Hot-rolled steel coil pickling, cold rolling and annealing process, become a cold-rolled steel coil.
Through the process of multi-channel, many of the cold-rolled steel quality characteristics can be controlled.
Compared with hot rolled coils, cold rolled product has the following advantages:

1. The surface roughness can be controlled, the roughness Code20/25/35 ingredient production. If more than strictly by rolling control, roughness can be further decline after plating higher surface gloss.

2. Hardness adjustable
3. More uniform tissue hardness variation is small, the entire volume coil
for the same type of organization, its hardness variation within the volume is smaller.
4.Ball of material ductility ball of material can reduce mold wear, extend die life, suitable for more stringent form processing.

5. Produce thinner
6. Higher accuracy of the dimensions (thickness, width, edge drop)

(Hardness Average In Hot Rolled Stage)

HRB
	HRC	PA-S	ASCR	CR
(R)	7	9	2	3
(MIN)	91	78	102	78
(MAX)	98	87	104	81
(AVG)	93.6	82.6	103.6	79.6
(STD)	2.1	3.2	0.6	0.7

(Hardness range according to different type of carbon steel )
 
S35CM: 80max、85max、85-95、95-105
S45CM: 80max、85max、85-95、97-105
S50CM: 82max(R35)、85max、80~90、85~95、97~105
A684-1060: 85max
ASTMA684-1065: 85max、87max、85-95、97-105
ASTM684-1070: 90max、98~108
SK85M: 90max、85-95