Control of reduction temperature in the process of secondary reduction of iron powder

According to the second reduction of thermodynamics and dynamics analysis, increasing temperature can make the reduction degree and reduction rate increases greatly For sponge iron powder, generally adopt the reduction temperature of 800 ~ 950, it is best to higher than 850 when fine reduction temperature more than 950, after the reduction of iron powder will burn into hard discus, produce too much coarse particle, making it broken cause difficulties;If it is forcibly broken, the compressibility of its comprehensive performance index drops sharply due to work hardening again, so that it can not be used.

For water atomized iron powder, due to its dense particles without pore, surface roughness is small, not easy to burn into pieces, so its fine reduction temperature is higher, generally for 1000 sometimes to low apparent density was higher formability of water atomized iron powder, such as Germany mannesmann WPL200 iron powder (apparent density is 2.6 g/cm3, combined the characteristics of reduced iron powder high formability), taken by the reduction temperature higher, up to 1050 ~ 1100, the fine particles reunited into a spongy coarse particle, thus achieve the goal of high formability.