ASTM A193 Grade B7 Specifications
ASTM A193 Gr.B7 Stud/Bolt/Screw:
Chemical Requirements @AISI 4110
| Elements |
Range |
Product Variation, Over or Under |
Carbon |
0.37 – 0.49 |
0.02 |
Manganese |
0.65 – 1.10 |
0.04 |
Phosphorus, max |
0.035 |
0.005over |
Sulphur, max |
0.040 |
0.005over |
Silicon |
0.15-0.35 |
0.02 |
Chromium |
0.75-1.20 |
0.05 |
Molybdenum |
0.15-0.25 |
0.02 |
Mechanical Requirements- @Metric Sizes
Diameter, Metric |
MinimumTempering Temperature,ºC |
Tensile Strength, Min, MPa |
Yield Strength, Min, 0.2%offset, MPa |
Elongation In 4D,Min, % |
Reduction of Area, Min, % |
M64 and under |
593 |
860 |
720 |
16 |
50 |
Over M64 toM100 |
593 |
795 |
655 |
16 |
50 |
Over M100 toM180 |
593 |
690 |
515 |
18 |
50 |
Hardness – Max (Metric) |
|
M64 and under |
35 HRC |
Over M64 to M100 |
35 HRC |
Over M100 to M180 |
25 HRC |
Process Carried Out |
|
Stage I |
Hardening at 880ºC For 2 Hours in Electric Furnace. |
Stage II |
Quench in Hot oil 60 to 95ºC. |
Stage III |
As Quenched Hardness 52/54 HRC. |
Stage IV |
Tempering at 650ºC for 3Hrs. |
Stage V |
Cool in Air |