Phase structures and electrochemical properties of the laser sintered LaNi5–x wt.% Mg2Ni composites

The LaNi5–x wt.% Mg2Ni (x = 10, 20 and 30) composites were fabricated by a new sintering method. The phase structures and electrochemical properties of the laser sintered LaNi5–Mg2Ni composites were studied. It was found that LaNi5–10 wt.% Mg2Ni consists of a major phase (PuNi3-type) and a secondary phase (LaNi5). The LaNi5 bars distribute along the laser scan direction. Besides a small amount of LaNi5 and MgNi2, there are LaNi4Mg and LaMg2Ni9 phases in the samples with x = 20 and 30. These samples with x = 20 and 30 showed that the LaNi5 cores are surrounded by the shells of LaNi4Mg, LaMg2Ni9 and MgNi2. These ternary La–Mg–Ni phases and microstructures influence the electrochemical properties of the LaNi5–Mg2Ni composites.