70Mn2 alloy steel grinding rod with excellent mechanical properties and long service life, as well as preparation method thereof

The invention discloses a 70Mn2 alloy steel grinding rod with excellent mechanical properties and a long service life, as well as a preparation method thereof. The alloy steel grinding rod comprises the following chemical components: 0.58 to 0.74 percent of C (carbon), 0.25 to 0.35 percent of Si (silicon), 1.40 to 1.70 percent of Mn (manganese), not more than 0.025 percent of S (sulfur), not more than 0.035 percent of P (phosphorus), and the balance of Fe (ferrum) and unavoidable impurities. The preparation method of the alloy steel grinding rod comprises the procedures of top-bottom blowing in an LD (Linz-Donawitz) converter, deoxidation alloying, molten steel refining in an LF (ladle furnace), molten steel pouring, billet heating, billet rolling and rolled steel finishing, so as to obtain the target, i.e., the 70Mn2 alloy steel grinding rod. The preparation method has the characteristics of low production cost, as well as high process suitability and equipment universality; the manufactured alloy steel grinding rod has the remarkable advantages of high surface hardness (29 HRC (Rockwell hardness) to 36 HRC), high abrasion resistance, excellent bending-resistant performance, long service life, high easiness in replacement and the like, and can be used not only as a grinding medium material, but also in the fields such as superfine crushing of metallic minerals, fine grinding of fed pellets, processing of fine chemical materials, as well as comprehensive utilization of steel slags, mineral slags and other waste slags.