Aluminum ER4643
ASTM AWS A5.10 ER4643
ER4643 is an Al-Si-Mg filler in AWS A5.10, formulated with reduced silicon and added magnesium to lower weld cracking and give higher as-welded and post-T6 strength than ER4043 on 6000-series joints.
Reference datasheet — ER4643 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the AW condition
ER4643 tempers and conditions
ER4643 is supplied in 3 conditions, soft to hard. AW is the default FabDigit quotes; the values on this page are for it.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As fabricated | The product as sold: drawn and cleaned MIG spool wire or straight TIG rod; strength values apply to the wire itself, not to a joint. | 95 | 165 | 15 | 45 HB | 41 % IACS |
AWDefault As-welded deposit | Default condition for field/production welds on 6000 series where no post-weld heat treatment is applied. | 115 | 186 | 8 | 45 HB | 40 % IACS |
post-weld solution heat treated and artificially aged | Pick when the whole weldment can be re-solutionized and aged — this is where 4643 beats 4043, recovering most of the 6061-T6 joint strength. | 220 | 290 | 5 | 80 HB | 42 % IACS |
What is ER4643?
ER4643 is an Al-Si-Mg filler in AWS A5.10, formulated with reduced silicon and added magnesium to lower weld cracking and give higher as-welded and post-T6 strength than ER4043 on 6000-series joints. It is supplied as drawn spooled wire and straight cut rod for GMAW and GTAW of 6061/6063/6082 and Al-Si-Mg castings, with AW, AW-T6 and F conditions on file. As-welded properties are about 115 MPa yield, 186 MPa tensile and 8 % elongation, and the full advantage over ER4043 requires a post-weld T6. Service is limited to roughly 150 °C and the Si-bearing deposit will not colour-match anodized base metal. ER4643 has a density of 2.69 g/cm³ (0.0972 lb/in³), lighter than 67% of aluminum grades. It melts at 574°C (1,065 °F). ER4643 has a yield strength of 115 MPa (16.7 ksi) and a tensile strength of 186 MPa (27 ksi) — weaker than 79% of aluminum grades. Elongation at break is 8% and the elastic modulus is 70 GPa (10.2 Msi).
What is ER4643 used for?
- Automotive 6000-series body and chassis welds
- Structural aluminum frames
- 6061 frame and tube weldments
- 6063 extrusion space-frame joints
- Al-Si-Mg casting to extrusion joints
- Heat-treated 6000-series assemblies requiring post-weld T6
Advantages
- Readily welded — 92/100, better than 95% of aluminum grades
- Conducts heat well — 160 W/m·K (92.4 BTU/hr·ft·°F), better than 76% of aluminum grades
Limitations
- Low strength — 115 MPa (16.7 ksi), worse than 79% of aluminum grades
- Hard to polish — 45/100, worse than 76% of aluminum grades
ER4643 properties
Typical room-temperature values for ER4643-AW; bars are the position among aluminum grades.
Physical3
ER4643 has a density of 2.69 g/cm³ (0.0972 lb/in³), lighter than 67% of aluminum grades. It melts at 574°C (1,065 °F).
Mechanical10
ER4643 has a yield strength of 115 MPa (16.7 ksi) and a tensile strength of 186 MPa (27 ksi) — weaker than 79% of aluminum grades. Elongation at break is 8% and the elastic modulus is 70 GPa (10.2 Msi).
Thermal6
ER4643 is rated for continuous service to 150°C (302 °F). It conducts heat at 160 W/m·K (92.4 BTU/hr·ft·°F), better than 76% of aluminum grades. Thermal expansion is 22 µm/m·K (12.2 µin/in·°F).
Electrical3
ER4643 conducts electricity at 40 % IACS, better than 72% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is good (62/100), better than 67% of aluminum grades.
Sustainability4
Producing a kilogram of ER4643 takes about 200 MJ of energy and emits 12.5 kg of CO₂ — less than 60% of aluminum grades. Typical recycled content is 10%.
Manufacturability8
ER4643's machinability is fair (45/100, worse than 72% of aluminum grades); weldability excellent (92/100); formability good (55/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the aluminum family
Yield strength against density for every aluminum grade FabDigit runs. ER4643 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with ER4643
Is ER4643 easy to machine?
Weld beads machine like soft Al-Si: use sharp polished carbide, high speed, low feed and flood coolant to avoid built-up edge; Si particles cause moderate tool wear.
