Techno Bolts Industries
ISO Certificate

Technical Information

MECHANICAL PROPERTIES FOR BOLTS, SCREWS AND STUDS — AUSTENITIC STEEL GRADES ISO 3506-1:2009 (EXTERNALLY THREADED FASTENERS)

Group Grade Property Class Size range Min. Tensile Strength MPA Stress at 0,2 % permanent strain min MPA Elongation after fracture min Grade Identification Marking
Austenitic A2 70 M6-M42 700 450 0.4d
Austenitic A2 80 M6-M42 800 600 0.3d
Austenitic A4 70 M6-M42 700 450 0.4d
Austenitic A4 80 M6-M42 800 600 0.3d

MECHANICAL PROPERTIES PER ISO 898-1 (EXTERNALLY THREADED FASTENERS)

Group Material Size Range Min. Proof Strength MPA Min. Tensile Strength MPA Core Hardness Rockwell
Min. Max.
Min. Yield Strength MPA Grade Identification Marking
4.6 Low or medium carbon steel M5 - M39 225 400 (58,000 PSI)
B67 B99.5
240
8.8 Medium carbon steel: quenched & tempered M5 - M16
M18 - M39
580
600
800 (116,000PSI) 830 (120,000 , PSI)
C22
C23
C32
C34
640
660
10.9 Alloy steel: quenched & tempered M5 - M39 830 1040 (150,800 PSI)
C32 C39
940
12.9 Alloy steel: quenched & tempered M1.6 - M39 970 1220 (177,000 PSI)
C39 C44
1100

MECHANICAL PROPERTIES FOR NUTS — AUSTENITIC STEEL GRADES ISO 3506-2:2009 (INTERNALLY THREADED FASTENERS)

Metric Property Class Grade Property Class Stress under proof load (Sp) min. Steel group MPA Grade Identification Marking
    Nuts with thk ≥ 0,8D Nuts with thk ≥ 0,8D  
Austenitic A2 70 700
Austenitic A2 80 800
Austenitic A4 70 700
Austenitic A4 80 800

MECHANICAL PROPERTIES PER DIN 267 PART 4 (INTERNALLY THREADED FASTENERS)

Property Class Typical Material Proof Stress MPa Core Hardness Rockwell Min. Grade Identification Marking
Class 8 Low to medium carbon steel 800 C30
Class 10 Medium carbon steel; quenched & tempered 1000 C36
Class 12 Medium carbon steel; quenched& tempered 1200 C36