Macro-etch and flow lines
Sectioned forgings are etched to confirm grain flow follows the part contour, with no laps, folds or flow-through defects.
High-strength chassis forging alloy
6A10 T6 Forged Aluminium Automotive Components
6A10 is a GB/T 3190 forging alloy that adds copper, manganese, chromium and zirconium to a 6082-type Al-Mg-Si base. In T6 it reaches minimum tensile strength of about 380 MPa along the grain flow, roughly 20 % above 6082 forgings, which lets designers replace steel control arms and knuckles with lighter aluminium parts. Metline supplies 6A10-T6 die forgings, forging stock and machined components worldwide.
- Alloy
- 6A10 (GB/T 3190)
- Temper
- T6
- Min. strength (L)
- Rm 380 / Rp0.2 350 MPa
- Typical parts
- Control arms, knuckles, links
Why 6A10 is used for chassis forgings
Unsprung chassis parts are where lightweighting pays most: every kilogram removed from a control arm or knuckle improves ride, handling and efficiency more than the same saving in the body. Forged 6082-T6 has been the standard aluminium choice for decades, but its strength limits how far section sizes can be reduced. 6A10 was developed to push that limit while keeping the forgeability, toughness and corrosion behaviour of 6xxx alloys.
Compared with 6082, 6A10 adds 0.30 – 0.80 % copper for extra precipitation strengthening and a small zirconium addition that, together with manganese and chromium, forms fine dispersoids. These pin grain boundaries during forging and solution treatment, so the part keeps a fine, fibrous grain structure that follows the forging flow lines. The result is higher strength, better fatigue performance and lower risk of coarse surface grains.
In Chinese passenger-car standards for aluminium control-arm forgings (GB/T 33823), 6xxx alloys of this kind are specified alongside 6082 and 6061. Internationally, similar copper-bearing high-strength forging alloys are used by suspension makers under OEM specifications.
6A10 chemical composition (wt %)
Limits as listed for 6A10 in GB/T 3190. Confirm against the edition on your drawing; the lot certificate reports the actual analysis.
| Element | Minimum | Maximum |
|---|---|---|
| Silicon (Si) | 0.70 | 1.10 |
| Iron (Fe) | — | 0.50 |
| Copper (Cu) | 0.30 | 0.80 |
| Manganese (Mn) | 0.30 | 0.90 |
| Magnesium (Mg) | 0.70 | 1.10 |
| Chromium (Cr) | 0.05 | 0.25 |
| Zinc (Zn) | — | 0.20 |
| Titanium (Ti) | 0.02 | 0.10 |
| Zirconium (Zr) | 0.04 | 0.20 |
| Others, each / total | — | 0.05 / 0.15 |
| Aluminium (Al) | Remainder |
6A10-T6 forging properties
Values are minimums for die forgings up to 100 mm thick, tested along (L) and across (non-L) the grain flow. Forging drawings mark which zones are tested in which direction.
| Direction | Tensile strength Rm (min.) | Proof strength Rp0.2 (min.) | Elongation A (min.) | Hardness (min.) |
|---|---|---|---|---|
| Along grain flow | 380 MPa | 350 MPa | 10 % | 105 HBW |
| Across grain flow | 370 MPa | 330 MPa | 8 % | — |
| Alloy-temper (die forging) | Typical minimum Rm | Typical minimum Rp0.2 |
|---|---|---|
| 6061-T6 | about 260 – 290 MPa | about 240 MPa |
| 6082-T6 | about 310 MPa | about 260 MPa |
| 6A10-T6 | 380 MPa | 350 MPa |
Comparison figures for 6061 and 6082 are indicative; exact minimums depend on the standard and section thickness.
Inspection of safety-critical forgings
Control arms and knuckles are safety parts, so inspection goes well beyond a tensile test. A typical control plan includes:
Oxide film inclusions
Macro and fracture tests check for oxide films, with limits on the size and total area of any indications per inspected area.
