Info Favorites Register Log in
myArmoury.com Discussion Forums

Forum index Memberlist Usergroups Spotlight Topics Search
Forum Index > Historical Arms Talk > the science behind plate armour Reply to topic
This is a standard topic  
Author Message
Nathan Quarantillo




Location: Eastern Panhandle WV, USA
Joined: 14 Aug 2009

Posts: 279

PostPosted: Mon 28 Sep, 2009 11:34 am    Post subject: the science behind plate armour         Reply with quote

Ive always wondered what allowed a breastplate to have the amazing properties of protection it gives. the science behind it, what allows it to go were the same thickness sheet steel will fail. how it even seems to negate impacts as much as cutting edges. how did it evolve these features? how did they work? all help is appreciated! -thanks!
"Id rather be historically accurate than politically correct"
View user's profile Send private message
Dan P




Location: Massachusetts, USA
Joined: 28 Jun 2007

Posts: 208

PostPosted: Mon 28 Sep, 2009 12:15 pm    Post subject:         Reply with quote

Both armor plate and sword blades were hardened and tempered for their purposes. A properly hardened sword blade will tend to go through softer things such as sheet steel, but be turned aside by harder steel armor. Also most armor tends to have rounded and curved surfaces rather than large flat areas. This is so any strike by the point of a weapon will tend to hit at a glancing angle and be deflected instead of at a right angle that would maximize piercing potential.
View user's profile Send private message
Luke Zechman




Location: Lock Haven Pennsylvania
Joined: 18 Jan 2009

Posts: 278

PostPosted: Mon 28 Sep, 2009 12:24 pm    Post subject:         Reply with quote

I am no expert but I would have to say one of the biggest contributing factors would be shape. For example... The rolled edges, creases in the surface will all add rigidity. Think of a potato chip with ridges... makes for a stronger scooper of dips. In addition to the contours on the surface of plate mails, they had also been designed to distribute the force of an impact, much the opposite as many of the weapons that are more effective against plate that tend to concentrate force. Think of the spike side of a typical warhammer, one of those weapons effective against plate. Shape of plate mail was also designed to make it hard to get a square hit. Instead the curved surfaces would turn a typically good square hit in to a glancing blow. I am simply applying my understanding of physics here. I am not at all educated on the technology of plate mail.
I am sure that there are other factors which would contribute to plate mails durability which might include treatment to the metal itself, which I know nothing about... I am sure someone will chime in with some actual knowledge on the subject.
View user's profile Send private message
Allan Senefelder
Industry Professional



Location: Upstate NY
Joined: 18 Oct 2003

Posts: 1,563

PostPosted: Mon 28 Sep, 2009 12:40 pm    Post subject:         Reply with quote

Quote:
Both armor plate and sword blades were hardened and tempered for their purposes


Some plate armour was, usually finer examples.
View user's profile Send private message Visit poster's website
M. Eversberg II




Location: California, Maryland, USA
Joined: 07 Sep 2006
Reading list: 3 books

Spotlight topics: 1
Posts: 1,435

PostPosted: Tue 29 Sep, 2009 5:13 am    Post subject:         Reply with quote

Curvature contributes the best against most attacks. Much of your force of impact will bleed off if you don't strike at 90 or near 90 degrees.

M.

This space for rent or lease.
View user's profile Send private message AIM Address Yahoo Messenger MSN Messenger ICQ Number
Matthew Fedele




Location: Auburn, NY USA
Joined: 21 Jul 2005

Posts: 64

PostPosted: Tue 29 Sep, 2009 5:56 am    Post subject:         Reply with quote

There is a good book out there on the subject although hard to find: The Royal Armoury at Greenwich 1515-1649: A History of Its Technology (Royal Armouries Monograph)

It was a metallurgical analysis of period armour and the conclusion was that even when the quality of the steel was poor attempts were still made at hardening. The hardening process shows up under the microscope and they can tell when iron was quenched hot. Another interesting tid bit from that book was that a single sheet of steel could range from wrought iron to high carbon steel. The carbon was "streaky" through the piece as they didn't have the modern homogeneous steels we have today.

