... D3 Alloy Steel 1, Round/Plate/Square bar in ful size 2, Hardness: HRC=60, HBS<=370 ... 3, ISO 9001 2008 certificated D3 Alloy Steel Round Bar1, Round/Plate/Square bar ... 5800mmSteel plateThicknessWidthLength20-400mm50-800mm2000mm-5800mm 2, Delivery Condition: 1) Hot rolled , black,2) Hardness: HRC=60~623 ... reference only): CSiMnCrNiCuEqual or less than2.00~2.30≤0.40,≤0.40,11.50~ ...