Roy McGrann

The effect of coating residual stress on the fatigue life of thermal spray-coated steel and aluminum

Abstract The acceptance of thermal spray coatings in many applications depends on the effect of the coating on the fatigue performance of the coated part. One of the factors that influences the fatigue life of thermal spray-coated components is the residual stress in the coating. This study investigates the fatigue performance of tungsten carbide–cobalt (WC–Co) thermal spray coating systems. Bending fatigue tests of specimens with WC–Co coatings on both 4130 steel substrates and 6061 aluminum substrates were conducted. The through-thickness residual stress level in the thermal spray coatings was determined using the modified layer removal method. The effect of the residual stresses on the fatigue life of the coated specimens was analyzed. It was found that there is a direct relation between the residual stress in the coating and the fatigue life of the coated part. Fatigue life can be changed by a factor of ten due to the level of compressive residual stress in the coating.

The effect of residual stress in HVOF tungsten carbide coatings on the fatigue life in bending of thermal spray coated aluminum

One factor that affects the suitability of tungsten carbide (WC) coatings for wear and corrosion control applications is the fatigue life of the coated part. Coatings, whether anodized or thermal spray coated, can reduce the fatigue life of a part compared to an uncoated part. This study compares the fatigue life of uncoated and thermal spray coated 6061 Al specimens. The relation between the residual stress level in the coating and the fatigue life of the specimen is investigated.Cyclic bending tests were performed on flat, cantilever beam specimens. Applied loads placed the coating in tension. Residual stress levels for each of the coating types were determined experimentally using the modified layer removal method.Test results show that the fatigue life of WC coated specimens is directly related to the level of compressive residual stress in the coating. In some cases, the fatigue life can be increased by a factor of 35 by increasing the compressive residual stress in the coating.

Enhancing Engineering Computer-Aided Design Education Using Lectures Recorded on the PC

Computer-Aided Engineering (CAE) is a course that is required during the third year in the mechanical engineering curriculum at Binghamton University. The primary objective of the course is to educate students in the procedures of computer-aided engineering design. The solid modeling and analysis program Pro/Engineer™ (PTC®) is used as the basis of this course. As a means to this objective, students must be trained to use the Pro/Engineer™ software. We created a series of video lectures using Camtasia Studio (TechSmith®) to accomplish the Pro/Engineer™ training. As the literature for the software says: “Camtasia Studio is a complete solution for quickly creating professional-looking videos of your PC desktop activity.” Thirteen videos were created for this course, which incorporated audio combined with PowerPoint™ slides. The video files (avis) are distributed to students on five CDs. This article describes the structure of the course and how the videos are integrated into it. Also included is a brief overview of the creation of the videos. Results of a survey of student satisfaction with the video format that was used in the course are presented.

Philosophy of technology in engineering education

In reflecting on the philosophy of engineering education as a distinct field, questions from other fields of philosophy are encountered. Among these, in addition to philosophy of education, are: ethics, epistemology, ontology, philosophy of science, and philosophy of technology. Within the philosophy of technology, a discussion of ldquophilosophy of engineeringrdquo has been pursued in recent years. In this paper, the areas described and questions raised by philosophy of technology, specifically philosophy of engineering will be briefly presented. The importance of philosophy of technology for the philosophy of engineering education will be developed. In Teaching About Technology (2005), Marc J. de Vries identified four reasons for engineering educators to become acquainted with philosophy of technology. The reasons are: (1) philosophy of technology can yield insights into curriculum development, (2) it can provide a conceptual basis for understanding technology, (3) it helps position the teaching of engineering among other subjects, and (4) it is helpful in identifying the research agenda in engineering education. Included in this paper will be a discussion of the literature in the discipline of philosophy of technology.

Special session - continuing the FIE 2007 conversation on: Can philosophy of engineering education improve the practice of engineering education?

The purpose of this special session is to continue the conversation began at FIE 2007 that asked the question “Can philosophy of engineering education improve the practice of engineering education? The session is summarised on http://www.ws. binghamton. edu/PhilEngEd/ It has become clear that this debate fits in with a broader and international debate on philosophy of engineering that although not directed at the philosophy of education has outcomes that bear on the curriculum and instruction. Some one hundred papers on engineering philosophy have been published in the last three years. A paper summarizing some of the features of these studies accompanies this discussion in the Proceedings. During the year Smith has revisited his suggested reading on the philosophy of education and that is also in the Proceedings. Together this work has enabled us to refocus the issues in order that as a group we can develop our thinking.

