Steel.

This is coolbert:

Once again from WIZARD through Harry at Sharkhunters:

"SPECIAL STEEL FOR OZ BOATS - Steel makers Bisalloy and BlueScope have inked a new contract with Naval Group Australia to produce up to 250 tons of specialized steel. As informed, the steel produced will be tested to determine whether it meets the specification for the pressure hull of the Royal Australian Navy’s new Future Submarines, which is an essential safety requirement. Minister for Defence Industry, the Hon Christopher Pyne MP, said over the past 12 months Naval Group has been working with Bisalloy and BlueScope to develop and qualify Australian steel to meet the specification required for the submarines. The Future Submarine Program (SEA1000), which encompasses a total of twelve submarines, is worth AUD 50 billion [$39 billion USD]. Australia’s fleet of twelve submarines will be built in a new Submarine Construction Yard in Adelaide. The construction of the first submarine is scheduled to commence in 2022-"

See recent blog entries as is germane:

http://militaryanalysis.blogspot.com/2018/02/shortfin.html

http://militaryanalysis.blogspot.com/2016/04/barracuda.html

coolbert.