High Speed Billets – Vedanta
Aluminium – Extruding Excellence & Efficiency
In the fast-paced world of
aluminium extrusion, productivity and precision are paramount. At Vedanta
Aluminium, we recognized the growing demand for billets that can be extruded
faster, last longer, and deliver flawless finishes. Through relentless
innovation and deep metallurgical expertise, we’ve developed High-Speed
6xxx Series Billets—engineered to redefine extrusion performance.
The Challenge: Balancing Speed
and Quality
In the dynamic world of
aluminium extrusion, every second on the press floor isn’t just time — it’s
opportunity. As extruders, we’re constantly chasing higher throughput,
tighter tolerances, and longer die life — all while meeting ever-rising
expectations on surface finish and mechanical integrity. The truth is that
conventional billets have often made us choose to go fast and risk tool damage
or go safe and lose productivity. But that trade-off doesn’t work anymore.
Voice of Customer: A
billet that extrudes faster without compromising strength or finish.
Al-Mg-Si Phase Diagram:
The Al-Mg-Si ternary
system is the basis for 6XXX series aluminium alloys, which are
widely used in automotive and structural applications due to their good
formability, weldability, and moderate strength (enhanced by precipitation
hardening). The key phases and features of the Al-Mg-Si system include:
1.
Key
Ternary Reactions & Phases
The Al-Mg-Si system is more complex than binary Al-Si due
to the addition of magnesium, forming ternary compounds:
·
Mg₂Si
(Magnesium Silicide): The
most important strengthening phase in 6XXX alloys.
·
α-Al
(Aluminium-rich solid solution): Primary phase
·
Eutectic
Reactions: Multiple
invariant reactions occur, but most relevant for 6XXX alloys is the quasi-binary
Al-Mg₂Si section, which behaves similarly to a binary eutectic system.
2.
Quasi-Binary Al-Mg₂Si Section
·
Eutectic
Point (~1.85 wt.% Mg₂Si at ~595°C):
· At this composition, the liquid
transforms simultaneously into α-Al + Mg₂Si.
·
Hypoeutectic
Alloys (Mg₂Si < 1.85%):
· Solidification begins with primary
α-Al dendrites,
followed by the eutectic mixture (α-Al + Mg₂Si).
·
Hypereutectic
Alloys (Mg₂Si > 1.85%):
·
Primary
Mg₂Si crystals form first,
followed by the eutectic.
·
These
alloys are less common in 6XXX series due to brittleness from coarse Mg₂Si.
3.
Precipitation
Hardening (Mg₂Si Formation)
·
After
solution heat treatment and quenching, fine Mg₂Si precipitates form
during aging (e.g., T6 temper), providing strength.
·
Excess
silicon (beyond Mg₂Si stoichiometry) can form free Si particles,
improve strength but reduce ductility.
Metallurgy in Action for High-Speed
Extrusion:
The
key to high-speed extrusion lies in the billet’s microstructure. Vedanta’s
solution focuses on two critical advancements:
1.
Optimized Homogenization:
· A modified homogenization cycle
maximizes the transformation of brittle β-phase (AlFeSi) intermetallics
into ductile, spherical α-phase dispersoids.
· This reduces flow stress during
extrusion, enabling smoother material flow and lower press loads.
2.
Alpha-Phase Stabilizers:
· Targeted additions of alpha
stabilizers promote the formation of fine, spheroidized α(AlFeSi)
precipitates.
·
Eutectic
silicon is modified from angular to spherical morphology, further
enhancing deformability.
Proven Results: Transforming
Extrusion Performance:
Customer Trial |
Extrusion Speed (mm/sec) |
Improvement % |
|
Regular Billet |
High Speed Billet |
||
1 |
2.2 |
3.8 |
26.6 |
2 |
2.5 |
3.2 |
15.9 |
3 |
4.6~4.8 |
5.6~5.8 |
21 |
4 |
4.6~4.8 |
6.8~7.0 |
45 |
Here 1,2,3,4 are High Speed
billets taken trail at customer sites in comparison with same grade regular
billets enabling apple to apple peer comparison.
Key Benefits:
- ≥20% Faster Extrusion: Higher throughput without compromising profile
integrity. - Lower Breakout Pressure: Reduced energy consumption and press wear.
- Superior Surface Finish: Minimal pick-up for defect-free outputs.
- Extended Die Life: Reduced abrasive wear from softer α-phase particles
- Higher Recovery Rates: Less scrap, more usable output per billet.
Voice of the Customer: A Leap
Forward
Customers who have transitioned to
Vedanta’s High-Speed Billets report:
- “The speed increase is remarkable—we’re
hitting targets 25% faster with no rework.” - “The consistency in finish across complex
profiles is unmatched.” - “Die life has improved by 15%, cutting our
tooling costs significantly.”
Why This Matters – From the
Extruder’s Perspective
For extruders, Vedanta’s
High-Speed Billets aren’t just about faster production—they’re a metallurgical
breakthrough that solves real press-floor challenges. The secret
lies in the controlled α(AlFeSi) phase transformation achieved through
optimized homogenization and alpha stabilizers. By converting brittle
β-phase intermetallics into fine, spherical α-phase dispersoids, these
billets exhibit lower flow stress—directly enabling higher extrusion speeds
(>20% faster) without profile defects. The refined microstructure also
reduces abrasive die wear, as softer α-particles minimize surface pick-up and
tearing. From a metallurgy standpoint, the spheroidized eutectic silicon and
uniform α-dispersoids ensure consistent material flow, eliminating the “stop-and-go”
deformation typical of conventional billets.
Conclusion:
At Vedanta Aluminium, we go
beyond selling billets as products but to blend deep metallurgical expertise
with customer-centric innovation. We solve problems, enable
progress, and co-create solutions that transform operations. The
development of High-Speed Billets is yet another chapter in our mission to
deliver fit-for-purpose solutions — born in the melt shop, tested at the
press, and validated performance by customers.