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Abstract The evolution of metal flow, microstructure and corrosion properties of 5A06 alloy after friction stir welding were studied. Results show that the metal on the advancing side is curled directly into the threads and then is extruded down into the weld nugget zone by complex motions of torsion and swirl. However, the material on the retreating side encounters chaotic flow patterns. The electro backscattering diffraction results indicate that the grains in stir zone are pronouncedly refined by dynamic recrystallization, and the average grain size is about 6 μm. The scanning electron microscope analyses display that β -phase (Al 3 Mg 2) and Al 6 (Mn, Fe) are dispersedly distributed in the stir zone and the Al 6 (Mn, Fe) is smaller than that in base material. The hardness profile is characterized by material softening along the cross-section and the minimum hardness (HV) value of 720 MPa is located in the interface between stirring zone and thermo-mechanically affected zone. It is evident that the stir zone exhibits better corrosion resistance than the base material. The corrosion potential of stir zone is 35 mV larger than that in base material (−0.725 V). [ABSTRACT FROM AUTHOR]

The effects of Cd on the microstructure and the mechanical properties of Mg-Cd magnesium alloy were investigated. The Mg-Cd binary magnesium alloy was analyzed by metallograph, XRD, SEM and EDS examinations. The results show that the microstructure of the Mg-Cd magnesium alloy is refined obviously by adding a little amount of Cd. When Cd addition (wt%) is from 0% to 0.7%, the alloy is composed of α -Mg matrix. Cd dissolves in the matrix to form a solid solution, and there is no new phase formed, which contributes to the increase of the impact toughness, Brinell hardness of the experimental alloy by 52.9%, 11.9%, respectively. With the Cd content increasing, the mechanical properties of Mg-Cd magnesium alloy are improved accordingly. [ABSTRACT FROM AUTHOR]

In this study, on-line NIRs (Near Infrared Spectroscopy) monitoring technology, as a useful tool, has been verified during the extraction process of Flos Lonicera Japonica. To gain representative samples and accurate model result, the detrimental effects from NIR collecting circumstance were significantly reduced with meticulous designs. Based on what, different batches of Flos Lonicera Japonica material were real-time monitored in the extraction process. 10 design schemes were used to verify whether or not different batches could disturb predictive results of the quantitative model. According to a series of chemometric indicators, such as SEC, SECV, SEP, RPD, it is concluded that PLS models established by samples of different batches of raw herbs from the same source could be used to monitor the extraction process with acceptable accuracy. Our research has demonstrated that on-line NIRs monitoring technology as a fast, non-destructive and realtime monitoring tool could be utilized in traditional Chinese medicine preparation [ABSTRACT FROM AUTHOR]