Even a wrought iron breastplate is going to protect you from a cutting edge however, it's just not the right tool for that job.

Cheers,
Matt
View user's profile Send private message Visit poster's website
William Knight




Location: Mid atlantic, US
Joined: 02 Oct 2005

Posts: 133

PostPosted: Tue 29 Sep, 2009 6:18 am    Post subject:         Reply with quote

Go read "The Knight and the Blast Furnace" by Allan Williams. University libraries near you may have a copy--buying it is rather expensive.

I need to get to work, but I'll post some general stuff later.

-Will
View user's profile Send private message
Allan Senefelder
Industry Professional



Location: Upstate NY
Joined: 18 Oct 2003

Posts: 1,563

PostPosted: Tue 29 Sep, 2009 6:42 am    Post subject:         Reply with quote

Quote:
There is a good book out there on the subject although hard to find: The Royal Armoury at Greenwich 1515-1649: A History of Its Technology (Royal Armouries Monograph)

It was a metallurgical analysis of period armour and the conclusion was that even when the quality of the steel was poor attempts were still made at hardening. The hardening process shows up under the microscope and they can tell when iron was quenched hot. Another interesting tid bit from that book was that a single sheet of steel could range from wrought iron to high carbon steel. The carbon was "streaky" through the piece as they didn't have the modern homogeneous steels we have today.

Even a wrought iron breastplate is going to protect you from a cutting edge however, it's just not the right tool for that job.


The Armor from Medieval Rhodes also demonstrates this. Microscopic metalurgical analysis was done of 20 or so pieces ranging from the mid 15th century to the early 16th and revealed that where attempts to harden the metal were tried, it was being tried on eveything from iron to low coarbon steel to higher carbon ( temperable ) steel, seeming to indicate that there was an understanding of " how " to do it but not necessarily " why " it worked.

The Greenwich book is kind of a Cliff Notes of " The Knight and the Blast Furnace " which is a pretty definitve work on the subject. The Greenwich book is also by Alan Williams.
View user's profile Send private message Visit poster's website
Justin King
Industry Professional



Location: flagstaff,arizona
Joined: 12 Apr 2004
Reading list: 20 books

Posts: 551

PostPosted: Tue 29 Sep, 2009 7:11 am    Post subject:         Reply with quote

I think it is interesting that they attempted to harden low-carbon or wrought iron, these materials would generally be harder and springier if cold-worked to some degree and left in that state, than they would be after heating and quenching.
I wonder if perhaps these pieces which were quenched but do not contain enough carbon to harden effectively, may be pieces which they attempted to carburize, but unsuccessfully?

To look at it from another angle, though, hardness does not directly equal toughness or resilience, so in considering just the hardness we are perhaps barking up the wrong tree, their criteria in period may have been quite different from ours. Interesting stuff.


Last edited by Justin King on Tue 29 Sep, 2009 7:21 pm; edited 1 time in total
View user's profile Send private message
James Arlen Gillaspie
Industry Professional



Location: upstate NY
Joined: 10 Nov 2005

Posts: 555

PostPosted: Tue 29 Sep, 2009 11:41 am    Post subject:         Reply with quote

The old irons and steels don't like work hardening. It makes them much more brittle than it does modern steels.
jamesarlen.com
View user's profile Send private message Visit poster's website
Matthew Fedele




Location: Auburn, NY USA
Joined: 21 Jul 2005

Posts: 64

PostPosted: Tue 29 Sep, 2009 7:02 pm    Post subject:         Reply with quote

Thanks, I added "The Knight and the Blast Furnace" to my amazon wishlist which continues to grow unlike my bank account. It does sound like it mirrors the Greenwich findings.

Justin, It's been a few years since I've read that, but I don't believe they found evidence of any case hardening. I also found it curious that they attempted hardening low carbon steels, but really without hitting it with a grinding wheel and observing the sparks I don't think I could tell the difference between annealed high carbon and low carbon steel especially when it was mixed in the same piece of metal. There's probably other people here with more experience with that though, I'm used to modern steels. Finding wrought iron and non industrial-era steel now days is tough and if I did find it I'd save it for a special project.

