Britain’s Ministry of Defence (MOD) Tuesday acknowledged that developing protective vehicle armor with holes in it may not seem the most obvious way to increase protection for British troops on operations but said that’s just what its scientists are doing.
“You shouldn’t think of them as holes, you should think of them as edges,” Peter Brown, a scientist at the Defence Science and Technology Laboratory (DSTL), said. “When a bullet hits an edge, it gets deflected, and turns from a sharp projectile into a blunt fragment, which is much easier to stop.”
Since 2000 DSTL at Porton Down in Wiltshire has worked in collaboration with Cambridge University and QinetiQ to develop Super Bainite, a unique ultra-hard armor material.
The introduction of holes also reduces weight, Brown said, and doubles the ballistic performance, making perforated Super Bainite steel armor ballistically very efficient.
Invented, designed and manufactured in the UK, Super Bainite is experimental high performance armor steel developed to save the lives of UK Armed Forces and the armor has performed well in ballistic testing at the MOD’s firing ranges.
Unlike conventional steels, the composition of Super Bainite was derived from first principles using thermodynamic modeling techniques. This allowed its processing, properties and cost to be optimized in months rather than years.
It has been know since the 1930s that certain heat treatments alter the fine-scale structure of steel creating a ‘phase’ called bainite, but in collaboration with steelmaker Corus, DSTL scientists have developed a new manufacturing process, which allows the alloy to be produced quickly and cost effectively.
“Whilst other armor steels need to be quenched and tempered, Super Bainite develops its properties by a low temperature mechanism called isothermal hardening, the MOD said. “This enables ultra-high levels of hardness to be achieved without having to use expensive alloying additions.”
Isothermal hardening involves the steel being heated to 1,000C, cooled to about 200C, and then held at this temperature for a period of time before cooling to room temperature. This is how the Super Bainite develops its exceptional strength.
Traditionally, MOD said it has utilized offshore suppliers to fulfill its specialist armor requirements. However, following the successful industrial production trials, directed by DSTL in partnership with Corus and Bodycote, MOD said the UK is now well placed to develop a secure onshore supply of specialist, high hardness steel armor.
“Due to the unique process by which we have developed this new armor, Super Bainite is able to match the ballistic performance of the best off-shore armor steels at reduced cost,” Brown added.