At the eastern Qilian Shan mountain front in the NE Tibetan Plateau, the Minle‐Damaying Fault (MDF), the southernmost fault of the North Frontal Thrust (NFT) system, has previously been proposed as an inactive structure during the Holocene. Here we present a detailed record of six strath terraces of the Xie River that document the history of active deformation of the MDF. One optically stimulated luminescence dating sample constrains abandonment of the highest terrace T6 at 12.7 ± 1.4 ka. The formation ages of the lower terraces (T4–T1) are dated by AMS 14C dating. The cumulative vertical offsets of the MDF recorded by these terraces are determined as 12.2 ± 0.4 m (T6), 8.0 ± 0.4 m (T5), 6.4 ± 0.4 m (T4), 4.6 ± 0.1 m (T3), and 3.2 ± 0.2 m (T1c) by an unmanned aerial vehicle system, respectively. A long‐term vertical slip rate of the MDF of 0.9 ± 0.2 mm/yr is then estimated from the above data of terrace age and vertical offset by a linear regression. Assuming that the fault dip of 35 ± 5° measured at the surface is representative for the depth‐averaged fault dip, horizontal shortening rates of 0.83–1.91 mm/yr are inferred for the MDF. Our new data show that the proximal fault (the MDF) of the NFT system at the eastern Qilian Shan mountain front has remained active when the deformation propagated basinward, a different scenario from that observed at both the western and central Qilian Shan mountain front.

The effects of solution treatment time and Si content and morphology on microstructures and mechanical properties of heat-treated Al-Si-Mg cast alloys were investigated systematically. Five alloys, with Si levels ranging from 1 to 13 pct, were tested in as-cast, T4, and T61 conditions. The eutectic Si was both unmodified and Sr-modified. Results show that the microstructures are affected significantly by alloy composition, eutectic Si morphology, and solution treatment time. Si content has significant effects on ultimate tensile strength (UTS), yield strength (YS), and elongation as well as a strong influence on solution treatment response. In T61 treatment with different solutionizing times, UTS and YS reach their maximum values iñ 1 hour of solutionizing followed by a decrease, then a slight increase, and finally, a plateau close to the maximum level. Elongation of alloys with a high Si content, 7 pct and 13 pct, increases rapidly at solutionizing times of 1 to 2 hours then varies in a wide range, showing improvements in the 4 to 10 hours range. The data indicate that a solution treatment time of 1 hour is sufficient to achieve maximum strength. The changes in mechanical properties were correlated to changes in microstructure evolution-Mg-Si precipitation, Si particle fragmentation, and microstructure homogenization. Empirical models uniquely relating Si content to UTS and YS are given for T61 heat-treated alloys.

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Induction heating is one of the most popular metal heating technologies due to its high heating rate and high energy efficiency. This method is suitable for heating workpieces/blanks in different shapes, sizes and materials. Although induction heating of metal sheets has already been investigated by various research organizations and industrial companies, information concerning the induction heating of aluminium blanks is limited. Considering that hot stamping of aluminium sheets for automotive and aerospace applications is currently attracting a lot of attentions, it is timely important to gain more understanding on this technology by conducting in-depth investigations. Especially, investigations are required to address issues relating to the uneven temperature distributions developed in the metal sheets when they are heated, so that optimum designs could be obtained to improve the technology and its applications. This paper presents an in-depth analysis conducted recently for the investigation into heating schemes and process parameters in induction heating of aluminium sheets, mainly using 3D FE simulations, based on a general experimental validation. Different material, coil geometric and power-setting factors were considered during the modelling and analysis to examine their effects on the heating efficiency and developed temperature profiles. It was revealed from the simulations that design features of the induction coils affect the uniformity of the developed temperatures in the metal sheets. It is shown that an optimised combination of the coil design and the power setting could help to achieve higher heating rates, at the same time, also to achieve higher temperature-distribution uniformity. At the end of this paper, a discussion of practical factors that affect applications of induction heating of aluminium sheets for hot stamping applications is presented.