Method for producing high stacking fault energy (SFE) metal films, foils, and coatings with high-density nanoscale twin boundaries

    公开(公告)号:US10023977B2

    公开(公告)日:2018-07-17

    申请号:US14428538

    申请日:2013-09-17

    IPC分类号: C30B29/68 C30B29/02

    摘要: Materials, including metals such as bulk metals, specialty alloys, metallic films and coatings, are made up of many tiny single crystals, which may also be referred to as grains. The boundaries between crystals are called grain boundaries and govern properties such as mechanical strength, deformation, and electrical resistivity. These properties are affected by not only the number of grain boundaries formed, but also the density and orientation of those grain boundaries. Twin boundaries are a special type of grain boundary which have symmetrical “mirror image” structures and preserve favorable qualities of grain boundaries while suppressing unfavorable properties such as the initiation of cracks, inclusions, and other unwanted flaws. Some metals and alloys form twins more easily than others during processing. Metals with low stacking fault energy (SFE) such as austenitic stainless steel, copper (Cu), and silver (Ag) form twin boundaries more easily than metals with high SFE such as Magnesium (Mg) and Aluminum (Al).