Aluminum-Silicon Bronze C64200
The screw-machine aluminum bronze — 75 to 110 ksi with 60 percent machinability — for valve stems, pump parts and turned marine fasteners.
What C64200 Al-Si Bronze is.
C64200 pairs 7 percent aluminum with about 2 percent silicon. The silicon forms hard particles that break chips and give the alloy roughly twice the machinability of other aluminum bronzes, while keeping the family's seawater and acid resistance and a tensile strength of 75 ksi and above. It is also resistant to galling and has good hot-working properties.
ASTM F468 lists C64200 fasteners as Cu 642 (marking F468J). We machine C64200 studs, bolts, nuts and components from certified B150 rod.
Chemical composition.
| Element | Symbol | Min % | Max % |
|---|---|---|---|
| Copper | Cu | balance | — |
| Aluminum | Al | 6.3 | 7.6 |
| Silicon | Si | 1.5 | 2.2 |
| Iron | Fe | — | 0.30 |
| Nickel | Ni | — | 0.25 |
| Manganese | Mn | — | 0.10 |
| Tin | Sn | — | 0.20 |
| Zinc | Zn | — | 0.50 |
| Lead | Pb | — | 0.05 |
| Arsenic | As | — | 0.09 |
Values per ASTM B150/B150M-19 Table 1 (verified against the specification). Confirm the edition called out on your purchase order with our estimating team.
Mechanical properties.
| Nominal diameter (in.) | Hardness | Full-size tensile (ksi) | Full-size yield, min (ksi) | Machined tensile, min (ksi) | Machined yield, min (ksi) | Elongation in 4D, min (%) |
|---|---|---|---|---|---|---|
| All sizes | 75–95 HRB | 75–110 | 35 | 75 | 35 | 10 |
Values per ASTM F468-23 Table 2 (verified against the specification). Confirm the edition called out on your purchase order with our estimating team. Full-size tensile range and yield; machined-specimen minimums in the last three columns.
| Nut style | Hardness, min | Proof stress, min (ksi) |
|---|---|---|
| Hex and hex flange | 75 HRB | 75 |
| Heavy hex, large hex flange and thick | 75 HRB | 81 |
Values per ASTM F467-24 Table 2 (verified against the specification). Confirm the edition called out on your purchase order with our estimating team.
| Temper and size (in.) | Tensile strength, min (ksi) | Yield strength at 0.5 % extension, min (ksi) | Elongation, min (%) |
|---|---|---|---|
| HR50 — ½ and under | 90 | 45 | 9 |
| HR50 — over ½ to 1 | 85 | 45 | 12 |
| HR50 — over 1 to 2 | 80 | 42 | 12 |
| HR50 — over 2 to 3 | 75 | 35 | 15 |
Values per ASTM B150/B150M-19 Table 2 (verified against the specification). Confirm the edition called out on your purchase order with our estimating team.
Specifications that apply.
How C64200 Al-Si Bronze ships from Houston.
- Machined hex bolts, studs and cap screws to F468
- Hex and heavy hex nuts to F467
- Valve stems, pump shafts and screw-machine components
- Certified B150 rod
C64200 Al-Si Bronze fasteners we make.
Every item is manufactured to your drawing or standard in C64200 Al-Si Bronze, imperial or metric, with an EN 10204 3.1 certificate.
What is aluminum-silicon bronze?
C64200 is a 7 percent aluminum bronze modified with silicon for machinability. Ordinary aluminum bronzes produce long, tough chips; the silicon in C64200 forms a hard phase that fractures the chip, so the alloy turns and threads at about 60 percent of the free-cutting brass rating. Strength, at 75 to 90 ksi in bar, and corrosion resistance are close to C61400, and the alloy resists galling against itself better than most bronzes.
As a fastener
F468 covers C64200 as Cu 642 (F468J): 75 to 110 ksi tensile, 35 ksi yield, 75 to 95 HRB, with a 10 percent minimum elongation on machined specimens. Nuts to F467 (F467J) carry a 75 ksi proof stress. It is the natural choice when a bronze fastener or valve stem is to be machined in quantity.
Testing, certification and marking
- Tensile and hardness tested per lot on the finished product
- Grade or alloy marking F468J on bolts and F467J on nuts and manufacturer's identification on every piece
- EN 10204 3.1 material test report with heat number and chemistry; 3.2 witness available
- Alloy identified by UNS number on the certificate
Nickel-Aluminum Bronze C63000
Steel-like strength in a bronze — 100 to 130 ksi as a fastener — with seawater, cavitation and wear resistance for propellers, pumps, valve seats and subsea hardware.
ASTM F468 / F467 fasteners · ASTM B150 rod and barAluminum Bronze C61400
The 7 percent aluminum bronze — 75 to 110 ksi as a fastener, weldable, and resistant to seawater, brine and dilute acids.
ASTM F468 / F467 fasteners · ASTM B98 rodHigh-Silicon Bronze C65500
The strongest common silicon bronze in bar form, 90 ksi in hard temper and 100 ksi extra-hard in small rod — for machined marine fasteners, valve stems and pump parts.