I remember reading about the armored cars made by the Brazilion Engesa company.  They had the EE-9 Cascavel armored car, anf the EE-11 Urutu armored personnel carrier (IIRC).

What I was reading made prominent mention of it's unique armor which uses dual hardness steel.  

They never mentioned of the softer steel was on the inside or outside.  I was wondering which it is, and what the benefit is to having dual hardness steel.  I would think that hardened steel all through would be better, but apparently this is not the case.

Anyone have any answers?


-K

Oh come on, someones gotta know!  


-K

engesa.com.br
find someone that speaks Portugese
most of the site is under construction.
so you have time....
Midwinter

My girlfriend's brother is a Swat officer in BOPE Rio de Janeiro, they have an armored car that they use to assault the favelas but it was patched up for bulletholes, send me an email I will try to send you some pics....don't know it its the same make and model...

My guess is that the softer steel would be on the outside to help absorbe any energy from a blast or projectile.

Engesa site may be under construction for a while. My understanding is that they went out of business a few years ago.

NTM

The Cascavel is protected by an unusual dual-hardness aromr configuration.  It consists of an outer layer of hard steel and an inner layer of roll-bonded, heat treated soft steel.  I assume this is to reduce spalling.  Even if a large round bounces off, or even in the case of a penetration, the softer steel will spall less.  Fragments from the hard outer layer caused by the penetration would be held by the softer inner layer, which would tend to bend rather than break-off.  So more often, you'd get a jagged hole, but all the armor still attatched to the surrounding armor.  If the armor were all hard, you'd get a hole, and alot of fragments and splinters from the armor flying around inside as well as the projectile that did the penetration.  This is just my assumption, but it's one of the reasons aluminum is used under steel in many vehicles.  I'd say in this case, the dual-hardness allows the use of cheaper steel, and probably gives better protection than alloy/steel combinations.

The suspension is basically what ENGESA used on their 6x6 tactical trucks, so it has good cross-country perfromance, and can move pretty quick on a road too.  It uses a Detroit Diesel 6 cyl, 212HP powerpack to move the Cascavel up to 62MPH (100KPH), and economical enough to drive 550 miles (880KM), it does pretty good on the roads and hills of South America overall.  It is not amphibious, but can ford 1 meter without preperation.  It's supposedly simple and fairly easy to work on, but not really built for higher levels of maintenance out in the field.  

It's armed with a Brazillian made version of the 90mm Cockerill gun and is equipped with a laser rangefinder, and the usual fire control stuff.  The usual 7.62/.50 Brownings and smoke launchers is also fitted.  

There's no NBC system, or air conditioning, and some have Benz diesel engines.  The Urutu is basically an APC version of the armored car, and shares most components.  It can be equipped with Milan AT missles, and the usual other stuff just about anyone can tack onto any APC.  

They're very successful designs that have done quite well for Brazil's arms industry.

The armored Mercedes cars I was riding in in Sao Paulo recently were armored in the US conventional way - replacement external skin, ballistic panels inside the cavities, glass replaced with polycarbonate or whatever it is that they use. I saw only armored Mercedes Benz and a couple of Lincolns.

NO AC!!! screw that would rather take the bullets

Quoted: Face hardened steel is old technology, they used it on ships and armor vehicles for many years… the very hard face breaks up projectile, but that hard face is brittle, the soft back supports it and stops the plate cracking. ANdy

High tech.....................for WWII.