NiSn4 formation during the solidification of Sn-Ni alloys

► NiSn4 has been found to form during solidification of Sn-rich Sn-Ni alloys. ► No stability range was found for NiSn4 at 220-330 °C. ► Both Ni3Sn4 and NiSn4 crystals grew in hyper-eutectic compositions. ► The Sn-NiSn4 eutectic has a strongly preferred orientation relationship with low lattice disregistry between the phases.