Cheers!
Matt
View user's profile Send private message Visit poster's website
Helge B.





Joined: 06 Mar 2008

Posts: 73

PostPosted: Tue 29 Sep, 2009 11:08 pm    Post subject:         Reply with quote

I would like to add the question:

What does it need to make plate armour shot-proof beside making it simply thicker?

Was there any armour which really could withstand a point blank shot of a heavy musket?
View user's profile Send private message
Dan Howard




Location: Maitland, NSW, Australia
Joined: 08 Dec 2004

Spotlight topics: 2
Posts: 3,394

PostPosted: Wed 30 Sep, 2009 3:13 pm    Post subject:         Reply with quote

DUPLEX: It consists of a plate of softer iron riveted or welded to a plate of harder steel.

There are also recipes for different heat treatments for shot proof plate but it would have been difficult to do these accurately enough with the technoloogy available.

Read the RA's journal Arms and Armor, Vol. 2, No. 1 "Duplex Armour: an unrecognised mode of construction." pp.5-26
View user's profile Send private message
William Knight




Location: Mid atlantic, US
Joined: 02 Oct 2005

Posts: 133

PostPosted: Wed 30 Sep, 2009 9:37 pm    Post subject:         Reply with quote

Helge B. wrote:


Was there any armour which really could withstand a point blank shot of a heavy musket?


No.

One Elizabethan authority says that a musket could kill a man in proof armour at 100 yards and I've never seen this contradicted on the low (range) side. Even if there are some sources that I'm missing, there's an awful lot of ground between 100 yards (engagement range, I think) and point-blank.

As to other methods of bullet-proofing armour, Williams is pretty convinced in The Knight and the Blast Furnace that heat treating was also valued as a way to accomplish this, at least in Germany and later, England.

-Wilhelm
View user's profile Send private message
Dan Howard




Location: Maitland, NSW, Australia
Joined: 08 Dec 2004

Spotlight topics: 2
Posts: 3,394

PostPosted: Thu 01 Oct, 2009 3:07 am    Post subject:         Reply with quote

At the Battle of Roundway Down Sir Arthur Hasselrigg was unharmed after bing hit by three point blank shots, but it isn't clear what the weapons were.

King Charles quipped "had he been vitualled as well as fortified he might have endured a siege of seven years"
View user's profile Send private message
Daniel Staberg




Location: Gothenburg/Sweden
Joined: 30 Apr 2005
Likes: 2 pages
Reading list: 2 books

Posts: 567

PostPosted: Wed 07 Oct, 2009 2:32 am    Post subject:         Reply with quote

Dan Howard wrote:
At the Battle of Roundway Down Sir Arthur Hasselrigg was unharmed after bing hit by three point blank shots, but it isn't clear what the weapons were.

King Charles quipped "had he been vitualled as well as fortified he might have endured a siege of seven years"

As Atkyns eyewitness account makes clear the shots were all from pistols, 4 shots in total, two from Atkyns, one from 'Mr Holmes' and the fourth from Captain Buck. Not to mention that these gentlemen were hacking and thrusting at Haselrig with sword and hanger. A very revealing account of just how hard it was to kill a man in high quality cuirassier armour.
http://www.english-heritage.org.uk/upload/pdf/Roundway.pdf
View user's profile Send private message
Dan Howard




Location: Maitland, NSW, Australia
Joined: 08 Dec 2004

Spotlight topics: 2
Posts: 3,394

PostPosted: Wed 07 Oct, 2009 4:34 am    Post subject:         Reply with quote

Thanks Daniel. I hadn't read Atkyns.
View user's profile Send private message


Display posts from previous:   
Forum Index > Historical Arms Talk > the science behind plate armour
Page 1 of 1 Reply to topic
All times are GMT - 8 Hours

View previous topic :: View next topic
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum






All contents © Copyright 2003-2020 myArmoury.com — All rights reserved
Discussion forums powered by phpBB © The phpBB Group
Switch to the Basic Low-bandwidth Version of the forum