ASTM F468 UNS C27000 represents grade specification for Brass Grade C27000 Bolts, Screw Fasteners. It covers both coarse and fine threaded Brass bolts, screws, stud bolts. Below is the chemical, mechanical and other requirements. ASTM F468 UNS C27000 Fasteners carry EN 10204 Type 3.1 Certification.
| Composition, % Copper and Copper Base Alloys |
|||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UNS Designation | Alloy | General Name | Aluminum | Copper, min | Iron, max | Manganese, max | Nickel, max | Phosphorus | Silicon | Zinc, maxA | Lead, max | Tin | Arsenic, max |
| C27000 | 270 | Brass | -- | 63.0 - 68.5 | 0.07 | -- | -- | -- | -- | balance | 0.10 | -- | -- |
A Elements shown as balance shall be arithmetically computed by deducting the sum of the other named elements from 100.
B Copper plus specified elements = 99.8 min; copper plus silver = 88.5-91.5.
C Cobalt is to be counted as nickel
D Minimum content of copper plus all other elements with specified limits shall be 99.5%.
E An alloy containing as high as 2.5% silicon is acceptable provided the sum of all the lements other than copper, silicon and iron does not exceed 0.30 %.
| Alloy | Mechanical Property Marking | Nominal Thread Diameter, inch | HardnessA | Full Size Tests B | Machined Specimen Tests | |||
|---|---|---|---|---|---|---|---|---|
| Tensile Strength, min, ksi | Yield Strength, min, ksiC | Tensile Strength, min, ksi | Yield Strength, min, ksiC | Elongation in 4D, min %D | ||||
| Copper | ||||||||
| Cu 270 | F 468B | all | 55 - 80 HRF | 60 - 90 | 50 | 55 | 50 | 35 |
A where both tension and hardness tests are performed, the tension tests shall take precedence for acceptance purposes. For alumium and titanium alloys, hardness tests are for information only.
B The yield tensile strength values for full size products shall be computed by dividing the yield and maximum tensile load by the stress area for the product diameter and thread pitch as given in table on tensile stress areads.
C Yield strength is the stress at which an offset of 0.2% gauge length occurs.
D Elongation is determined using a gauge length of 4 diameters of test specimen in accordance with Test Methods E8.
E "HF" denoted a hot formed product
F Aluminum alloy temper designations are in accordance with ANSI H35.1.
G Full size test mechanical properties apply to fasteners with a maximum diameter of 76 mm. Mechanical properties of larger sections shall be negotiated between the material manufacturer and the fastener producer.
H Ti 5 Class A requires wedge test tensile testing in accordance with section 6.6 & Ti 5.5 Class B requires wedge tensile testing in accordance with section 6.5.1 of ASTM F468.
| Nominal Size, inch. | Coarse Threads - UNC | Fine Threads - UNF | 8 Thread Series - 8UN | |||
|---|---|---|---|---|---|---|
| Threads / inch | Stress AreaA, in2 | Threads / inch | Stress AreaA, in2 | Threads / inch | Stress AreaA, in2 | |
| 1/4 | 20 | 0.0318 | 28 | 0.0364 | -- | -- |
| 5/16 | 18 | 0.0524 | 24 | 0.0580 | -- | -- |
| 3/18 | 16 | 0.0775 | 24 | 0.0878 | -- | -- |
| 7/16 | 14 | 0.1063 | 20 | 0.1187 | ||
| 1/2 | 13 | 0.1419 | 20 | 0.1599 | ||
| 9/16 | 12 | 0.1820 | 18 | 0.2030 | ||
| 5/8 | 11 | 0.2260 | 18 | 0.2560 | ||
| 3/4 | 10 | 0.3340 | 16 | 0.3730 | ||
| 7/8 | 9 | 0.4620 | 14 | 0.5090 | ||
| 1 | 8 | 0.6060 | 12 | 0.6630 | ||
| 1 1/8 | 7 | 0.7630 | 12 | 0.8560 | 8 | 0.790 |
| 1 1/4 | 7 | 0.9690 | 12 | 1.0730 | 8 | 1.000 |
| 1 3/8 | 6 | 1.1550 | 12 | 1.3150 | 8 | 1.233 |
| 1 1/2 | 6 | 1.4050 | 12 | 1.5810 | 8 | 1.492 |
A Tensile stress areas are computed using the following formula: As = 0.7854 [D- (0.9743/n)]2
Where:
As = Tensile stress area, in.2,
D = Nominal size (basic major diameter), in., and,
n = number of threads per inch.
| Alloy | Test Method |
| Copper | E52, E54, E62, E75, E478 |