A method for producing a composite magnetic body includes: pressure molding a metal magnetic material into a predetermined shape, the metal magnetic material being an Fe—Si-based metal magnetic material; performing a primary heat treatment of heating the metal magnetic material in an atmosphere with a first oxygen partial pressure to form an Si oxide coating film on a surface of the metal magnetic material; and performing a secondary heat treatment of heating the metal magnetic material that has undergone the primary heat treatment in an atmosphere with a second oxygen partial pressure, which is higher than the first oxygen partial pressure, to form an Fe oxide layer at least partially on a surface of the Si oxide coating film.

A method for producing a composite magnetic body includes: pressure molding a metal magnetic material into a predetermined shape, the metal magnetic material being an Fe—Si-based metal magnetic material; performing a primary heat treatment of heating the metal magnetic material in an atmosphere with a first oxygen partial pressure to form an Si oxide coating film on a surface of the metal magnetic material; and performing a secondary heat treatment of heating the metal magnetic material that has undergone the primary heat treatment in an atmosphere with a second oxygen partial pressure, which is higher than the first oxygen partial pressure, to form an Fe oxide layer at least partially on a surface of the Si oxide coating film.

A method of surface modification of a metal or metal alloy powder includes the steps of providing a metal or metal alloy powder including copper, gold, or silver and having an average diameter in the micron range; providing a powder having an alloying element to form an alloying element powder. The alloying element powder particles have an average diameter less than 10 micron and no more than half the average diameter of the metal or metal alloy powder particles; mixing the powders to form a mixed powder; heating the mixed powder in an atmosphere of reducing gas to a first temperature T1; after temperature T1 is reached, replacing the reducing gas atmosphere with an inert gas atmosphere and maintaining the temperature at a second temperature T2 for a predetermined time. The alloying element is capable of diffusing in the metal or metal alloy element at temperature T2.

A method of surface modification of a metal or metal alloy powder includes the steps of providing a metal or metal alloy powder including copper, gold, or silver and having an average diameter in the micron range; providing a powder having an alloying element to form an alloying element powder. The alloying element powder particles have an average diameter less than 10 micron and no more than half the average diameter of the metal or metal alloy powder particles; mixing the powders to form a mixed powder; heating the mixed powder in an atmosphere of reducing gas to a first temperature T1; after temperature T1 is reached, replacing the reducing gas atmosphere with an inert gas atmosphere and maintaining the temperature at a second temperature T2 for a predetermined time. The alloying element is capable of diffusing in the metal or metal alloy element at temperature T2.

A tungsten-base alloy material and a preparation method therefor. The preparation method comprises: 1) evenly grinding composite powder containing tungsten and zirconium oxide, and then performing annealing treatment at 700-1000° C. to obtain powder A; and 2) grinding and then compression moulding the powder A, and then performing liquid-phase sintering to obtain a tungsten-base alloy blank so as to obtain the tungsten-base alloy material.

A tungsten-base alloy material and a preparation method therefor. The preparation method comprises: 1) evenly grinding composite powder containing tungsten and zirconium oxide, and then performing annealing treatment at 700-1000° C. to obtain powder A; and 2) grinding and then compression moulding the powder A, and then performing liquid-phase sintering to obtain a tungsten-base alloy blank so as to obtain the tungsten-base alloy material.

A tungsten-base alloy material and a preparation method therefor. The preparation method comprises: 1) evenly grinding composite powder containing tungsten and zirconium oxide, and then performing annealing treatment at 700-1000° C. to obtain powder A; and 2) grinding and then compression moulding the powder A, and then performing liquid-phase sintering to obtain a tungsten-base alloy blank so as to obtain the tungsten-base alloy material.

The invention provides an iron-based metallic glass alloy powder including: Fe as the main component; a metalloid element group including Si, B, and C; a small amount of Mo to improve the degree-of-supercooling; and the addition of Cr and Ni to increase corrosion resistance, where the total amount of the metalloid element group, the amount of the degree-of-supercooling improvement element and the total amount of the elements to increase corrosion resistance are set within predetermined ranges.

The invention provides an iron-based metallic glass alloy powder including: Fe as the main component; a metalloid element group including Si, B, and C; a small amount of Mo to improve the degree-of-supercooling; and the addition of Cr and Ni to increase corrosion resistance, where the total amount of the metalloid element group, the amount of the degree-of-supercooling improvement element and the total amount of the elements to increase corrosion resistance are set within predetermined ranges.

A soft magnetic alloy including an internal area having a soft magnetic type alloy composition including Fe and Co, a Co concentrated area existing closer to a surface side than the internal area and having a higher Co concentration than in the internal area, and a SB concentrated area existing closer to the surface side than the Co concentrated area and having a higher concentration of at least one element selected from Si and B than in the internal area.