Can ER4643 be welded?
GMAW/GTAW filler for 6061/6063/6082 and Al-Si-Mg castings; run DCEP spray or AC TIG, keep interpass below ~120 °C, and plan post-weld T6 to realize the strength advantage over 4043.
Can ER4643 be formed, bent or molded?
Supplied as drawn wire or straight rod; keep spools dry and free of oil, and re-clean or replace wire showing hydrated oxide to prevent weld porosity.
ER4643 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Sireduced vs 4043 so that Mg2Si can strengthen after PWHT | 3.6 – 4.6 | 4.1 |
| Feimpurity limit | ≤ 0.8 | |
| Cu | ≤ 0.1 | |
| Mn | ≤ 0.05 | |
| Mgprecipitation-hardening addition | 0.1 – 0.3 | 0.2 |
| Zn | ≤ 0.1 | |
| Tigrain refiner | ≤ 0.15 | |
| Berestricted in most specifications | ≤ 3×10⁻⁴ | |
| Others (each) | ≤ 0.05 | |
| Others (total) | ≤ 0.15 | |
| Al | balance |
What surface finishes work on ER4643?
Do not use where anodized color match matters — the Si-bearing deposit anodizes dark gray; paint, powder coat or chemical conversion coating give uniform appearance.
Surface treatments FabDigit runs on aluminum parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Equivalent designations
Standards and trade names that resolve to Aluminum ER4643 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- AWS A5.10 ER4643
- Other
- 4643
How much does ER4643 cost?
ER4643 is a premium-cost aluminum ($$$), cheaper than about 51% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
ER4643 — frequently asked
What is ER4643 used for?
ER4643 is typically used for automotive 6000-series body and chassis welds, structural aluminum frames, 6061 frame and tube weldments, 6063 extrusion space-frame joints, al-Si-Mg casting to extrusion joints and heat-treated 6000-series assemblies requiring post-weld T6. In short: stronger than ER4043; low-crack 6000-series filler; best with post-weld T6.
What is the yield strength of ER4643?
ER4643 has a typical yield strength of 115 MPa (16.7 ksi) and a tensile strength of 186 MPa (27 ksi) — weaker than 79% of aluminum grades. Strength varies by condition: see the 3 listed tempers.
Is ER4643 easy to machine?
Reasonably — machinability is rated fair (45/100, worse than 72% of aluminum grades). Weld beads machine like soft Al-Si: use sharp polished carbide, high speed, low feed and flood coolant to avoid built-up edge; Si particles cause moderate tool wear.
Can ER4643 be welded?
Yes — weldability is rated excellent (92/100). GMAW/GTAW filler for 6061/6063/6082 and Al-Si-Mg castings; run DCEP spray or AC TIG, keep interpass below ~120 °C, and plan post-weld T6 to realize the strength advantage over 4043.
What surface finishes work on ER4643?
Do not use where anodized color match matters — the Si-bearing deposit anodizes dark gray; paint, powder coat or chemical conversion coating give uniform appearance.
Can ER4643 be formed, bent or molded?
Supplied as drawn wire or straight rod; keep spools dry and free of oil, and re-clean or replace wire showing hydrated oxide to prevent weld porosity.
What is the maximum service temperature of ER4643?
ER4643 is rated for continuous use to about 150°C (302 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between ER4643-AW and ER4643 AW-T6?
AW is the default condition — default condition for field/production welds on 6000 series where no post-weld heat treatment is applied. AW-T6: pick when the whole weldment can be re-solutionized and aged — this is where 4643 beats 4043, recovering most of the 6061-T6 joint strength. Yield strength is 115 MPa in AW versus 220 MPa in AW-T6.
How much does ER4643 cost?
ER4643 is a premium-cost aluminum ($$$), cheaper than about 51% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- AWS A5.10/A5.10M — Specification for Bare Aluminum and Aluminum-Alloy Welding Electrodes and Rods — American Welding Society (2021)
- AWS D1.2/D1.2M — Structural Welding Code, Aluminum — American Welding Society (2014)
- International Alloy Designations and Chemical Composition Limits for Wrought Aluminum (Teal Sheets) — The Aluminum Association (2018)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- Aluminum Filler Alloy Selection and Weld Metal Property Data — AlcoTec Wire Corporation (2020)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.