Compaction of bulk amorphous Fe40Ni40P14B6 alloys

TL;DR

This study investigates hot pressing consolidation of bulk amorphous Fe40Ni40P14B6 alloys near their supercooled liquid region, highlighting the temperature-dependent fusion process and the balance between amorphous retention and crystallization.

Contribution

It demonstrates the specific temperature conditions for effective bonding of amorphous alloys with minimal crystallization during hot pressing.

Findings

Full fusion occurs near 675 K with ~90% amorphous phase retention.

Lower temperatures prevent bonding due to high viscosity.

Exceeding optimal temperature causes crystallization and embrittlement.

Abstract

The consolidations of two bulk amorphous Fe40Ni40P14B6 alloy discs are performed via hot pressing for a short time in its supercooled liquid region under a pressure of ~1.2 GPa. When the consolidated temperature Ts is lower, the conjunction of two bulk amorphous Fe40Ni40P14B6 alloy discs cannot be achieved. Only when Ts get to the vicinity of 675 K, two amorphous Fe40Ni40P14B6 alloy discs have low viscosity enough to be fully fused together in a short time and the resulting compacts retain ~90% amorphous phase. To further improve the consolidated temperature Ts, a vast amount of crystallization will occur and result in the embrittlement of amorphous alloy.