Rebar is the common name for hot rolled ribbed steel bars. The grade of ordinary hot-rolled steel bar is composed of HRB and the minimum yield point of the grade. H, R, and B are the first letters of the three words Hotrolled, Ribbed, and Bars respectively. Hot-rolled ribbed steel bars are divided into three grades: Grade II HRB335 (the old grade is 20MnSi), Grade III HRB400 (the old grades are 20MnSiV, 20MnSiNb, 20Mnti), and Grade IV HRB500.
