| 摘要 |
A method is provided for producing a diffusion alloyed powder consisting of an iron or iron-based core powder having particles of an alloying powder containing Cu and Ni bonded to the surface of the core particles, comprising providing a unitary alloying powder capable of forming particles of a Cu and Ni containing alloy, mixing the unitary alloying powder with the core powder, and heating the mixed powders in a non-oxidizing or reducing atmosphere to a temperature of 500-1000° C. during a period of 10-120 minutes to convert the alloying powder into a Cu and Ni containing alloy, so as to diffusion bond particles of the Cu and Ni alloy to the surface of the iron or iron-based core powder. The alloying powder may be a Cu and Ni alloy, oxide, carbonate or other suitable compound that on heating will form a Cu and Ni alloy. Preferably, the total content of Cu and Ni is at most 20 wt %, the particle size distribution of the Cu and Ni alloying powder is such that D50 is less than 15 μm, and the ratio Cu/Ni in wt % is between 9/1 and 3/1. The compacted and sintered parts produced from the diffusion alloyed iron-based powder present a minimum of variation of dimensional change from component to component. |
