The Role of Nano-sized Fraction on Spark Plasma Sintering the Pre-Alloyed Spark-Erosion Powders

Abstract

Ti-Ni-Hf, Ni-Al and Cu-Al-Ni shape memory materials were produced by spark plasma sintering method from the micron and nano-sized particles prepared by spark-erosion method in cryogenic liquid from preliminary melted master alloys. The effects of spark plasma sintering processing parameters on the martensitic transformation and microstructure of the sintered compacts were investigated using XRD and SEM methods. Although precipitating processes were usually not completely depressed, the intensive grain growth was also not found in most cases. Most of the microstructure peculiarities of as processed powder were inherited by the sintered material. The contradictory role of the nano-sized fraction of powders is discussed: in most case this fraction promotes the rapid sintering but also the oxidation proceses in sintered compacts. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/24890