What is the difference between Armox 500T and Armox 600T?

Armour plate is selected on threat level first and fabricability second.

500T (about 480 to 540 HBW) is the general purpose protection plate: vehicle hulls and add-on kits, cash-in-transit bodies, secure rooms, ballistic doors and shelters. It bends with a generous radius across the rolling direction and welds with austenitic stainless or low-hydrogen consumables, with preheat by thickness.

600T (about 570 to 640 HBW) buys protection at lower areal weight — meaningful when payload or mobility is the constraint. The trade-off is fabricability: tighter bend limits, more careful cutting, and welding that must avoid the hardest zones altogether where possible.

For both: never stress relieve, keep heat input low, and design the joint so the weld is not in the ballistic path. Thermal cutting leaves a heat affected edge — allow for it in the layout, or ask for waterjet.

Protection levels should be stated as the standard and threat you must defeat (STANAG 4569 level, NIJ level, or VPAM class) rather than a plate thickness. The plate thickness follows from the threat, the obliquity and the standoff, and the mill ballistic certificate is what the end client will ask to see.