Abstract This study discusses the deformation mechanisms active during high temperature compression tests of the Ni-base superalloy ATI 718Plus®. Deformation twins were observed in deformed grains across a range of temperatures and strain rates by use of transmission electron microscopes (TEM). Even at strain rates as low as 0.01 s − 1 and temperatures up to 1025∘C the microstructure contained of grains which deformed by deformation twinning. It was concluded that the low stacking fault energy of the alloy, which was measured to be 15mJm − 2 caused the formation of the deformation twins. In addition, several examples of the early stages of twin formation were captured. The twinning partials were in most cases emitted from grain boundaries. In a second instance cross-slip events from a Frank-Read source lead to the formation of partials which formed stacking faults.

中文翻译：

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镍基高温合金 ATI 718Plus® 在高温压缩试验中的变形孪晶

摘要 本研究讨论了在镍基高温合金 ATI 718Plus® 的高温压缩试验中活跃的变形机制。使用透射电子显微镜 (TEM) 在一系列温度和应变速率下观察变形晶粒中的变形孪晶。即使在应变速率低至 0.01 s − 1 和温度高达 1025∘C 的情况下，微观结构也包含通过变形孪生变形的晶粒。结论是合金的低堆垛层错能，测量为 15mJm - 2 导致变形孪晶的形成。此外，还捕获了孪生形成早期的几个例子。在大多数情况下，孪晶部分是从晶界发出的。