Overview

Bright annealing, commonly known as bright annealing, is mainly to heat and anneal in a confined space after slowly cooling the temperature in the confined space at least below 500 degrees, then natural cooling will have brightness and will not cause decarburization. During ordinary annealing, heating and cooling produce oxidation and decarburization. Therefore, the heat-treated steel undergoes additional processing, which increases the loss and cost of the metal, so bright annealing is often used.

ASTM A213 TP321 stainless steel tube which be processed by bright annealed, can eliminate work hardening and obtain satisfactory metallographic structure. When the performance requirements are different, the requirements for the metallographic structure after the bright annealing are different, and the process of the bright heat treatment is also different.

It can also Obtain a non-oxidizing bright surface with good corrosion resistance. Because the bright annealing is to heat the strip steel under the protective atmosphere of a mixed gas of hydrogen and nitrogen, by strictly controlling the protective atmosphere in the furnace, especially the purity, residual oxygen and dew point, a bright surface without oxidation can be obtained. Compared with the surface obtained by ordinary annealing and pickling, since there is no oxidation process, the chromium depletion phenomenon on the surface of the strip is reduced, and its corrosion resistance is better than that of the 2B plate after polishing.

Specification

ASTM A213/A213M-21a Standard Specification for Seamless Ferritic and Austenitic Alloy-Steel Boiler, Superheater, and Heat-Exchanger Tubes.

Chemical Composition

Mechanical Properties

Applications

• 1. Water Supply Systems

• 2. Power Plant

• 3. Paper & Pulp Industry

• 4. General Purpose Applications

• 5. Fabrication Industry

• 6. Food Processing Industry

• 7. Structural Pipe

• 8. Oil and Gas Pipeline

• 9. Chemical Industry

• 10. Plumbing, Heating