present invention relates to a method for producing an austenitic heat-resistant alloy pipe used as a pipe material in a boiler for power generation, equipment for chemical industry, and the like, and an austenitic heat-resistant alloy pipe produced by the production method. Background technique [0002] Today, coal-fired power generation occupies a very important position in the domestic power supply. Unlike oil and other energy sources, coal is produced on average in the world and its price is relatively stable, so it is expected to be widely used as a basic energy source in the world in the future. However, the CO per unit of electricity produced by coal-fired power 2 The amount of gas discharge is larger than that of other power generation systems...

AI Technical Summary

Problems solved by technology

Therefore, the high-temperature strength of common austenitic heat-resistant alloys such as SUS304H, SUS316H, and SUS347H is insufficient especially in superheater tubes where the temperature becomes high.

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