DEF STAN 02-770 (PART 1/ISSUE 2), DEFENCE STANDARD: REQUIREMENTS FOR THE WELDING AND FABRICATION OF HIGH STRENGTH STEELS (07 OCT 2005)., This part of the standard defines the general requirements and information on the fabrication, welding and inspection requirements for structures and associated components produced in High Strength Steels (HSS) i.e. Q1(N), Q2(N), QT35 and HY80. NOTE The welding and fabrication of QT28 and UXW is contained in Def Stan 02-706.