Ahmad Wasim

Modeling of cutting speed (CS) for HSLA steel in wire electrical discharge machining (WEDM) using moly wire

Abstract The high capital costs of wire electrical discharge machining (WEDM) equipment necessitate optimal utilization of the WEDM process and equipment. Cutting speed (CS) is a key performance measure to achieve this objective. However, process parameters of WEDM greatly hamper CS and hence productivity and machining efficiency. It is therefore essential to pick the right combination of parameters to attain better CSs. In this paper, five process parameters which include pulse on-time, pulse off-time, pulse frequency, power, and wire speed were used to develop an empirical relationship between process parameters and CS. A regression model based on experimental data was developed and validated through confirmation tests. Experiments have been conducted on high-strength low-alloy steel using molybdenum wire. Analysis of variance was applied to segregate significant process parameters and it was revealed that pulse off-time, power, and pulse frequency were the major parameters affecting CS. Contour plots have been established to select the best process parameters in addition to the developed model. Stability of moly wire was also explored using scanning electron microscope and energy dispersive spectroscopy analysis. Results showed that moly wire retains its original surface quality and dimensions which contributes to dimensional accuracy of parts.

Manufacturing Cost Modelling for Aerospace Composite Applications

The application of composites has been increasing dramatically in aerospace structures recently, for example, composites have contributed over 50 % of the structure mass of large transport airplanes. However, the further usage has been restricted because of the high material and manufacturing costs. Hence, it is essential to utilise cost estimation tools for accurate cost estimation in the early design stages, and then efficient decisions and design optimisations could be made to reduce the cost of composite products. A cost modelling system has been developed for aerospace CFRP composites, which can help designers and cost engineers to estimate the manufacturing cost in early development stages. The system consists of several modules: material selection, process planning, cost estimation, cost reporting and a user friendly interface. Moreover, the selection and planning modules are combined with databases, including material and process.

Continuous Quality Improvement (CQI) framework: A case of industrial engineering department

This paper aims to present an educational framework for outcomes based continuous quality improvement. Well defined program outcomes, program educational objectives and assessment process have been developed to ensure graduates’ outcomes achievement. Direct and indirect tools have been used for assessment process. Course evaluation surveys, alumni surveys, and employer surveys have been deployed for indirect outcome assessment. Exams, quizzes, assignments and projects, on the other hand, have been used for direct outcome assessment. In developed framework, the educational processes committees and facilities committees have been integrated to continuously evaluate and monitor the educational processes. Furthermore, program outcomes and course learning outcomes are proposed to be evaluated and continuously monitored by programs goals committee and continuous course improvement committee respectively. Forms and procedures have been developed to assess student outcomes.

Finite Element Analysis Process in Design Engineering: Best Practice

The fear of knowledge loss by experts retiring or leaving the company forces the company to capture the experts’ knowledge and manage it appropriately for future use. This paper aims to capture the best practice for the Finite Element Analysis process in design engineering environment. There are three initial phases in developing FEA models which are classification of the problem, discretization and Modelling. The modelling stage has further classified to three steps, namely: pre-processing, analysis and post-processing. The best practice was captured through different mechanisms including interviews, observation, literature studies and practically using the finite element tools. The captured knowledge will be helpful to improve the current FEA techniques and to accelerate the learning curve for new employee joining the company.