Diffuse-interface polycrystal plasticity: Expressing grain boundaries as geometrically necessary dislocations

The standard way of modeling plasticity in polycrystals is by using the crystal plasticity model for single crystals in each grain, and imposing suitable traction and slip boundary conditions across grain boundaries. In this fashion, the system is modeled as a collection of boundary-value problems with matching boundary conditions. In this paper, we develop a diffuse-interface crystal plasticity model for polycrystalline materials that results in a single boundary-value problem with a single crystal as the reference configuration. Using a multiplicative decomposition of the deformation gradient into lattice and plastic parts, i.e. F(X,t) = F^L(X,t) F^P(X,t), an initial stress-free polycrystal is constructed by imposing F^L to be a piecewise constant rotation field R^0(X), and F^P = R^0(X)^T, thereby having F(X,0) = I, and zero elastic strain. This model serves as a precursor to higher order crystal plasticity models with grain boundary energy and evolution.Comment: 18 pages, 7 figure

The Green tensor of Mindlin's anisotropic first strain gradient elasticity

We derive the Green tensor of Mindlin's anisotropic first strain gradient elasticity. The Green tensor is valid for arbitrary anisotropic materials, with up to 21 elastic constants and 171 gradient elastic constants in the general case of triclinic media. In contrast to its classical counterpart, the Green tensor is non-singular at the origin, and it converges to the classical tensor a few characteristic lengths away from the origin. Therefore, the Green tensor of Mindlin's first strain gradient elasticity can be regarded as a physical regularization of the classical anisotropic Green tensor. The isotropic Green tensor and other special cases are recovered as particular instances of the general anisotropic result. The Green tensor is implemented numerically and applied to the Kelvin problem with elastic constants determined from interatomic potentials. Results are compared to molecular statics calculations carried out with the same potentials

Strengthening SMEs to make export competitive

The importance of SMEs in any economy cannot be overlooked as they form a major chunk in the economic activity of nations. India has nearly three million SMEs, which account for almost 50 per cent of industrial output. However, SMEs which form the backbone of industrial development in India are not export competitive and contribute only about 34 percent of exports. It is this feature of the SMEs that make it an ideal target to realize its potential export competitive. Drawing from the experiences of countries that have successfully promoted the export competitiveness of SMEs, this paper has identified ways in which SMEs in India can have an access to external markets through exports, which include simplification of procedures, incentives for higher production, preferential treatments to SMEs in the market development fund, linking up SMEs with Transnational Companies or large domestic exporting firms; and formation of clusters and networks in order to reinforce their external competitiveness.Small and Medium Enterprises (SMEs), SWOT Analysis, Export, India

Statistics of grain microstructure evolution under anisotropic grain boundary energies and mobilities using threshold-dynamics

This paper investigates the statistical behavior of two-dimensional grain microstructures during grain growth under anisotropic grain boundary characters. We employ the threshold-dynamics method, which allows for unparalleled computational speed, to simulate the full-field curvature motion of grain boundaries in a large polycrystal ensemble. Two sets of numerical experiments are performed to explore the effect of grain boundary anisotropy on the evolution of microstructure features. In the first experiment, we focus on abnormal grain growth and find that grain boundary anisotropy introduces a statistical preference for certain grain orientations. This leads to changes in the overall grain size distribution from the isotropic case. In the second experiment, we examine the texture development and growth of twin grain boundaries at different initial microstructures. We find that both phenomena are more pronounced when the initial microstructure has a dominant fraction of high-angle grain boundaries. Our results suggest effective grain boundary engineering strategies for improving material properties.Comment: 25pages, Figure

Private Sector Management Tools In The Public Sector: Illustrative Evidence Of Literature From Australian Public Sector

Public sector reform processes have brought a wide range of improvements in many areas of public service delivery. This study explores the reforms activities initiated by Australian public sector organizations in the context of new public management ideals. New public management ideals believe that management in the public sector is not different from management in the private sector. Since 1980s the Australian public sector has been dominated by the new public management principles as a response to reform initiatives and eventually different private sector management practices have been introduced in public sector. Literature supports that the Australian public sector organizations have changed their structure and operation in line with the private sector to achieve cost-efficiency, budget accountability and an improved customer focus in service delivery. However, this study doesn’t intent to generalize any findings rather highlights a summary based on available literature. Though the context of the present research is Australia, it may be equally useful to every policy maker who are engaged in formulating new policies for respective public sector. Moreover, the findings reported in this study would be useful to the public sector managers in their day to day decision-making

Conceptualising management control systems. Illustrative evidence from literature on the Australian business sector

This study is an attempt to conceptualise management control systems. Management control systems can be viewed as a broader concept which includes different components and used for varying purposes. In an organisation, control is applied at different levels and is directly related with employees of the organisation concerned. To comprehend the basics of management control systems the present study will explore the typography of the control mechanisms. Management control systems can be viewed as technical activity which is implemented in different ways in different countries. In the Australian business sector these control tools have been widely used. This study will review the experiences of implementing management control systems in the Australian business sector. Though the present study is based on Australian business sector it has policy implications to other countries and is expected to indicate potential usefulness to management control practices

Life cycle costing: an alternative selection tool

In today’s complex business environment, both raising and application of fund becomes so costly. Thus, business needs to take a wise decision of investing funds in fixed facilities, which at one side consumes a lot of costly fund and on the other, set the value of the business. Net present value (NPV), pay back period (PBP), internal rate of return (IRR) are some widely used and customary tools in such situation most of which are based on projected revenues. In this paper, we have tried to use life cycle costing as a strong alternative, which considers every cost category throughout the life of the assets, from cradle to grave, to represent the effective use of funds in its totality. The theoretical foundation of LCC as a tool comes from literature review but the application of LCC in alternative choosing areas are the development of the authors. The use of mathematical tools and equations is an exemplary one that may be changed or modified to fit it with the typical context, if necessary. The paper can be a guideline which finally concludes that the use of life cycle costing as an alternative selection tool results a better cost structure analysis than others.Cost Breakdown Structure (CBS), Invisible Costs, Iceberg Effect, Affinity Diagram