30CrMnMoRE rolled steel

30CrMnMoRE code is 603 steel, the number in front is the logo of the successful year of trial production.
In 1960, the trial production of 601 cast steel and 603 rolled steel was successful, and won the first prize of the National Invention Award.

The first domestically produced nickel-free steel, code-named 603, which was finalized in 1963, was specially developed for five pairs of wheels. Its mechanical properties were compared with the American MIL-DTL-12560 (1976) standard Class 1/3 armor steel.

Among them, Class 3 steel is clearly mentioned as special steel and cannot be used to manufacture vehicles. There is a specified upper limit for the protection performance during acceptance.

603 steel, the nominal thickness is 80~100mm, the hardness is 341~269HB, the tensile strength is 1100~1200Mpa, and the lowest yield strength is 670Mpa.
American standard 1/3 type armor steel, nominal thickness 4 inches (~101mm), hardness 320~250HB (common target plate 260HB), tensile strength 800~870Mpa, yield strength about 650~710Mpa.

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