The superplastic properties of Avesta 2304, an#alpha#/#gamma# microduplex stainless steel, have beenexamined over the temperature range 880 to 1000 deg C and anaverage strain rate sensitivity of 0.8 recorded for the superplasticrange of strain rates encompassing 10~ (-4) to 10~ (-3)/s. Theflow behaviour of Avesta 2304 can be described by: #epsilon#=(3.3×10~6 #epsilon#~ (1.2)+2×10~3 #epsilon#~ (3.2)) exp (~(-210000)/RT)/T where ## is expressed in MPa and the strain rate ins(-1). Diffusion bonding studies were also carried out at 940 degC and sound bonds could be developed within 30 minutes for anapplied pressure of 3MPa. Indicating the DB/SPF of Avesta 2304should be feasible using existing equipment and process cyclesdeveloped for Ti-6Al-4V. The kinetics of interfacila void removalwere also measured and showed good agreement with theory.
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