Chemical Composition:
Grade
Chemical composition % (maximum unless stated)
C
Si
Mn
P
S
Cr
Mo
Ni
A4
0.08
1.0
2.0
0.05
0.03
16.0 to 18.5
2.0 to 3.0
10.0 to 14.0
Mechanical properties :
Property Class
Diameter Range
Bolts, screws & studs
Nut
Tensile strength N/mm²(min)
0.2% Proof stress N/mm²(min)
Extension (min)
Proof Load stress N/mm²(min)
A4-50
up to M39
500
210
0.6d
500
A4-70
up to M20
700
450
0.4d
700
A4-80
up to M20
800
600
0.3d
800
BS6105 Corrosion-resistant stainless steel fasteners
1