Spark plasma sintering and hydrogen pre-annealing of copper nanopowder

作者：Monnier Judith^*; Champion Yannick; Perriere Loic; Villeroy Benjamin; Godart Claude

来源：Materials Science and Engineering A-Structural Materials Properties Microstructure and Processing, 2015, 621: 61-67.

DOI：10.1016/j.msea.2014.10.040

• Microstructures
• Nanostructured copper
• Spark Plasma Sintering
• Surface oxidation

Copper nanopowders were sintered using Spark Plasma Sintering (SPS). Special attention was paid to the presence of natural surface oxide and reductive thermal treatments under H-2 atmosphere were carried out to remove it. The sintering mechanisms were investigated by the means of disrupted experiments at various temperatures to reach different shrinkage rates. Optimized experiments were also carried out to reach a maximum densification. The samples were characterized and compared using density measurement, X-ray diffraction, mechanical tests (tension and compression) and analysis of the fracture surfaces with scanning electron microscope. On the one hand, it results that during the SPS treatment, the raw powder undergoes a series of oxide transformations from CuO to Cu2O. On the other hand, reductive treatment drastically decreases the sintering temperature, from 650 degrees C to 260 degrees C, to reach 90% density without grain growth. Higher mechanical strength, up to 750 MPa, also shows better consolidation.

• 出版日期2015-1-5