Hongyang Li, Cheng Chen, WeiWei Li, Yanjing Zhang, Xiaopeng Liu, Yandong Wang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.2, pp. 47-48, 2011, DOI:10.3970/icces.2011.020.047

Abstract Large numbers of micro lattice plastic deformation of grains set up the macro plastic deformation of polycrystal metallic materials under different macro boundary condition. And the macro homogeneous deformation is in fact the statistical result of micro anisotropic lattice plastic flow. Both of the macro and micro deformation were influenced by intrinsic initial stress, which was intrinsic in the component from micro scale impurity to macro scale non-uniform deformation. In this paper, focused on the engineering application and further damage evaluation, effect of macro initial stress on the macro and micro plasticity deformation of sample More >

Shuguang Li

The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.1, pp. 23-24, 2011, DOI:10.3970/icces.2011.020.023

Abstract Unit cells have been found as an empowering tool for the characterisations of modern composites. The author is honoured to have contributed to the establishment of a systematic methodology for the formulation of unit cells in the past decade through over a dozen of publications on this specific topic.
The formulation of a unit cell could start as if it was a trivial exercise, at least as sometimes perceived by some users, where casual treatments have been found as a result. However, it could soon become overwhelming in order to stand scrutiny and to deal with… More >

Y.S. Chen, Y.H. Huang, B. Yeung, L. Liu, Y.Y. Hung

The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.1, pp. 21-22, 2011, DOI:10.3970/icces.2011.020.021

Abstract Active thermography is an optical-based non-contact inspection method for full-field and quantitative measurement of surface radiation to predict potential faults or inner structure of a test object. The mechanism of the active thermography inspection is to excite the test object using appropriate thermal excitation methods and measure the corresponding thermal response. Active thermography conducts testing in a more controllable way and offer more reliable results compared to passive thermography. This paper reports the development of integrated systems featured some advanced excitation methods and thermal image processing methods. Experiments have been conducted on samples with disbonds, More >

Xide Li

The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.1, pp. 13-14, 2011, DOI:10.3970/icces.2011.020.013

Abstract The quantitatively assessment of defect characteristic parameters (DCP), such as coordinates, size, embedding depth and type of defects in structures or materials, is becoming increasingly important. One reason is for economy and safety, and the other for a defect in structures may lead to failure while it is growing to a critical size. Therefore, it is possible to estimate both remaining life of structures and extent of the degradation by knowing the dimensions of defects presenting in structures. In this paper, several research topics on quantitative detection of the DCP in our group are reviewed… More >

Dongsheng Zhang

The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.1, pp. 5-6, 2011, DOI:10.3970/icces.2011.020.005

Abstract Composites which are considered to be a sort of high-performance materials have been used in the aerospace industry, as well as other industries. Due to the high quality standards and the applicable safety purposes, highly precise and non-destructive test methods are highly demanded for both manufacturing and maintenance. This talk describes the portable shearography device which is developed in Shanghai University. The laser projection and inspection sensor are integrated and mounted on the tripod to meet the requirement of field inspections. Two loading systems including thermal and vibrating are introduced to achieve repeatable test results. More >

Y. H. Huang, S. Y. Hung, Y. S. Liu, Y. Y. Hung

The International Conference on Computational & Experimental Engineering and Sciences, Vol.20, No.1, pp. 1-2, 2011, DOI:10.3970/icces.2011.020.001

Abstract Coherent optical metrology represents a broad scope of techniques using coherent or partial coherent light as a probing matter for various measurements including refractive index, deformation, 3D shape, velocity, temperature, pressure etc. Phase retrieval places a central role in various coherent techniques such as optical nondestructive testing (NDT), surface plasmon resonance (SPR) optical biosensors, laser Doppler vibrometry (LDV), digital holography, optical coherence tomography (OCT) and spectral phase interferometry for direct electric-field reconstruction (SPIDER). Different phase retrieval schemes have been applied in different applications to meet their specific requirements. This article tends to provide a brief More >

Jiahui Pan, Ken Chiavone, Neil Hubble, Ryan Curry

The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.4, pp. 105-106, 2011, DOI:10.3970/icces.2011.019.105

Abstract Recently a number of changes have occurred in electronic packaging, such as increased contact density in both packages and substrates, high reflow temperature due to Pb-free conversion, new materials, new package configurations and new fabrication processes. All these trends demand tighter mechanical tolerances and increase the challenges in modern electronic assembly. Consequently surface flatness plays a more important role in the design and manufacturing process. Warpage introduced by dissimilar CTE (Coefficient of Thermal Expansion) can cause die cracking, solder joint opens, and solder joint cracking. Characterization of the thermally-induced warpage is proving to have significant… More >

R. Muhammad*, A. Maurotto, M. Demiral, A. Roy and V.V. Silberschmidt

The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.3, pp. 95-96, 2011, DOI:10.3970/icces.2011.019.095

Abstract Analysis of the cutting process in machining of modern engineering materials (Ti- and Ni-based alloys), which are hard-to-cut materials, is a challenge that needs to be addressed. Machining of these alloys with conventional techniques is difficult and often results in tool failure due to the high cutting forces imposed on the tool. In a machining operation, cutting forces causes severe deformations in the proximity of the cutting edge, producing high stresses, strain, strain-rates and temperatures in the workpiece.
Ultrasonically assisted turning (UAT) is an advanced machining process, which has shown several advantages especially in the… More >

Qiang Wang, Tie Liu, Yin Liu, Yi Yuan, Jicheng He

The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.3, pp. 89-90, 2011, DOI:10.3970/icces.2011.019.089

Abstract Recently, the application of high magnetic fields to materials processing is considering a promising approach to prepare functional materials with special performances. In the present study, based on the techniques of solidification, quenching, and isothermal annealing in both the semisolid and melting states in high magnetic fields, the solidified structure evolution of the Mn-Sb and Al-Ni alloy systems was systematically studied under different magnetic field conditions. A novel method was proposed to in situ fabricate the graded or aligned materials using gradient or uniform high magnetic fields. The results show that the primary MnSb particles… More >

Li Shan, Ming Cheng, Kaixin Liu

The International Conference on Computational & Experimental Engineering and Sciences, Vol.19, No.3, pp. 87-88, 2011, DOI:10.3970/icces.2011.019.087

Abstract In the present paper, a combined scheme of discrete element method (DEM) and meshless method for numerical simulation of impact problems is proposed. Based on the basic principle of continuum mechanics, an axisymmetric DEM framework is estabilished for modeling the elastoplastic behavior of solid materials. A failure criterion is introduced to model the transformation from a continuum to a discontinuum. The friction force between contact elements is also considered after the failure appears. So our scheme can calculate not only the behavior of continuum and discontinuum, but also the transformation process from continuum to discontinuum. More >