Temperature dependency of ballistic resistance of ARMOX 500

- F
- frank230458
  
  Contact options for registered users
posted
16 years ago

Sat, Jun 23, 2007 8:15 AM

Normally when people do testing of hard ballistic steel, like ARMOX, they test at an ambient temperature of about 20 degree celcius. Do different temperatures of the steel mean difference in the ballistic resistance of the steel? Especially it would be nice to have a graph or something showing the influence of the temperature in the range between say minus 20 degree celsius to about 100 degree celcius. For instance, a steel plate exposed to sun for some time in the desert would be heated up so soldiers could boil eggs on this. Is the level of protection on a heated up hard ballistic plate lesser or higher than a plate at 20 degrees celcius have. How much?

- B
- Brian Whatcott
  
  Contact options for registered users
Vote on answer
posted
16 years ago

Sat, Jun 23, 2007 1:47 PM

I can only offer the wooliest of generalities on this topic. Lacking any other data on steel performance at elevated temperatures, estimate that its strength is reduced by the fraction: ambient temp / melting temp. As to performance at cold temps, it was found that some steels suffered pronounced embrittlement at sub freezing temperatures - which started another hare running about the ultimate reasons for the Titanic disaster.....

Brian Whatcott Altus OK

- N
- N:dlzc D:aol T:com (dlzc)
  
  Contact options for registered users
Vote on answer
posted
16 years ago

Sat, Jun 23, 2007 5:11 PM

... both expressed in either Kelvin or Rankine

too much sulfur in the steel, something they did not routinely check for until the 1980s.

I would say that your factor described the puncture resistance of the plating, while

1 - ambient temp / melting temp ... might describe the tendency to shatter / or spall to become, in turn, shrapnel on the non-incident of the plating.

But I would expect no significant effect to occur unless the steel was at 800 degF for some period of time. The grain boundary migration would be glacial, taking aeons to years to have a significant effect on puncture strength.

More of concern to me (who is less knowledgeable than Brian), would be the effect of eggs on the metal itself. Consider the effect of hydrogen on most metals, cadmium on titanium, mercury on aluminum.

David A. Smith