论文标题
基础位错之间的相互作用与$β_1'$沉淀在mg-4zn合金中：机制和增强
Interactions between basal dislocations and $β_1'$ precipitates in Mg-4Zn alloy: mechanisms and strengthening
论文作者
论文摘要
位错/沉淀相互作用以及临界分辨剪切应力的机制是在MG-4 WT中的温度的函数。 ％Zn合金通过Micropillar压缩测试。发现当横截面为$> $ 3 x 3 $μ$ m $^2 $时，机械性能独立于微柱尺寸。透射电子显微镜表明，变形涉及在沉淀物周围弯曲并进行剪切的混合物。初始屈服强度与Orowan模型的预测兼容，该模型的脱位围绕沉淀物弯曲。然而，随后降水剪切占主导地位，导致滑动带的形成，其中杆沉淀物转化为球形颗粒，从而限制了应变硬化。沉淀物剪切的重要性随温度增加，并导致合金的机械性能从23℃降低到100c。
The mechanisms of dislocation/precipitate interaction as well as the critical resolved shear stress were determined as a function of temperature in a Mg-4 wt. % Zn alloy by means of micropillar compression tests. It was found that the mechanical properties were independent of the micropillar size when the cross-section was $>$ 3 x 3 $μ$m$^2$. Transmission electron microscopy showed that deformation involved a mixture of dislocation bowing around the precipitates and precipitate shearing. The initial yield strength was compatible with the predictions of the Orowan model for dislocation bowing around the precipitates. Nevertheless, precipitate shearing was dominant afterwards, leading to the formation of slip bands in which the rod precipitates were transformed into globular particles, limiting the strain hardening. The importance of precipitate shearing increased with temperature and was responsible for the reduction in the mechanical properties of the alloy from 23C to 100C.
