Papers by Author: Jian Wu

Abstract: Use the standard 750ml bottle of red wine packaging design to explore the honeycomb core module of digital design and green manufacturing approach to virtual design and virtual manufacturing of new structural approach to packaging product development, through the final product form of reverse thrust reversers honeycomb core module data and processing forms, and finally the use of CNC machining centers cellular module manufacture.

Abstract: Based on the actual process for smelting cold heading steel, this article adopts the single-slag process to smelt the low-carbon, low-silicon and high-alumina cold heading steel SWRCH6A, so as to study the effect of technological factors of the smelting process on the change of molten steel component in various working procedures and steel properties. The results show that, the smelting process control level for smelting high-Al cold heading steel using single-slag process is improved, the content change for main elements in the steel, w[Al]t and calcium treatment effect are stable, w[C] and w[Si] have a close relationship with w[P] and w[S]. The calcium yield after calcium treatment by single-slag process has a linear relation with w[Ca], and η_Ca=2323.4*w[Ca] -1.040. The maximum calcium yield may reach 21%. All the mechanical properties of cold heading steel exceed the ML08Al standard. The smelting cold heading steel using single-slag process can fully reach the property requirements for cold heading steel grade.

Abstract: This paper reports recent progress in the development of high power 4H-SiC BJTs based on an improved device design and fabrication scheme. Near theoretical limit high blocking voltage of VCEO=1,836 V has been achieved for 4H-SiC BJTs based on a drift layer of only 12 μm, doped to 6.7x1015 cm-3. The collector current measured for a single cell BJT with an active area of 0.61 mm2 is up to IC=9.87 A (JC=1618 A/cm2). The collector current is 7.64 A (JC=1252 A/cm2) at VCE=5.9 V in the saturation region, corresponding to an absolute specific on-resistance (RSP_ON) of 4.7 m9·cm2. From VCE=2.4 V to VCE= 5.8 V, the BJT has a differential RSP_ON of only 3.9 m9·cm2. The current gain is about 8.8 at Ic=5.3 A (869 A/cm2). This 4H-SiC BJT shows a V2/RSP_ON of 717 MW/cm2, which is the highest value reported to date for high-voltage and high-current 4H-SiC BJTs. A verylarge area 4H-SiC BJT with an active area of 11.3 mm2 is also demonstrated.