Abstract: A steel composition is provided and includes carbon of about 0.5 to 0.7 wt %; silicon of about 1.3 to 2.3 wt %; manganese of about 0.6 to 1.2%; chromium of about 0.6 to 1.2 wt %; molybdenum of about 0.1 to 0.5 wt %; nickel of about 0.05 to 0.8 wt %; vanadium of about 0.05 to 0.5 wt %; niobium of about 0.05 to 0.5 wt %; titanium of about 0.05 to 0.3 wt %; cobalt of about 0.01 to 3 wt %; zirconium of about 0.001 to 0.2 wt %; yttrium of about 0.01 to 1.5 wt %; copper of about 0.3% or less but greater than 0 wt %; aluminum of about 0.3% or less but greater than 0 wt %; nitrogen of about 0.03% or less but greater than 0 wt %; oxygen of about 0.003% or less but greater than 0 wt %. Additionally, a balance iron, based on the total weight is included.

Abstract: A steel composition is provided and includes carbon of about 0.5 to 0.7 wt %; silicon of about 1.3 to 2.3 wt %; manganese of about 0.6 to 1.2%; chromium of about 0.6 to 1.2 wt %; molybdenum of about 0.1 to 0.5 wt %; nickel of about 0.05 to 0.8 wt %; vanadium of about 0.05 to 0.5 wt %; niobium of about 0.05 to 0.5 wt %; titanium of about 0.05 to 0.3 wt %; cobalt of about 0.01 to 3 wt %; zirconium of about 0.001 to 0.2 wt %; yttrium of about 0.01 to 1.5 wt %; copper of about 0.3% or less but greater than 0 wt %; aluminum of about 0.3% or less but greater than 0 wt %; nitrogen of about 0.03% or less but greater than 0 wt %; oxygen of about 0.003% or less but greater than 0 wt %. Additionally, a balance iron, based on the total weight is included.

Abstract: A carburized steel composition of the present invention comprises: silicon (Si) in an amount of about 0.7 to 1.3 wt %, nickel (Ni) in an amount of about 0.15 to 0.5 wt %, chromium (Cr) in an amount of about 2.0 to 2.8 wt %, molybdenum (Mo) in an amount of about 0.15 to 0.5 wt %, vanadium (V) in an amount of about 0.02 to 0.1 wt % and nitrogen (N) in an amount of about 0.01 to 0.02 wt %, and iron (Fe) constituting the remaining balance of the carburized steel composition, all the wt % based on the total weight of the carburized steel composition.

Abstract: The present invention features a steel-base sintering alloy having a high wear-resistance for a valve seat of an engine. In preferred embodiments, the steel-base sintering alloy may include a chief element of Ferrum (Fe); and a powder-alloy which are composed of Carbon (C) of 0.6˜1.2 wt %, Nickel (Ni) of 1.0˜3.0 wt %, Cobalt (Co) of 15.0˜25.0 wt %, Chrome (Cr) of 3.0˜9.0 wt %, Molybdenum (Mo) of 8.0˜15.0 wt %, Tungsten (W) of 1.0˜4.0 wt %, Manganese (Mn) of 0.5˜2.0 wt %, and Calcium (Ca) of 0.1˜0.5 wt %.