Early Characterization of NdFeB and NdFeB /Co-Al Composites of Sintering Using SPS

Abstract:

The purpose of this study is to obtain a permanent magnet end-product from NdFeB and NdFeB / Co-Al composite material from SPS sintering which has high density with small grain size and strong corrosion resistance. NdFeB powder and NdFeB/Co-Al composites (0.2 and 0.5weight%) of several micron-sized particles resulting from the milling process have been successfully sintered with a temperature parameter of 800°C for 10 minutes and a pressure of 50MPa in dies with a diameter of 20 mm in a vacuum chamber. Optical micrographs show that the grains are uniformly and smoothly distributed throughout the surface. This is showing the types of grain distributions which has good mechanical properties. The X-ray analysis result shows the phase analysis confirms the presence of such main PM phases as Nd, Fe and B. From SEM observation, the particles have irregular shapes and a large particle size distribution. The density value of the sample is in the range of 7.1 - 7.3. From the density measurement it is also known that the sintering sample with SPS has a high-density level which is close to 100%, so it can be said that it has formed fully dense.

• Periodical: Key Engineering Materials (Volume 855)
• Pages: 102-107
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.855.102
• Online since: July 2020
• Authors: Salim Mustofa*, Setyo Purwanto, Sumaryo Sumaryo, Bambang Sugeng, Toto Sudiro, Bambang Hermanto, Nanang Sudrajat
• Keywords: Coercivity, Fully Dense, NdFeB, Permanent Magnet, Sintering, Spark Plasma Sintering

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