Effect of Temperature Cycling Pretreatment on the Thermal Stability of Sm(Co, Fe, Zr, Cu) Magnets in the Mild Temperature Range.

The irredeemable magnetic losses of Sm(Co, Fe, Zr, Cu) permanent magnets caused by oxidation are very important for their practical application. In this work, the simulated results with ≥ 98% based on the data of the temperature cycling test and the long-term isothermal test for the original samples confirmed that the magnetic flux losses reached 9.38% after the 5000th cycle in range R.

Mirror-like Bright Al-Mn Coatings Electrodeposition from 1-Ethyl-3 Methylimidazolium Chloride-AlCl-MnCl Ionic Liquids with Pyridine Derivatives.

The effects of three pyridine derivative additives, 4-hydroxypyridine, 4-picolinic acid, and 4-cyanopyridine, on Al-Mn coatings were investigated in 1-ethyl-3-methylimidazolium chloride-AlCl-MnCl (EMIC-AlCl-MnCl) ionic liquids. The smooth mirror-like bright Al-Mn coatings were obtained only in the EMIC-AlCl-MnCl ionic liquids containing 4-cyanopyridine, while the matte Al-Mn coatings were electrodeposited from EMIC-AlCl-MnCl without additives or containing either 4-hydroxypyridine or 4-picolinic acid. The scanning electron microscope and X-ray diffraction showed that the bright Al-Mn coatings consisted of nanocrystals and had a strong (200) preferential orientation, while the particle size of matte Al-Mn coatings were within the micron range.