What are CR4 Steels? CR4 steels are deep drawing quality Aluminum Killed (non-aging) mild steel revealed in ISO 3574 and are graded correspondent to SPCF steels in JIS G3141 standard. The only difference between CR3 & CR4 steels is that CR4 steels are non-aging steel and are very slowly deteriorated in mechanical properties with respect to time.
Dimensional Range of CR4 Steel: CR4 Steels is available from thickness series 0.25 mm to 4.0 mm. The width is typically 950 mm, 1219 mm, 1500 mm and 2000 mm.
Chemical Composition of CR4 Steel: The chemical composition of CR4 Steels is contained by 0.08 percent of Carbon maximum, 0.40 percent of manganese maximum, 0.030 percent of Sulphur maximum, 0.02 percent of Phosphorous maximum, and remaining percentage is of iron (Fe) with negligible impurities.
Mechanical Properties of CR4 Steel: The mechanical properties of CR4 Steels are related to SPCF steels, but contrasting the JIS G3141 standard, the ISO 3574 standard does not categorize the minimum tensile strength but it determines the maximum range. The maximum yield strength is 210 MPa, the utmost tensile strength is 350 MPa and least elongation is 38 percent. The hardness is 50 HRB maximum.
As compare to CR3 Steel, this grade of steel is additionally draw-able & adequate for extra deep drawing operations.