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Mitsubishi Evolution X. Manual - part 45

ALUMINUM PANEL

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WELDED PANEL REPLACEMENT

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ALUMINUM PANEL

ALUMINUM PANEL CHARACTERISTICS

M4030000500173

Description of aluminum panel

A new aluminum panel with higher strength and bet-
ter workability has been developed by adding a small
amount of metallic elements, including magnesium
(Mg), copper (Cu) and silicon (Si), to aluminum. This
type of aluminum material has equivalent strength to
cold rolled steel sheets.

Advantage of aluminum panel

1. Lighter: The specific gravity of aluminum is 2.7,

which is only one third of general steel panel (7.9).
However, it requires 1.4 times in thickness to
obtain the same rigidity as the steel panel,
resulting in one half in weight.

2. More durable: Aluminum has the property of

creating oxide coating on its surface when it
contacts with the air. This coating prevents it from
being corroded.

3. More heat-conductive: The heat conductivity of

aluminum is twice as high as that of iron. This
means that aluminum absorbs and disperses heat
more quickly, which results in prompt change of its
temperature.

4. More electric-conductive
5. Non-magnetic substance

ALUMINUM PANEL LOCATIONS

M4030000600277

AB701121AB

Fender

Hood

Roof panel

Application

Thickness

Roof panel

1.1 mm (0.043 inch)

Hood outer panel

0.9 mm (0.035 inch)

Hood inner panel

0.8mm (0.031 inch)

Fender

1.0 mm (0.039 inch)

Application

Thickness

ALUMINUM PANEL

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ALUMINUM PANEL REPAIR

M4030000700230

Precautions upon sheet metal processing

1. Major difference in processing between sheet metal and

steel sheet (On the basis of general body shop)

2. If strong impact is given under low temperature, its strength

becomes low and cracking occurs.

3. The springback (returning force to the original condition) is

large due to high elastic modules.

4. The thermal effect is large due to high heat conductivity.
5. When excessively heated, its strength will be deteriorated.

When heated additionally, it will be melted without
discolouration. [The heating temperature is approximately
250

°C (482°F)].

CAUTION

Weld and repair it if the side sill reinforcement front is
damaged.
6. Because the material is soft, choose an abrasive carefully.

Wear a dustproof mask and safety glasses, because ground
particle is light and tends to float in the air.

7. If a disk sander is strongly pressed against the aluminum

plate, friction heat is generated, resulting in exfoliation of the
aluminum alloy and clogging of the disk sander with the
exfoliated particles.

8. Because the clogged disk sander will damage the aluminum

alloy panel, replace it with a new one as soon as possible.

Work
description

Aluminum alloy panel Steel sheet

Hammering

Mallet or plastic
hammer

Sheet metal
hammer

Washer
welding

Not possible

Possible

Gas welding Not good workability

but possible

Possible

Spot welding Not possible

Possible

MIG welding Possible by a welding

machine for aluminum
and argon gas

Possible by
a general
welding
machine and
CO

gas

Material

Melting point

Aluminum

475 to 660

°C (887 to 1220 °F)

Steel sheet

1500 to 2500

°C (2732 to 4532 °F)

ALUMINUM PANEL

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9. General tools and sanding tools shall not be shared for both

aluminum alloy and steel panels. (Iron powder remaining on
the surface may cause electric corrosion with a different
type of metal).

10.During MIG welding, protect the vicinity because the

spatters are hard to see and spread father than expected.

Correction of uneven surface

Basically, the same as the steel panel. However, give a consid-
eration to the aluminum alloy characteristics.
1. Repair of sheet metal

(1) Heat with a burner.

CAUTION

• Heat-up the panel until you feel heat with a keplar work

glove on the reverse side of the panel.

• Keep moving the burner evenly to prevent heat from

concentrating in one point.

(2) Because hammering may stretch the panel, use a mallet

or plastic hammer.

CAUTION

Minimize the stretch and hardening, and give no hammer
dent.

2. Distortion check: Grind the surface with #80 to #120-grit

sandpaper and then check for distortion.

AB202119AB

AB202120AB

AB202113

ALUMINUM PANEL

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3. Straightening: Remove distortion by the draw correction

procedure with a flattening hammer and a burner.

CAUTION

• The heating temperature should be approximately

250

°C (482°F).

• Pay particular attention to heating, because it is melted

without discolouration by heat.

• Cover the vicinity of the area to be heated with a wet

rag or the like to prevent temperature rise and influence
of heat (distortion).

• Do not use a draw hammer for steel sheets because it

may cause the panel crack.

4. Sanding: Grind the surface with a disk sander or a

double-action sander.

• Disk sander: #100 to #120

• Double-action sander: #150 to #180

CAUTION

Aluminum plates are softer than steel sheets, therefore
select an appropriate abrasive to prevent the surface from
deeply scratched. The heating temperature should be
approximately 250

°C (482°F).

Correction of cuts and cracks

If cuts, cracks, or holes occur in a steel sheet panel, MIG weld-
ing with CO

is used for repair. However, for an aluminum

panel, use MIG or TIG welding with argon gas (inert gas) as
shielding gas for repair.

DEGREE OF DISTORTION CAUSED BY WELDING

Gas welding (a large amount of distortion) TIG welding MIG
welding (a small amount of welding). This manual explains the
operation procedure of MIG welding which causes a small
amount of distortion by welding heat.

Operation procedure of MIG welding

CAUTION

• Be careful to avoid excessive stretch of or damage to

the panel.

• Minimize the gap of the butt joint.

1. Correct the damaged area by hammering lightly while

heating it. If any area is stretched by hammering, grind it off
with a pneumatic saw.

AB202116AB

AB202109

AB302173

AB202121AB

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