What are the surface quality inspection standards for cold-rolled steel sheets?
No obvious scratches, pitting, oxide scale, or rust; uniform color difference; conforming to the corresponding material surface grade (e.g., FB, FC).
What are the dimensional inspection items for cold-rolled steel sheets?
Thickness, width, length, diagonal deviation, flatness, etc.
How are the mechanical properties of cold-rolled steel sheets tested?
Yield strength, tensile strength, and elongation are measured through tensile tests; HRB or HV hardness is measured through hardness tests.
What is the purpose of the bending test for cold-rolled steel sheets?
To test the plasticity and toughness of the sheet material to prevent cracking during processing.
What causes "wavy edges" in cold-rolled steel sheets?
Uneven pressure during rolling and inconsistent annealing temperatures constitute a sheet shape defect that affects subsequent processing.