Research Trends and Development Patterns in Language Testing Over the Past Three Decades: A Bibliometric Study.

This study used bibliometric data from Language Testing, a prestigious international peer-reviewed journal in the language testing field, to investigate research trends and development patterns in language testing. The bibliometric information included the number of publications, the most frequently researched test types and topics, the most cited publications and authors (as measured by references), the most prolific countries/regions and institutions and the most frequently collaborating countries/regions. The results showed that interest in language testing has increased over time and that regional tests and international tests have been major concerns, while classroom tests/assessments have received less attention. Research topics were wide-ranging and addressed almost all language testing related issues, among which validity/validation received the highest interest across periods. Moreover, the publications were produced by a wide range of countries/regions and institutions and included collaborative research spanning various institutions and regions, although collaborative publications across countries were relatively scarce. Based on the findings of this study, implications and suggestions have been highlighted for future research, academic agencies and this journal.

Microstructure and Mechanical Properties of High Vacuum Die-Cast AlSiMgMn Alloys at as-Cast and T6-Treated Conditions.

Al-Si-Mg based alloys can provide high strength and ductility to satisfy the increasing demands of thin wall castings for automotive applications. This study has investigated the effects of T6 heat-treatment on the microstructures, the local mechanical properties of alloy phases and the fracture behavior of high vacuum die-cast AlSiMgMn alloys using in-situ scanning electron microscopy (SEM) in combination with nano-indentation testing. The microstructures of the alloys at as-cast and T6 treated conditions were compared and analyzed. It is found that the T6 heat treatment plays different roles in affecting the hardness and the Young's modulus of alloy phases. This study also found that the T6 heat treatment would influence the failure modes of the alloys. The mechanisms of crack propagation in the as-cast and T6 treated alloys were also analyzed and discussed.