SAE J429 (Revised JAN1999), Table 1
Marking not verified to two sources. Low carbon boron martensitic steel, quenched and tempered.
| Size range | Proof | Yield min | Tensile min | Core hardness |
|---|---|---|---|---|
| 1/4 in through 1 in | 120 ksi (827 MPa) | 130 ksi (896 MPa) | 150 ksi (1034 MPa) | Rockwell C33 to C39 |
Inch grades are published in ksi and metric classes in MPa. The other column on every row is a conversion at 1 ksi = 6.894757 MPa, rounded to the nearest whole unit - it is arithmetic on the published figure, not a second published figure.
Not described here. J429 prints the marking as a diagram and no two of the charts cross-checked for this page describe it in words.
Grade 8.2 matches Grade 8 on paper but is a boron steel with lower tempering temperature, and it is not accepted everywhere Grade 8 is. Read the marking, not the strength table.
Count the radial lines and add two. That rule identifies exactly two grades - SAE Grade 5 with three lines and SAE Grade 8 with six - and it fails everywhere else. Grades 1, 2 and 4 carry no marking at all, so an unmarked head is not evidence of Grade 2; it is evidence of nothing, and unmarked hardware that meets no standard looks exactly the same. ASTM grades are stamped with the specification (A325, A490, BC, BD, 307A) rather than lines, and metric classes are stamped with the class number. Four marking systems share one bin.
Low carbon boron martensitic steel, quenched and tempered. High-volume cold-headed parts specified as an equivalent to Grade 8.
Bolts and screws only, and only up to 1 in.
Tempered at 340 degrees C against Grade 8's 427 degrees C - J429 Table 2. That is the reason some specifications accept Grade 8 and not Grade 8.2 despite identical strength figures.
Over 1/4 in through 1 in, SAE Grade 8.2 requires a minimum tensile strength of 150 ksi (1034 MPa), a minimum yield of 130 ksi (896 MPa) and a proof load of 120 ksi (827 MPa).
Not described here. J429 prints the marking as a diagram and no two of the charts cross-checked for this page describe it in words.
Low carbon boron martensitic steel, quenched and tempered. High-volume cold-headed parts specified as an equivalent to Grade 8.
Twenty-two grades and classes: the SAE J429 inch grades, five ASTM specifications and the ISO 898-1 property classes. It is not every grade in circulation. Stainless classes (ISO 3506 A2 and A4, ASTM F593), the ASTM A193 and A320 high and low temperature grades, ASTM F1554 anchor rod grades and SAE grades 3, 5.1 and 8.1 are not carried here.
Dimensions are as defined by SAE J429 (Revised JAN1999), Table 1. This site is an independent reference and is not affiliated with, endorsed by or approved by any standards body.
Every value on this page was cross-checked against 5 independent published sources:
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