An austenitic manganese steel microalloyed with nitrogen, vanadium and titanium used for castings such as mantles, bowls and jaws manufactured as wear components of crushers in the mining and aggregate industries, hammers used in scrap shredders, frogs and switches used in railway crossings and buckets and track shoes used in mining power shovels. These novel compositions exhibit a fine grain size having carbonitride precipitates that result in castings having a wear life 20-70% longer than prior art castings. The austenitic manganese steel includes, in weight percentages, the following: about 11.0% to 24.0% manganese, about 1.0% to 1.4% carbon, up to about 1% silicon, up to about 1.9% chromium, up to about 0.25% nickel, up to about 1.0% molybdenum, up to about 0.2% aluminum, up to about 0.25% copper, phosphorus and sulfur present as impurities in amounts of about 0.07% max and about 0.06% max. respectively, microalloying additions of titanium in the amounts of about 0.020-0.070%, optionally, microalloying additions of niobium in amounts from about 0.020-0.070%, microalloying additions of vanadium in amounts from about 0.020-0.070%, nitrogen in amounts from about 100 to 1000 ppm, and such that the total amount of the microalloying additions of titanium+niobium+vanadium+nitrogen is no less than about 0.05% and no greater than about 0.22%, the ratio of carbon to microalloying additions being in the range of about 10:1-25:1, and the balance of the alloy being essentially iron, the alloy being characterized by a substantial absence of zirconium and the presence of titanium carbonitride precipitates.