A steel material is disclosed. The steel material includes components in the following mass percentages: 14% to 20% of nickel, 7.5% to 11% of cobalt, 4% to 7% of molybdenum, to 0.5% of rhenium and/or a rare earth element, less than or equal to 0.2% of manganese, less than or equal to 0.2% of silicon, less than or equal to 0.1% of carbon, less than or equal to of oxygen, iron, and inevitable impurities. The steel mechanical part is made of the steel material. The preparation method includes: mixing alloy powder and a binder to prepare feed particles; performing injection molding on the feed particles to obtain an injection green billet of the steel mechanical part; performing debinding and sintering on the injection green billet in sequence to obtain a sintered blank; and performing heat treatment on the sintered blank to obtain the steel mechanical part.

In some embodiments, a coating applied to steel reinforcement bar (e.g., steel rebar) that could considerably extend the lifetime of concrete structures by reducing steel rebar corrosion is disclosed. The coating includes a thin, passivating steel (e.g., stainless steel) layer that is applied to the outside of conventional steel rebar. The coating can be applied in-line through metal cold spray manufacturing, which is a high throughput coating technique that can be integrated into existing steel manufacturing plants. Furthermore, a novel, high performance ferritic steel with tailored resistance to corrosion from chlorides is described. The new ferritic steel is distinct from other commercial and experimental steels, and is better suited for coating low-cost steel structures like rebar. Multiple alloying elements including Cr, Al, and Si will each form protective oxides independently, increasing the total amount of protection and extending it over much wider ranges of pH and electrical potential.

In some embodiments, a coating applied to steel reinforcement bar (e.g., steel rebar) that could considerably extend the lifetime of concrete structures by reducing steel rebar corrosion is disclosed. The coating includes a thin, passivating steel (e.g., stainless steel) layer that is applied to the outside of conventional steel rebar. The coating can be applied in-line through metal cold spray manufacturing, which is a high throughput coating technique that can be integrated into existing steel manufacturing plants. Furthermore, a novel, high performance ferritic steel with tailored resistance to corrosion from chlorides is described. The new ferritic steel is distinct from other commercial and experimental steels, and is better suited for coating low-cost steel structures like rebar. Multiple alloying elements including Cr, Al, and Si will each form protective oxides independently, increasing the total amount of protection and extending it over much wider ranges of pH and electrical potential.

In some embodiments, a coating applied to steel reinforcement bar (e.g., steel rebar) that could considerably extend the lifetime of concrete structures by reducing steel rebar corrosion is disclosed. The coating includes a thin, passivating steel (e.g., stainless steel) layer that is applied to the outside of conventional steel rebar. The coating can be applied in-line through metal cold spray manufacturing, which is a high throughput coating technique that can be integrated into existing steel manufacturing plants. Furthermore, a novel, high performance ferritic steel with tailored resistance to corrosion from chlorides is described. The new ferritic steel is distinct from other commercial and experimental steels, and is better suited for coating low-cost steel structures like rebar. Multiple alloying elements including Cr, Al, and Si will each form protective oxides independently, increasing the total amount of protection and extending it over much wider ranges of pH and electrical potential.

The present invention relates in a first aspect to an iron-based alloy powder containing non-spherical particles and at least 40% of the total amount of particles have a non-spherical shape. The alloy mandatorily comprises the elements Fe (iron), Cr (chrome) and Mo (molybdenum). Furthermore, the alloy may comprise further elements such as C (carbon), Ni (nickel), Nb (niobium) or Si (silicon). The present invention relates, according to a second aspect, to an iron-based alloy powder wherein the alloy comprises the elements Fe, Cr and Mo and the iron-based alloy powder is produced by an ultra-high liquid atomization process comprising at least two stages as defined below.

The present invention relates in a first aspect to an iron-based alloy powder containing non-spherical particles and at least 40% of the total amount of particles have a non-spherical shape. The alloy mandatorily comprises the elements Fe (iron), Cr (chrome) and Mo (molybdenum). Furthermore, the alloy may comprise further elements such as C (carbon), Ni (nickel), Nb (niobium) or Si (silicon). The present invention relates, according to a second aspect, to an iron-based alloy powder wherein the alloy comprises the elements Fe, Cr and Mo and the iron-based alloy powder is produced by an ultra-high liquid atomization process comprising at least two stages as defined below.

The present invention relates to an iron-based alloy powder containing non-spherical particles wherein the alloy comprises the elements Fe (iron), Cr (chrome) and Mo (molybdenum), and at least 40% of the total amount of particles have a non-spherical shape. In said iron-based alloy powder, Cr is present at 10.0 wt. % to 18.3 wt. %, Mo is present at 0.5 wt. % to 2.5 wt. %, C is present at 0 to 0.30 wt. %, Ni is present at 0 to 4.0 wt. %, Cu is present at 0 to 4.0 wt. %, Nb is present at 0 to 0.7 wt. %, Si is present at 0 to 0.7 wt. % and N is present at 0 to 0.20 wt. %, the balance up to 100 wt. % is Fe.

Provided are an ultra-clean rare earth steel and an occluded foreign substance modification control method, the steel includes 10-200 ppm of rare earth elements, 50% or more occluded foreign substances in the steel are dispersed into RE-oxygen-sulfide with the average equivalent diameter D.sub.mean ranging from 1-5 μm in a spherical shape or a substantially spherical shape or a granular shape; according to the method, at least 80%, preferably at least 90%, of Al2O3 occluded foreign substances in the steel are modified into RE-oxygen-sulfide, compared with steel with the same components without rare earth, the total amount of the occluded foreign substances in the steel is reduced by 18% or higher, the cracking probability caused by occluded foreign substances such as Al2O3 in traditional pure steel is reduced, the mechanical performance such as the fatigue life of the steel is remarkably improved.

Provided are an ultra-clean rare earth steel and an occluded foreign substance modification control method, the steel includes 10-200 ppm of rare earth elements, 50% or more occluded foreign substances in the steel are dispersed into RE-oxygen-sulfide with the average equivalent diameter D.sub.mean ranging from 1-5 μm in a spherical shape or a substantially spherical shape or a granular shape; according to the method, at least 80%, preferably at least 90%, of Al2O3 occluded foreign substances in the steel are modified into RE-oxygen-sulfide, compared with steel with the same components without rare earth, the total amount of the occluded foreign substances in the steel is reduced by 18% or higher, the cracking probability caused by occluded foreign substances such as Al2O3 in traditional pure steel is reduced, the mechanical performance such as the fatigue life of the steel is remarkably improved.

The invention provides method for making high coercivity magnetic materials based on FeNi alloys having a L1.sub.0 phase structure, tetratenite, and provides a system for accelerating production of these materials. The FeNi alloy is made by preparing a melt comprising Fe, Ni, and optionally one or more elements selected from the group consisting of Ti, V, Al, B, C, Mo, Ir, and Nb; cooling the melt and applying extensional stress and a magnetic field. This is followed by heating and cooling to form the L10 structure.