Cold heading quality steel wire rods
Medium carbon steels with boron contents of 8 to 50 ppm are utilized in cold heading process to manufacture miscellaneous types of bolts and nuts. Adding boron in steels can improve hardenability and cold formability simultaneously during manufacturing process of bolts. Two common grades of this group of steel are 10B21 and 10B38 wire rods which are manufactured according to the requirements of ASTM F2282 standard. Chemical and mechanical properties of these grades are indicated in the tables below.
Products Specification:
Grade
10B21
Standard
ASTM F2282
Type of product
wire rod
Microstructure
ferrite+pearlite
Production process
Hot rolling
Mechanical properties:
Tensile test standard
ISO 6892-1
Tensile strength(MPa)
480-550
Yield strength(MPa)
310-350
Reduction of area R.A(%)
65-70
Elongattion
35-45
Chemical Analysis:
Alloy
Min.
Max.
C
0.19
0.23
Si
-
0.12
Mn
0.8
1.1
P
-
0.02
S
-
0.02
Cr
-
0.1
Mo
-
0.01
B
8ppm
50ppm
Cu
-
0.1
Al
-
0.005
Available sizes(mm)
5.5,6.5,8,10,12,14
Max. of ovality
0.2mm