Mitsubishi MOTORS Lancer Evolution 2008, Body Repair Manual

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ULTRA HIGH STRENGTH STEEL PLATE
TSB Revision
WELDED PANEL REPLACEMENT 3-2
ULTRA HIGH STRENGTH STEEL PLATE
M4030002800073
ADVANTAGES OF ULTRA HIGH
STRENGTH STEEL PLATE
The ultra high strength steel plate has the following
advantages as compared with conventional high
strength steel plate.
•
It has tensile strength approximately 1.7 times
higher than the conventional high strength steel
sheet.
•
It has a higher yielding point and yielding ratio
(yielding point/tensile strength).
These advantages allow thinner and lighter plates
and better fuel efficiency than the high strength steel
plate.
PRECAUTION UPON MAINTENANCE OF
ULTRA HIGH STRENGTH STEEL PLATE
•
Use a spot cutter for ultra high strength steel
plate to ensure that the spot-welded area is cut
off.
•
For the part in which the ultra high strength steel
plate is used, do not repair it by cutting and bond-
ing to avoid the reduction in strength by heat.
Instead, replace the whole assembly including
the part.
•
Be careful with rough extending work, because
the ultra high strength steel plate has higher ten-
sile strength and a higher yielding point than high
strength steel plate and general steel plate. Care-
less work will cause symptom such as over-pull-
ing and springback. Do not extend it completely
at a time. Do it gradually while removing the dis-
tortion by sheet metal processing with a hammer.
•
Plug welding of
φ
8 mm (0.31 inch) diameter plug
for repair ensures the strength equivalent to spot
welding for 2 steel sheets. For 3 sheets, weld 2
sheets each time instead of welding from one
side to give sufficient welding strength.