Abstract: An abrasion-resistant steel consists essentially of 0.05 to 0.45 wt. % C, 0.1 to 1 wt. % Si, 0.1 to 2 wt. % Mn, 0.05 to 2 wt. % Nb and the balance being Fe and inevitable impurities, the steel includes at least 200 of precipitates of 15 .mu.m or more in particle size per 1 mm.sup.2 and the precipitates contains Nb.In addition to the above basic elements, at least one element selected from the group consisting of 0.1 to 2 wt. % Cu, 0.1 to 10 wt. % Ni, 0.1 to 3 wt. % Cr, 0.1 to 3 wt. % Mo and 0.0003 to 0.01 wt. % B or at least one element selected from the group consisting of 0.003 to 0.05 wt. % Ti and 0.01 to 1 wt. % V is added to steel.

Abstract: An abrasion-resistant steel having excellent surface property consists essentially of 0.1 to 0.45 wt. % C, 0.1 to 1 wt. % Si, 0.1 to 2 wt. % Mn, 0.04 wt. % or less P, 0.04 wt. % or less S, 0.1 to 1 wt. % Ti, 0.0015 to 0.01 wt. % N, and the balance being Fe and inevitable impurities, the steel including at least 400 TiC precipitates of 0.5 .mu.m or more in particle size per 1 mm.sup.2 and the steel having Ti* of 0.05 wt. % or more and less than 0.4 wt. % the Ti* being defined by the equations of Ti*=Ti(a)-[Ti], Ti(a)=Ti-{(48/14)N+(48/32)S}, log[Ti][C]=(-10580/T)+4.38, [Ti]=4.times.[C]+{Ti(a) -4.times.C}.A method for producing an abrasion-resistant steel having excellent surface property comprising the steps of: preparing a molten steel having the composition specified above; casting continuously the molten steel to produce slab, coarse particles of TiC being precipitated in the slab; hot-working the slab to produce a hot-rolled steel sheet at 1300.degree. C. or less; and quenching the hot-rolled steel sheet.

Abstract: An abrasion-resistant steel consists essentially of 0.05 to 0.45 wt. % C, 0.1 to 1 wt. % Si, 0.1 to 2 wt. % Mn, 0.05 to 1.5 wt. % Ti and the balance being Fe and inevitable impurities, the steel includes at least 200 of precipitates of 1 .mu.m or more in particle size per 1 mm.sup.2 and the precipitates contains Ti.In addition to the above basic elements, at least one element selected from the group consisting of 0.1 to 2 wt. % Cu, 0.1 to 10 wt. % Ni, 0.1 to 3 wt. % Cr, 0.1 to 3 wt. % Mo and 0.0003 to 0.01 wt. % B is added to steel or at least one element selected from the group consisting of 0.005 to 1 wt. % Nb and 0.01 to 1 wt. % V is added to steel.

Abstract: An abrasion resistant steel consisting essentially of 0.05 to 0.45 wt. % C, 0.1 to 1 wt. % Si, 0.1 to 2 wt. % Mn, 0.3 to 1.5 wt. % Ti, at most 0.005 wt. % N and the balance Fe as the basic elements contributing to the enhancement of the abrasion resistance property, without excessively increasing the hardness of the steel. In addition to the basic elements, at least one element selected from the group consisting of 0.1 to 2 wt. % Cu, 0.1 to 10 wt. % Ni, 0.1 to 3 wt. % Cr, 0.1 to 3 wt. % Mo and 0.0003 to 0.01 wt. % B may be added to enhance the quenching hardenability of the steel, and 0.01 to 0.5 wt. % V may be added to enhance the precipitation hardenability of the steel.

Abstract: A method for manufacturing a steel article having a high magnetic permeability and a low coercive force, comprising the steps of: heating a material consisting essentially of:carbon: from 0.02 to 0.08 wt. %,manganese: from 0.05 to 0.49 wt. %, andthe balance being iron and incidental impurities, to a temperature of at lest 1,000.degree. C.; then hot-working the thus heated material at a finishing temperature of at least 1,000.degree. C. to prepare a steel article and then cooling the thus prepared steel article to a temperature of up to 500.degree. C. at a cooling rate of up to 0.5.degree. C./second; thereby causing crystal grains of the steel article to grow to a grain size of at least 50 .mu.m to impart a high magnetic permeability and a low coercive force to the steel article.

Abstract: An iron-based shape-memory alloy excellent in a shape-memory property, a corrosion resistance and a high-temperature oxidation resistance, consisting essentially of:chromium: from 5.0 to 20.0 wt. %,silicon: from 2.0 to 8.0 wt. %,at least one element selected from the group consisting of:manganese: from 0.1 to 14.8 wt. %,nickel: from 0.1 to 20.0 wt. %,cobalt: from 0.1 to 30.0 wt. %,copper: from 0.1 to 3.0 wt. %, andnitrogen: from 0.001 to 0.400 wt. %,whereNi+0.5 Mn+0.4 Co+0.06 Cu+0.002 N.gtoreq.0.67 (Cr+1.2 Si)-3,and the balance being iron and incidental impurities.

Abstract: An iron-based shape-memory alloy excellent in a shape-memory property and a corrosion resistance, consisting essentially of:______________________________________ chromium: from 0.1 to 5.0 wt. %, silicon: from 2.0 to 8.0 wt. %, manganese: from 1.0 to 14.8 wt. %, at least one element selected from the group consisting of: nickel: from 0.1 to 20.0 wt. %, cobalt: from 0.1 to 30.0 wt. %, copper: from 0.1 to 3.0 wt. %, and nitrogen: from 0.001 to 0.400 wt. %, where, Ni + 0.5 Mn + 0.4 Co + 0.06 Cu + 0.002 N .gtoreq. 0.67 (Cr + 1.2 Si), and the balance being iron and incidental impurities.