Extrusion Study on a Novel Nickel-Based Powder Metallurgy Superalloy WZ-A3

A series of hot extrusion tests were carried out for a novel powder metallurgy superalloy WZ-A3. The effects of extrusion temperature, extrusion speed, and extrusion ratio on the microstructure and the microstructure uniformity of the extruded bar were investigated. The results show that under the conditions of a constant extrusion speed of 35 mm/s, an extrusion ratio of 4.7:1, and an extrusion temperature of 1110 degrees C, completely dynamic recrystallization of the extruded bar occurs. With the increase of the extrusion temperature, the grain coarsens. Under the conditions of a constant extrusion temperature of 1110 degrees C, an extrusion speed of 35 mm/s, and an extrusion ratio of 2.1:1, the recrystallization is incomplete and there are more PPB left. When the extrusion ratio increases to 4:1 similar to 4.7:1, complete recrystallization is achieved, PPB can also be completely eliminated. At an extrusion temperature of 1130. and an extrusion ratio of 4.7: 1, in the extrusion speed range of 20 similar to 50 mm/s, the grains tend to grow much larger. At an extrusion temperature of 1110 degrees C, an extrusion speed of 35 mm/ s, and an extrusion ratio of 4.7:1, the microstructure of the entire extruded bar is rather uniform. From the head of the bar to the tail, the grains are slightly refined. The grains at the edge of the extruded bar are smaller than those of the core and 1/2R.

Automated summary

This study conducted a series of hot extrusion tests on a novel powder metallurgy superalloy WZ-A3 to investigate the effects of extrusion temperature, speed, and ratio on the microstructure and uniformity of the extruded bar. The results revealed that under certain conditions, dynamic recrystallization occurred with grain coarsening. Moreover, the study found significant influences of extrusion temperature, speed, and ratio on the grain size and uniformity of the bar.