Electrical Conductivity and Microstructural Changes of Sintered Plain Carbon Steels Prepared from Different Base Powders

摘要

Electrical conductivity was used as a well known method to characterise microstructural changes and also the effective load bearing cross section in sintered materials. This physical measurement is applicable to use as a non-destructive way to predict the static and dynamic properties. In this research work, electrical conductivity and microstructural changes have been studied for a relatively wide sintering temperature range, from 700 to 1300°C. The studied materials were prepared from different water atomised and sponge iron powders. It has been found that after graphite dissolution and pearlite formation in the sintered microstructure, changes of the matrix microstructure are more effective towards the electrical conductivity than are changes of the load bearing cross section. In any case, the electrical conductivity, through Wiedemann-Franz's law, can be used to estimate the thermal conductivity which is otherwise tricky to measure.