The Pressure Compaction of Zr-Nb Powder Mixtures and Selected Properties of Sintered and KOBO-Extruded Zr-xNb Materials

Abstract

Materials were obtained from commercial zirconium powders. 1 mass%, 2.5 mass% and 16 mass% of niobium powders were used as the reinforcing phase. The SPS method and the extrusion method classified as the SPD method were used. Relative density materials of up to 98% were obtained. The microstructure of the sintered Zr-xNb materials differs from that of the extruded materials. Due to the flammability of zirconium powders, no mechanical alloying was used; only mixing of zirconium and niobium powders in water and isopropyl alcohol. Niobium was grouped in clusters with an average niobium particle size of about 10 μm up to 20 μm. According to the Zr-Nb phase equilibrium system, the stable phase at RT was the hexagonal α-phase. The tests were carried out for materials without the additional annealing process. The effect of niobium as a β-Zr phase stabilizer is confirmed by XRD. Materials differed in their phase composition, and for both methods the β-Zr phase was present in obtained materials. A very favorable effect of niobium on the increase in corrosion resistance was observed, compared to the material obtained from the powder without the addition of niobium.

Development of Alternative Method for Manufacturing Structural Zirconium Elements for Nuclear Engineering

“…The microhardness after vacuum heat treatment at the temperature of 580 °C is 150 ± 10 HV 0.05 , and at the temperature of 750 °C, it is 160 ± 10 HV 0.05 and corresponds to the microhardness values of the finished material from the Zr-1Nb alloy obtained by traditional technology [ 4 , 10 ]. What is worth noting is the significantly higher hardness reported by Jaworska et al [ 23 ], where the Zr-1Nb alloy was manufactured by spark plasma sintering. The hardness is >339 HV 2 after spark plasma sintering at 1200 °C and 1 min holding time and depends on the used niobium powder.…”

Recycling of Hard Disk Drive Platters via Plastic Consolidation

“…This method is most commonly used in powder metallurgy to densify the powdered material during the compaction process. The PC process can be carried out not only via traditional extrusion, but also via other deformation methods, such as rolling, forging, hydro-extrusion, and special methods of plastic working [30][31][32][33][34].…”

Microstructure and Mechanical Properties of Al-Si Alloys Produced by Rapid Solidification and Hot Extrusion

“…These methods consist of introducing a large number of defects into the material as a result of plastic deformation, which, after spatial reorganization and mutual reaction, are able to create a large number of grain boundaries and, thus, grain refining. SPD methods are based on plastic deformation with a very high proportion of the compressive hydrostatic stress state, which aims to prevent loss of material cohesion [12][13][14][15].…”