Synthesis of defect-free single-phase bars of high-melting Laves phases through modified cold crucible levitation melting

Laves phases are the most abundant intermetallic phases. However, their mechanical properties are only poorly understood due to difficulties in producing defect-free samples which are large enough for mechanical testing. By using a modified cold crucible levitation melting technique with in situ heat treatment and subsequent defined cooling, massive and large bars of several hundreds of grams of brittle and high-melting Laves phases were produced. Metallographic investigation revealed single- or near single-phase microstructures and a homogeneous chemical composition within the cast ingots with a diameter of 15 mm and of more than 100 mm length. With these high-quality bars it is now possible to prepare large samples that can be used for obtaining mechanical data of these phases.

Research highlights▶ Cold crucible melting with in situ heat treatment applied for brittle intermetallics. ▶ Crack-poor, single-phase Laves phase material for large samples is produced. ▶ Mixing materials with high gradients of melting points are unproblematic. ▶ Temperature dependant Young's modulus measurement is applied for the first time.