Annealing and solution treatment of stainless steel
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When to use annealed stainless steel and when to use solution-treated one? What’s the difference between them? Thank you!
Solution treatment: A heat treatment method for austenitic stainless steels to improve their resistance to intergranular corrosion. Heating austenitic stainless steel components (especially those that have been welded) to 1050–1100°C allows the carbides deposited at the grain boundaries (Cr23C6, Fe23C6) to dissolve back into the austenite grains. Subsequently, by rapid cooling (such as quenching of steel), the components are brought down quickly below the sensitization temperature (350–450°C) at which Cr23C6 and Fe23C6 can form, thereby preventing the precipitation of these carbides at the grain boundaries. Austenitic stainless steel after solution treatment can prevent grain-direction corrosion. Annealing: A metal heat treatment process in which the workpiece is heated to a predetermined temperature, held at that temperature for a certain period of time, and then cooled slowly. The purpose of annealing is: ① to improve or eliminate various structural defects and residual stresses caused in steel during casting, forging, rolling, and welding, thereby preventing deformation and cracking of the workpiece. ②Soften the workpiece for machining. ③Refine the grain structure to improve the microstructure and thereby enhance the mechanical properties of the workpiece. ④Prepare the microstructure for the final heat treatment (quenching and tempering). For reference only! This post was last edited by xxrewj on 2008-2-28 15:57.]
Three supply conditions: solution treatment + annealing, solution treatment, and solution treatment + quenching. There are also supply forms with solution treatment and stabilization; austenitic stainless steels do not exist in only the annealed condition. Solution treatment + annealing – for plates and bars； Solution treatment---Fasteners ； Solution treatment + quenching --- forgings,
Stainless steel generally requires solution treatment to ensure its mechanical properties and internal quality; I have not heard of any requirement for annealing. Carbon steel and low-alloy steel, on the other hand, do require annealing as a heat treatment process.
Annealing is generally not performed; instead, solution treatment or stabilization treatment is used. The type of annealing commonly applied to pressure vessels is low-temperature annealing aimed at eliminating internal stresses. This temperature range falls within the sensitization temperature range for austenitic stainless steels, making sensitization likely to occur
Solution treatment and stabilization treatment are used more often; it seems that annealed stainless steel doesn’t use them!