"Why the Panther’s Armor was Worse than You Think" Topic

"Today, we will look at the major flaw of the German Panther tank, and look at the faulty metals used on German tanks during the Second World War which led to a large number suffering extreme cracking and spalling after receiving hit. This is supported by the metallurgical tests undertaken by the British, American, and Canadians during the war…"

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Armand

Spalling is not a defect in the tank armor. It is a result of the ammo being fired. Even a round that does not penetrate can cause spalling.
The sloping Panther amour was better than the vertical armor of earlier tank designs.

I think that poor metals or bad welding could increase the spalling? And Germany was certainlyscrapping the bottom of the resource locker in 44 and 45.

It is not poor metal. Armor is case harden to produce a high surface hardness to resist the penetration of the initial hit at contact. Below the surface, the armor is softer and can absorb the hit.

Only the case hardened surface will spall, or fracture, as harder part does not have the fracture toughness like the core has.

Depending on the angle of the armor at impact will determine whether the the the armor will fracture at the surface or simply force a glance.

The case hardening of armor was the primary method used on all tanks as well as ship armor.

Kim

The article does a wonderful job of explaining why the metal was "poor." Mainly the final alloy was poor and the methods used for heat treating and such were not done properly, especially in 1944-5. The aspect of heterogeneous armor not resisting penetration as well when angled is one I'm not familiar with and can't comment on it.

Very interesting article.

Thanks…

Armand

It is possible to overestimate the inherent brilliance of the Germans:

Ha!…

Armand

From what I've read, the quality of German armor fell off as it lost control of areas that provided it with key ingredients for the alloy used. So the Allies' view of it would depend on WHEN the tests were made.

KRY: I believe the phrase is face-hardened. Face-hardened armor worked great against the kind of AT ammo the Russians used -- not so well against American and British ammo.

By the way…

Safety brief: Don't hide a WWII-era Panther tank in your basement

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Armand

German face-hardened armor (also called Krupp Cemented/carburized Armor) worked well against uncapped AP rounds which is what most guns were using at the start of WWII forcing the round to shatter. However, face-hardened armor was more easily pierced by capped APC rounds because the cap shattered the face of the armor. This is probably why the Germans stopped using FHA armor late in the war when the Allies were all using capped AP rounds.

However, if the nose of the AP round was more brittle than the armor the round could shatter or break up while penetrating. It gets complicated.

Another factor overlooked in games is that to be most effective the round must over-penetrate the armor (by about 20%) to fully enter the fighting compartment and cause damage. This is especially true with APHE shells whose bursting charge is at the tail of the round.

If the round penetrated 3" into 3" of armor the round will most likely be stuck or broken up with the only interior damage being some spalling. If brittle enough, the armor could also crack.

The bottom line is that armor penetration is not an all-or-nothing result. Non-penetrating spalling can result in enough interior damage to force the crew to bail out. The more brittle the interior armor is, the greater the spalling.

FYI: Cast armor is about 10% less effective than RHA and I don't think it could be face-hardened.

The book "WWII Ballistics and Armor" has some good info on how this all works.

Wolfhag

Thanks- that's interesting stuff. One game that I always thought captured some of the complexity of the innovative process (at least in terms of written rules) you described was the old "Advanced Squad Leader," but it concentrated on the increases in gun size and muzzle velocity, and ammunition types, while ignoring the protective half of the model (IIRC- it's been twenty years since I saw an ASL book).