Provided are a SmFeN magnetic powder which is superior not only in water resistance and corrosion resistance but also in hot water resistance, and a method of preparing the powder. The present invention relates to a method of preparing a magnetic powder, comprising: plasma-treating a gas; surface-treating a SmFeN magnetic powder with the plasma-treated gas; and forming a coat layer on the surface of the surface-treated SmFeN magnetic powder.

Provided are a SmFeN magnetic powder which is superior not only in water resistance and corrosion resistance but also in hot water resistance, and a method of preparing the powder. The present invention relates to a method of preparing a magnetic powder, comprising: plasma-treating a gas; surface-treating a SmFeN magnetic powder with the plasma-treated gas; and forming a coat layer on the surface of the surface-treated SmFeN magnetic powder.

A method for coating a ceramic matrix composite substrate with an environmental barrier coating includes the steps of: treating a surface of a ceramic matrix composite substrate to adjust wettability of the surface; and applying an aqueous slurry-based environmental barrier coating to the surface. The treating step can be a plasma treatment to remove organic contaminants, and can also be a treatment to modify oxidative state of the surface. The treatment can produce a surface for treatment that is hydrophilic and has a contact angle with aqueous-slurry coating materials of less than 40 degrees.

A method for coating a ceramic matrix composite substrate with an environmental barrier coating includes the steps of: treating a surface of a ceramic matrix composite substrate to adjust wettability of the surface; and applying an aqueous slurry-based environmental barrier coating to the surface. The treating step can be a plasma treatment to remove organic contaminants, and can also be a treatment to modify oxidative state of the surface. The treatment can produce a surface for treatment that is hydrophilic and has a contact angle with aqueous-slurry coating materials of less than 40 degrees.

A method for producing a body obtained by processing a solid carbon-containing material, the method includes: preparing the solid carbon-containing material composed of a material having at least a surface containing solid carbon; forming a gas phase fluid containing at least one of an active gas or an active plasma which are active against the solid carbon; and processing the solid carbon-containing material by injecting the gas phase fluid onto at least a part of the surface of the solid carbon-containing material.

A method for producing a body obtained by processing a solid carbon-containing material, the method includes: preparing the solid carbon-containing material composed of a material having at least a surface containing solid carbon; forming a gas phase fluid containing at least one of an active gas or an active plasma which are active against the solid carbon; and processing the solid carbon-containing material by injecting the gas phase fluid onto at least a part of the surface of the solid carbon-containing material.

To form, on a ceramic member or a metal member, a thermal spray ceramic coating film which achieves both the quality of a ceramic coating film and gas barrier property, and with which a composite oxide having a melting point lower than the ambient temperature will not form when used as a coating film on a ceramic member or a metal member constituting a glass article manufacturing apparatus. A ceramic coating film-provided member comprising a ceramic member or a metal member and a thermal spray ceramic coating film formed on at least a part of the surface of the ceramic member or the metal member, wherein the thermal spray ceramic coating film contains Al.sub.2O.sub.3 and 12CaO.7Al.sub.2O.sub.3, and the weight ratio of CaO to Al.sub.2O.sub.3 (CaO/Al.sub.2O.sub.3) is more than 0.11 to 0.50.

Aspects include a method for treating a polycrystalline material, the method comprising: exposing a surface of the polycrystalline material to a plasma thereby changing the surface of the polycrystalline material from being characterized by a starting condition to being characterized by a treated condition; wherein: the surface comprises a plurality of crystallites each having the composition MB.sub.6, M being a metal element; the plasma comprises ions, the ions being characterized by an average ion flux selected from the range of 1.5 to 100 A/cm.sup.2 and an average ion energy that is less than a sputtering threshold energy; the starting condition of the surface is characterized by a first average work function and the treated condition of the surface is characterized by a second average work function; and the second average work function is less than the first average work function.

Aspects include a method for treating a polycrystalline material, the method comprising: exposing a surface of the polycrystalline material to a plasma thereby changing the surface of the polycrystalline material from being characterized by a starting condition to being characterized by a treated condition; wherein: the surface comprises a plurality of crystallites each having the composition MB.sub.6, M being a metal element; the plasma comprises ions, the ions being characterized by an average ion flux selected from the range of 1.5 to 100 A/cm.sup.2 and an average ion energy that is less than a sputtering threshold energy; the starting condition of the surface is characterized by a first average work function and the treated condition of the surface is characterized by a second average work function; and the second average work function is less than the first average work function.

Provided are a SmFeN magnetic powder which is superior not only in water resistance and corrosion resistance but also in hot water resistance, and a method of preparing the powder. The present invention relates to a method of preparing a magnetic powder, comprising: plasma-treating a gas; surface-treating a SmFeN magnetic powder with the plasma-treated gas; and forming a coat layer on the surface of the surface-treated SmFeN magnetic powder.