ELEVENTH INTERNATIONAL ALUMINUM EXTRUSION TECHNOLOGY

SEMINAR AND EXPOSITION

How to Benefit from

Isothermal Extrusion

Alexander Klaus

Constellium: a leader in innovative aluminium solutions for the automotive, aerospace & packaging industries

2

Over 10,000 full-time employees

€5.2 billion in sales

22 manufacturing sites

C-TEC, our world-class Technology Center

Headquartered in Amsterdam, The Netherlands.

Corporate offices in Paris, France, Zurich, Switzerland and

New York, USA

2015 key figures

A global network of 22 facilities

3An introduction to Constellium 2016

Problem: surface defects

Challenges

Reliability Stable process conditions,

controlled process

Productivity Ram speed, quality

Documentation Production data

Using temperature process control

Achieve constant profile exit temperature

Adapt ram speed and billet temperature /

taper to improve productivity

Collect detailed process data

Isothermal extrusion: billet taper

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40 Exit temp. (°C)

Ram speed (mm/s)

± 1,5°C

Set billet

temperature

480°C Taper

70°C/m

Exit temp.

variation

within measuring

accuracyConstant

ram speed

Ideal state

Constant speed

Constant exit temp.

Achieved by correct

billet taper

Die limit diagram + process control problem

Billet temperature

Ram

speed

Set exit temp

1

2

±20°C

±10%

surface

defects

max.

pressure

mech.

prop.

Process control

does not detect

Dimensional defects

Mech. properties

Surface defects

(only exit

temperature)

Process control

increases speed

Is that feasible?

Isothermal extrusion: application

Speed related quality problems

Surface defects

Linked to exit temperature

Not linked to exit temperature

Dimensional defects

Speed-sensitive dies

Quench distortion

Mechanical defects

High quench exit temperature

Metallurgical defects

Peripheral coarse grain

Quality gates during extrusion

Press Quench

Cold saw

Cooling table

Log furnace

Stacker

QualityLab

Q1

Q2

Q3

Quality gates during extrusion and

recipe management strategy

Quality gates

1. QGate – at the press

Outer surface

Simple dimensions

Quench settings

2. QGate – at the cold saw

Inner surface

Full geometry

3. QGate – at the quality lab

Mechanical properties

Metallurgical properties

Recipe management strategy

1. “Free Run”

Use TPC to increase speed

2. “Delayed Run”

Use TPC to current recipe

1 billet trial within order (higher speed)

Check at Q2

Use TPC to increase recipe

/ repeat / feed back

3. “Last Billet Run”

Use TPC to current recipe

1 billet trial at end of order

Check at Q3 / update recipe / repeat

product quality

can be fully

assessed

Conclusion

Reliable and highly productive environment required

Temperature process control does not prevent quality problems –

it even causes new ones

Used correctly, process control enables increased repeatability

Recipe management depending on quality gates

Free run

Delayed run

Last billet run