The research works of graphene-reinforced metal matrix composites will be summarised in this paper. Comparatively, much less research works have been undertaken in this field. Graphene has been thought to be an ideal reinforcement material for composites due to its unique two-dimensional structure and outstanding physical and mechanical properties. It is expected to yield structural materials with high specific strength or functional materials with exciting thermal and electrical characteristics. This paper will introduce all kinds of graphene-reinforced metal matrix composites that have been studied. The microstructure and mechanical properties, processing techniques, graphene dispersion, strengthening mechanisms, interfacial reactions between graphene and the metal matrix and future research works in this field will be discussed.

This article studies the transient weld pool dynamics under the periodical impingement of filler droplets that carry mass, momentum, thermal energy, and species in a moving 3D gas metal arc welding.The complicated transport phenomena in the weld pool are caused by the combined effect of droplet impingement, gravity, electromagnetic force, plasma arc force, and surface tension force (Marangoni effect). The weld pool shape and the distributions of temperature, velocity, and species in the weld pool

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Facility location, inventory control, and vehicle routes scheduling are critical and highly related problems in the design of logistics system for e-business. Meanwhile, the return ratio in Internet sales was significantly higher than in the traditional business. Many of returned merchandise have no quality defects, which can reenter sales channels just after a simple repackaging process. Focusing on the existing problem in e-commerce logistics system, we formulate a location-inventory-routing problem model with no quality defects returns. To solve this NP-hard problem, an effective hybrid genetic simulated annealing algorithm (HGSAA) is proposed. Results of numerical examples show that HGSAA outperforms GA on computing time, optimal solution, and computing stability. The proposed model is very useful to help managers make the right decisions under e-supply chain environment.

A self-aligned Ni-InGaAs metallic source and drain ͑S/D͒ technology for In 0.7 Ga 0.3 As channel n-MOSFETs ͑metal-oxidesemiconductor field-effect transistors͒ is reported. A process was developed for selective contact metallization on InGaAs, comprising a reaction of Ni with In x Ga 1−x As to form a metallic Ni-InGaAs material, and a selective removal of excess Ni using a wet etch. Ni-InGaAs has low sheet resistance, is ohmic on n-In x Ga 1−x As, and forms a Schottky contact on p-In x Ga 1−x As. A selfaligned salicidelike integration scheme was used to realize In 0.7 Ga 0.3 As n-MOSFETs with self-aligned Ni-InGaAs metal S/D. n-MOSFETs with a gate length of 1 m shows good transfer characteristics with an on-state/off-state drain current ratio of ϳ10 3 and peak transconductance G m of 74 S/m. III-V materials such as indium gallium arsenide ͑InGaAs͒ have significantly higher electron mobility than silicon ͑Si͒ and have been explored as alternative channel materials in field effect transistors ͑FETs͒ for logic applications. 1-11 One of the challenges for achieving high drain current I DS performance is the realization of low source and drain ͑S/D͒ series resistance R S/D , which includes metalsemiconductor contact resistance. 12-16 Achieving high S/D doping concentration by ion implantation and annealing is difficult for some III-V materials. To realize low R S/D in III-V FETs, selective growth of in situ doped S/D materials 17-19 and self-aligned contacts are needed. 15,16,19,20 Forming metallic S/D is another attractive option. 21,22 The metallic S/D should preferably be self-aligned. However, a nickel-salicidelike process involving direct reaction of a nongold metal with III-V material for the formation of self-aligned metal S/D has not been demonstrated.In this work, we report a new salicidelike self-aligned NiInGaAs metallization technology and its integration in In 0.7 Ga 0.3 As channel n-MOSFETs ͑metal-oxide-semiconductor field effect transistors͒ to form metal source/drain.

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