Abstract
Phenomena appearing during sintering process of an iron-1.0wt%tin mixed powders compact were investigated in comparsion with those of the iron powder compact. The results obtained are as follows;
When the iron-tin mixed powders compact is being heated, tin powder particles become liquid at the melting-point of tin, 505 K (232°C). The tin-liquid penetrates into capillaries between iron powder particles above about 673 K (400°C) and with the rising of temperature up to about 1173 K (900°C), the tin-liquid forms various tin-iron intermetallic compounds; θ, η, ε and ζ by the dissolution with a little of iron powder and also, these compounds produce their respective transient liquid phases by the decomposition of themselves. The above phenomena make the compact have a lower strength as well as more expansion in comparison with those of iron powder compact.
When the temperature is above about 1273 K (1000°C) however, all the intermetallic compounds become α phase iron-tin solid-solution having higher self-diffusion coefficient than the γ phase. The above phenomena make the compact have a higher strength as well as more shrinkage in comparsion with those of iron powder compact at the sintering temperature of about 1423 K (1150°C).