Autonomous Robots as a Generic Teaching Tool

An undergraduate bioengineering laboratory course using small autonomous robots has been developed to demonstrate control theory, learning, and behavior. The lab consists of several modules that demonstrate concepts in classical control theory, fuzzy logic, neural network control, and genetic algorithms. The autonomous agents are easy-to-build, inexpensive kit robots. Each robot functions independently in a real-world environment. Students program and retrieve data wirelessly using handheld computers. The hands-on nature of the lab modules engages students in ways that lectures, readings and software simulations cannot. By interacting with these robots, students directly experience the effects of unexpected environmental factors on designs and deviations from software simulations. The robots are easily adapted for use in many different aspects of two-year college and K-12 STEM education. Students are motivated to understand engineering, math and science principles in order to control the robots. Examples of use of the robots and modules by a local community college are presented

Increasing student-centered learning in a first-year engineering program

This paper analyzes the implementation of a restructured model for activity sections in a first-year engineering program led by graduate teaching assistants. The aim of the new model is to increase student-centered learning and to provide for more uniformity amongst sections led by different graduate teaching assistants. In this program, all freshmen engineering students share a common year during which they are required to take linked Introduction to Engineering and Technical Communications courses. This paper focuses on the Introduction to Engineering course. Following many discussions on possible improvements, along with the results of both student and peer evaluations, a new teaching model was designed and has been implemented. In this paper, both the old and the new model, assessment tools, and some in-class assignments are described. Also, an outcome in terms of student-centered learning and uniformity amongst the separate sections is discussed.

ABET assessment of student initiated interdisciplinary senior capstone project

In most capstone engineering projects, it is not unlikely to have collaborative work between engineers of different disciplines, but few projects incorporate the work of disciplines outside of the engineering school. This paper is a case study of a student initiated capstone engineering project which incorporates collaborative work between engineering and fine art students. The problem statement of the proposed project was “to build, fabricate, test and install an interactive outdoor sculpture for the Binghamton University campus.” The design process of the project will be reviewed at different stages: from artistic design, through structural analysis, to construction of a scale section of the sculpture for testing purposes. This paper will describe the collaboration of designers (artists, engineers) for whom the practice of “design” is different. A comparison will be made between previous interdisciplinary projects. In addition, the ABET assessment of this interdisciplinary project will be presented.

Teaching concepts in fuzzy logic using low cost robots, PDAs, and custom software

Fuzzy logic is a topic traditionally taught in artificial intelligence, machine learning, and robotics courses. Students receive the necessary mathematical and theoretical foundation in lecture format. The final learning experience may require that students create and code their own fuzzy logic application that solves a real world problem. This can be an issue when the target is a bioengineering course that introduces classical control theory, fuzzy logic, neural networks, genetic algorithms and genetic programming through the use of a low cost robot, personal digital assistant (PDA) handheld computer, and custom PDA software. In this course, the concepts and theories discussed in lecture are reinforced and extended in a corresponding laboratory through the use of wireless robots and PDAs. Fuzzy logic libraries and software modules for laptops and desktop computers are readily available, however, when it comes to handheld computers no such libraries exist. Students are able to spend more time experimenting with different fuzzy logic controllers when a custom fuzzy logic library and PDA graphical user interface are utilized. In this paper we introduce and discuss a unique low cost wireless robot, a custom fuzzy logic library, a custom fuzzy logic GUI for the PDA, and the implementation results for the fuzzy logic section in a newly created bioengineering course. Diagnostic and summative assessment in the form of a pre-test and post-test was administered for each section of the course, however, only the results for the fuzzy logic section will be provided.

The role of active learning through laboratory experimentation pertaining to memory retention in first-year engineering programs

Retention of material taught to students can be affected by their active participation in a laboratory. The purpose of this active learning memory retention study is to determine how learning, varying active or passive participation, affects memory retention. This paper uses a weekly laboratory in a first-year engineering course as an example. We compare three modes of presentation of material: demonstration, interactive programs, and hands-on execution. Results show that, based on student performance on examination scores, demonstration alone is not as effective as simulation or hands-on labs. However, we found very little difference between the results for simulation and hands-on labs.