Electrode comparison
E4043 vs ER4043
Same 5% silicon aluminium chemistry, completely different process. E4043 is a flux-covered stick electrode; ER4043 is bare wire for TIG and MIG.
E4043 vs ER4043 at a glance
| E4043 | ER4043 | |
|---|---|---|
| AWS specification | AWS A5.3/A5.3M | AWS A5.10/A5.10M |
| Process | Stick (SMAW) | TIG (GTAW) / MIG (GMAW) |
| Form | Covered electrode | Solid wire / rod |
| Tensile strength (min) | 14 ksi | 27 ksi |
| Yield strength (min) | — | 16 ksi |
| Elongation (min) | — | 8% |
| Impact toughness | Not applicable | Not applicable |
| Polarity | DCEP | AC (GTAW), DCEP (GMAW) |
| Positions | Flat, Horizontal fillet | Flat, Horizontal, Vertical, Overhead |
| Penetration | Medium | Medium |
| Deposition rate | Medium | High on MIG, moderate on TIG |
| Coating / core | Salt-based flux, extremely hygroscopic | None — bare wire or rod |
| Slag | Corrosive salt flux — must be removed completely with hot water after welding | None; remove the oxide layer mechanically before welding |
| Shielding gas | None — self-shielding | 100% argon |
| Storage | Extremely moisture sensitive. Keep hermetically sealed and store in a heated cabinet; open only what you will use immediately. | Keep sealed and dry. Aluminum filler grows an oxide layer and picks up moisture that turns into weld porosity. |
| Primary use | Field repair of aluminum castings where no TIG or MIG is available | Welding and repairing 6061 structures, frames and extrusions |
Which should you use?
The alloy is the same; the process is not. E4043 is a covered electrode under AWS A5.3 for stick welding aluminium — a field-repair method that is limited to the flat position, carries a corrosive salt flux that must be washed off, absorbs moisture within hours and produces porous welds far more often than not. ER4043 is bare wire or rod under AWS A5.10 for TIG and MIG, and it produces clean, controllable, far stronger welds. If a TIG or spool-gun MIG setup exists at all, use it.
Choose E4043 when
- Field repair with no TIG or MIG available
- Legacy procedures that specify covered aluminium electrodes
- Emergency work on heavy aluminium castings
Choose ER4043 when
- Essentially all modern aluminium welding
- Any work where weld quality matters
- Out-of-position work, thin material and cosmetic welds
Amperage compared
| Diameter | E4043 | ER4043 |
|---|---|---|
| 3/32 in (2.4 mm) | 40–70 A | — |
| 1/8 in (3.2 mm) | 60–95 A | — |
| 5/32 in (4.0 mm) | 90–130 A | — |
| 3/16 in (4.8 mm) | 120–170 A | — |
| 0.030 in (0.8 mm) MIG | — | 60–175 A |
| 0.035 in (0.9 mm) MIG | — | 70–200 A |
| 3/64 in (1.2 mm) MIG | — | 100–260 A |
| 1/16 in (1.6 mm) TIG | — | 40–90 A |
| 3/32 in (2.4 mm) TIG | — | 80–130 A |
| 1/8 in (3.2 mm) TIG | — | 120–190 A |
Ranges are typical starting points. Diameters listed for only one electrode are shown as — for the other.
E4043 vs ER4043 — common questions
Can you stick weld aluminium?
Yes, with covered electrodes such as E4043, but the results are markedly worse than TIG or MIG: flat position only, corrosive flux residue, and frequent porosity. It is a field-repair method, not a production one.
Is the weld metal the same strength?
No. AWS A5.3 sets a 14 ksi minimum for E4043 covered electrodes, while ER4043 deposited by TIG or MIG typically reaches around 27 ksi under cleaner conditions.
Does the flux have to be removed?
From E4043, yes — completely, with hot water and a dedicated stainless brush. The salt-based residue is corrosive and will attack the aluminium. ER4043 has no flux at all.
Full specifications
E4043
AWS A5.3/A5.3M
E4043 is the covered aluminum stick electrode — a legacy repair consumable for field work where no TIG or MIG machine is available, largely superseded by ER4043 wire.
ER4043
AWS A5.10/A5.10M
ER4043 is the 5% silicon aluminum filler — fluid, crack-resistant and the default choice for welding 6061 and aluminum castings.