Coarse grain
The depth of any coarse recrystallised surface layer is measured; dispersoid-forming alloys like 6A10 help keep it shallow.
Ultrasonic testing
Forging stock and finished parts can be ultrasonically tested to detect internal defects.
Dimensions
Machined interfaces such as ball-joint bores and bushing seats are measured on CMM.
Fatigue validation
Component fatigue tests are run by the part owner to approve the design, alloy and process route.
How 6A10 chassis parts are made
- StockHomogenised cast or extruded bar is cut to slugs; extruded stock gives a finer starting structure.
- Pre-formingRoll forming or cross-wedge rolling distributes metal along the arm before die forging.
- Die forgingHot forging in closed dies at roughly 450 – 520 °C, followed by trimming and piercing.
- Heat treatmentSolution treatment, rapid quench and artificial ageing to T6, with fixtures to limit distortion.
- FinishingShot blasting, machining of bores and faces, and protective coating where specified.
Forging supply range
- Die forgings
- Projected area up to roughly 2.5 m² depending on press
- Free (open-die) forgings
- Blocks, discs and bars to drawing
- Rolled rings
- Wide diameter range to drawing
- Standards
- GB/T 3190 composition; forging standards such as GB/T 33823 (control arms) and the OEM drawing
Automotive uses of 6A10 forgings
- Upper and lower control arms in passenger cars and SUVs
- Steering knuckles and hub carriers
- Suspension links, tie rods and stabiliser links
- Sub-frame nodes and mounting brackets
- Brake caliper brackets and steering components
Pistons, connecting rods and brake discs are not 6A10 applications: pistons use high-silicon casting or forging alloys, and brake discs are cast iron or composites.
How to order 6A10 forgings
- SpecifyAlloy and temper (6A10-T6), forging and machining drawings, test directions and zones, annual volume and finishing.
- Confirm the standardGB/T 3190 and GB/T 33823 or your OEM specification; state if 6082-T6 is an accepted alternative.
- QuoteWe confirm availability, tolerances, certification and delivery terms (EXW, FOB, CIF or DAP) for your plant or port.
- Process and inspectParts are forged, heat-treated, inspected per the control plan and packed in returnable or export packaging.
- Document and shipEach lot ships with an EN 10204 3.1 mill test certificate, lot traceability and a packing list, in seaworthy export packing. Third-party inspection can be arranged on request.
References and standards
- GB/T 3190 – Wrought aluminium and aluminium alloys: chemical composition
- GB/T 33823 – Aluminium alloy die forgings for control arms of passenger vehicles
- ASTM B247 – Aluminum and Aluminum-Alloy Die Forgings, Hand Forgings, and Rolled Ring Forgings
- ASM Handbook, Vol. 2 – Properties and Selection: Nonferrous Alloys and Special-Purpose Materials
- IATF 16949 – Quality management system requirements for automotive production and relevant service parts organisations
6A10 forged aluminium (aluminum) parts: frequently asked questions
How does 6A10 differ from 6082?
6A10 adds 0.30 – 0.80 % copper and 0.04 – 0.20 % zirconium to a 6082-like base. That raises T6 minimum strength to about 380 / 350 MPa and keeps a finer grain structure.
What parts are made from 6A10?
Mainly suspension control arms, knuckles, links and other chassis forgings where high strength and low weight matter.
Why are properties given along and across the grain flow?
Forging aligns the grain structure with the metal flow. Strength and ductility are highest along the flow, so critical stress paths are designed to follow it.
Is 6A10 corrosion resistant?
Its copper content makes it slightly less resistant than copper-free 6082, but with shot blasting and a coating or e-coat it performs well under the vehicle.
Do you supply 6A10 forging stock as well as parts?
Yes: extruded or cast forging stock, die forgings and machined parts, shipped worldwide with 3.1 certificates.
Need lightweight chassis forgings?
Send the part drawing, volume and inspection plan. We will reply with feasibility, certification and delivered pricing.
