CRCA Steel – Cold Rolled and Close Annealed

What is CRCA Steel? CRCA is an abbreviation of “cold rolled close annealed”. This is a steel grade in which cold rolling is done after hot rolling and pickling, to reduce the thickness of steel. Cold rolling makes the material hardened. This cold rolled steel is then annealed in a close container where nitrogen or any other non-oxidizing gases softens it for use and also guards it from oxidation.

What is the application of CRCA steel: This type of steel sheet metal is mostly utilized in automobile and manufacturing industries for body and panel applications. This steel can be used in forming process and can also be utilized in a drawing process which transforms the shape of quadrilateral sheet to a beneficial 3D shape.

What is a cold rolling process and what value it adds to CRCA steel? Cold rolling process is necessary for manufacturing low thickness steel sheet below than 1.6 mm.  These low thickness cold rolled steel sheets are used in applications that need a noble surface quality whereas hot rolled steel surface has rough surface having pits and different irregularities.

Why close annealed process is applied on CRCA material? Close anneal operation relates to a annealing operation in which steel is heated to a high temperature just less than seven hundred and twenty degree Celsius. This process is performed for extended time period may be two or three days and are normally done in a bell furnace. This close annealing transforms the lamellar pearlite to spheroidal cementite and considerably develops ductility. Ductility is a fundamental requirement of steel so as to be processed through drawing process. The drawing process is also categorized as simple drawing, deep drawing, extra deep drawing and non-aging extra deep drawing quality grades. The close annealing process also improves other mechanical properties for example strain hardening coefficient and planar anisotropy.

Advantages of CRCA Steels: Some of the advantages are stated below:

  • Precise and Accurate Dimensional Tolerances
  • Robust surface finish
  • Improved mechanical & physical properties
  • Improved draw-ability

Disadvantages of CRCA Steels: Some of the disadvantages of the cold rolled close annealed steels are stated below:

  • Less Corrosion Resistant
  • Sensitive to Moisture content

Examples: Some of the examples of CRCA steel is SPCC-AS steel (commercial quality close annealed cold rolled), SPCD-AS steel (drawing quality close annealed cold rolled), SPCE-AS steel (deep drawing close annealed cold rolled), SPCG-AS steel (extra deep drawing non aging close annealed cold rolled) etc.

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