Hafnium - Tantalum - Tungsten

Ekaterina V. Belova, Ilya B. Kutzenok

Introduction

Extremely high melting points and important mechanic properties make us expect that hafnium, tantalum and tungsten and their alloys can be good materials for power, cosmic and nuclear industry, e.g. space fission reactors [2007Bus]. Some of tantalum alloys with hafnium and tungsten offer excellent formability and ductility at low temperatures while showing good high temperature strength and alkali metal compatibility. Investigations of the Hf-Ta-W phase relations, structures, and thermodynamics are presented in Table 1. First studies on alloys were reported by [1961Fei, 1965Klo]. [2007Leo] mentioned that experimental studies of these alloys which had been conducted in NASA, stopped due to lack of funding in 70s. Phase equilibria were reported only in the Ta-rich region [1965Klo]. [2007Leo] studied aging of Hf_{2Cited references - 10, figures - 1, tables - 3, chapters - 7}