C656 Silicon Bronze
Nominal Chemical
Composition
INTRODUCTION
Aufhauser Silicon Bronze is a copper based filler metal containing 3% silicon and small amounts of manganese, tin and zinc. Primarily used for MIG, TIG and oxyacetylene welding of copper, copper-silicon and copper-zinc base metals to themselves and to steel. Excellent for plain or galvanized steel sheet metal as well as other coated steels. The oxyacetylene gas flame should be slightly oxidizing. Keep the weld puddle small in order to promote fast solidification and to minimize cracking. A high boric acid flux such as Aufhauser Flux600 should be used both before and during welding. Preheating is NOT recommended.
ADVANTAGES
- Joints are made at lower temperature than in gas or arc welding
- Minimizes thermal stress and distortion
- Less susceptibility to cracking
- Soft and ductile weld deposits
- Easy machinability
- Low residual stress
- High strength fillets
- Mobile equipment for simple on-site repair
METALS TO BE BRAZE WELDED
- Steels, cast irons, copper alloys, nickel alloys and stainless steel
APPLICATIONS
- MIG, TIG and oxyacetylene welding of copper, copper-silicon and copper-zinc base metals to themselves and to steel
- Surfacing areas subject to corrosion
GENERAL INFORMATION
Chemical Composition| Copper | Zinc | Tin | Manganese | Iron | Silicon | Aluminum | Lead | Others |
|---|---|---|---|---|---|---|---|---|
| Remainder | 1.0 | 1.0 | 1.5 | 0.50 | 2.8 - 4.0 | 0.01 | 0.02 | 0.50 |
Note: Copper contains Silver. All values are maximum percentage, unless shown in range.
ADDITIONAL INFORMATION
Copper and its alloys require a relatively high heat input with shortened welding time. Higher preheat temperatures and faster welding rates than for steel are necessary.
PHYSICAL and MECHANICAL PROPERTIES
| Melting Point | 1866°F (1019°C) |
| Solidification | 1904°F (1904°C) |
| Density at 68°F | 0.308 lbs./in³ |
| Electrical Conductivity at 68°F | 7.0 %IACS (annealed) |
| Thermal Conductivity at 68°F | 21 Btu |
| Tensile Strength | 50,000 psi, min. |
| Elongation in 2" | 65% |
| Brinell Hardness (500 kgf) | 80-100 |
SPECIFICATIONS MEET OR EXCEED
| AWS A5.7 ERCuSi-A |
| ASME SFA5.7 |
| QQ-R-571C |
| MIL-R-19631B Type MIL-RCuSi-A |
| MIL-E-23765/3 (MIL-CuSi) |
STANDARD SIZES AND DIAMETERS
| Size | Cast (12" Spool) |
Helix (12" Spool) |
|---|---|---|
| 3/32 or 1/8 x 36" rod | N/A | N/A |
| 0.035" dia. x 30 lb. spl | 15-40" | < 1" |
| 0.045" dia. x 30 lb. spl | 15-40" | < 1" |
| 0.062" dia. x 30 lb. spl | 15-40" | < 1" |
GMAW (MIG) Parameters (DC Reverse Polarity) Electrode Positive Spray transfer
| Wire Diameter | Amps | Volts | Argon (cfh) | Wire Feed (ipm) |
|---|---|---|---|---|
| 0.030" | 130-150 | 21-23 | 25 | 460-500 |
| 0.035" | 145-185 | 23-25 | 30 | 400-440 |
| 0.045" | 195-215 | 26-28 | 30 | 280-310 |
| 1/16" | 260-280 | 27-30 | 40 | 150-210 |
GTAW (TIG) Parameters (DCSP)² Electrode negative or ACHF
| Material | 2% Thoriated² | Filler Wire Size | Amps (DC) | Amps (AC) | Gas Cup | Argon (cfh) |
|---|---|---|---|---|---|---|
| 1/16" | 1/16" | 1/16" | 70-150 | 70-150 | 3/8-1/2 | 15 |
| 3/32"-1/8" | 3/32" | 3/32" | 150-200 | 140-230 | 7/16-1/2 | 15 |
| 3/16"-1/2" | 1/8" | 3/32"-1/8" | 230-400 | 225-320 | 7/16-1/2 | 20 |
| 1/2"-1" | 3/16" | 3/16"-1/4" | 325-500 | 290-485 | 1/2 | 25 |
TYPICAL USES FOR ALLOY C656
| Product Category | Product | Reason Category | Reason |
|---|---|---|---|
| Industrial | Welding Rod, Filler Metal | Brazing Characteristics | Fluidity |
| Welding Rod, Filler Metal | Conductivity (Electrical) | Electrical Conductivity | |
| Welding Rod, Filler Metal | Conductivity (Thermal) | Thermal Conductivity | |
| Welding Rod, Filler Metal | Mechanical Properties | Moderate to High Strength |