Cold-rolled steel sheet for enamel and preparation method of cold-rolled steel sheet

The invention particularly relates to a cold-rolled steel sheet for enamel and a preparation method of the cold-rolled steel sheet, and belongs to the technical field of steel preparation. The cold-rolled steel sheet is prepared from the following chemical compositions in percentage by mass: less than or equal to 0.0040% of C, less than or equal to 0.01% of Si, 0.1%-0.5% of Mn, less than or equalto 0.015% of P, less than or equal to 0.0050% of S, less than or equal to 0.01% of Alt, less than or equal to 0.0050% of N, 0.01%-0.05% of O and the balance of Fe and inventible impurities. The cold-rolled steel sheet for the enamel has high strength and high elongation, yield strength is greater than 200MPa, percentage elongation after fracture A50mm is greater than 40%, formability is good during corrugation pressing, a heat transfer element of a heat exchanger using the cold-rolled steel sheet as a raw material is not prone to cracking under the high-pressure water washing environment, andthe heat exchanger has a l