抄録
Heterogeneous pores were often observed on lapped surface of cemented carbides with high Co content manufactured under some conditions. Therefore, the conditions and mechanism of the pore formation were mainly investigated and considered.
The results obtained were as follows: The amount and size of the pores increased with the increase of sintering temperature, cobalt content and particle size of WC. And these pores were distributed heterogeneously along certain curves on the lapped surface. Comparing the pore distribution with domain boundary of Co binder phase, the pores were confirmed to distribute at the domain boundary of cobalt phase. Especially, larger pores were generated near triple point of the domain boundary. Consequently, these heterogeneous pores were considered to be caused by solidification and shrinkage of Co binder phase during cooling.
