300-series austenitic stainless steel solid solution and stabilization heat treatment process

Abstract

A 300-series austenitic stainless steel solid solution and stabilization heat treatment process comprises the following process steps of step 1, determining whether a stainless steel pipe to be processed needs solid solution or not; step 2, preparing solution heat treatment / stabilization annealing heat treatment; step 3, performing solution heat treatment, heating the steel to 1048-1200 DEG C, then performing water quenching treatment, and keeping the state to room temperature; step 4, performing metallographic examination evaluation, specifically, whether the workpiece processed in the previous step is qualified or not is confirmed; step 5, performing stabilizing annealing heat treatment, specifically, that the workpiece which is configured to be qualified is heated to 900+ / -5 DEG C as quickly as possible (in 4 hours or less), the temperature is kept for at least 4 hours, air cooling is carried out after the temperature is kept, at the moment, the carbide of Cr is completely dissolved, the carbide with titanium removed is not completely dissolved, and the carbide fully precipitates out in the cooling process, so that other carbide of carbon cannot be formed again, and therefore intergranular corrosion is effectively eliminated; step 6, taking out the workpiece; step 7, checking and trimming; and step 8, checking the quality and delivering the workpiece from a factory.

Description

technical field [0001] The invention relates to a heat treatment process for stainless steel, in particular to a heat treatment process for solid solution and stabilization of 300 series austenitic stainless steel. Background technique [0002] Stainless steel seamless pipe is a steel pipe that is resistant to weak corrosive media such as air, steam, water, and chemically corrosive media such as acid, alkali, and salt. Also known as stainless acid-resistant steel pipe. The corrosion resistance of stainless steel seamless pipes depends on the alloying elements contained in the steel. Chromium is the basic element for stainless steel to obtain corrosion resistance. When the chromium content in the steel reaches about 12%, the chromium interacts with the oxygen in the corrosive medium to form a thin oxide film (self-passivation film) on the surface of the steel. , can prevent further corrosion of the steel matrix. In addition to chromium, commonly used alloying elements for ...

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Problems solved by technology

[0003] At present, in the technology of making stainless steel seamless pipes, there are many problems that the internal stress of residual deformation is large, which leads to high-temperature recrystallization of the pipes during operation, and the tendency of intergranular stress corrosion cracks to occur due to external factors before the pipes are put into operation.

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