AC 2007-1906: MATERIALS SELECTION EXERCISES BASED ON CURRENT EVENTS

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Issues relating to a wide range of consumer and industrial products appear in newspaper articles and on a variety of television shows, every day. These exercises were developed to give engineering students a societal and global perspective on technical problems important to the general public. Beginning with the concerns brought to light in a newspaper article, students employed their knowledge of material selection methodology and engineering principles to investigate the implication of the choice of materials. The CES EduPack 2005 Materials Selection software is utilized as the primary tool to provide the technical support for their analysis, conclusions, and comments. The general format of the exercises presented here includes the task outline, materials selection techniques, specifications for oral and written assignments, and the in-class activities and discussions. The exercises were implemented based on two newspaper headlines, “Marines Say Body Armor Too Heavy” and “Mission: Design Better (Space) Gloves”. Samples of student work highlighted the different skill levels of achieved by students applying the techniques of material selection, as well as, the unique perspective of individual students to solving and/or commenting on these open end problems. With their ability to share results through presentations, students were teaching students. The peer evaluations developed a positive classroom environment promoting creativity and improvement in the technical content of subsequent projects. Students began to see the connections between the public concerns and opinions, and their role as engineers in the design, development or manufacture of a product. The possibilities for media examples are endless and provide students and faculty with a wide range of ideas to promote interest, motivation and a learning opportunity for today’s engineering student. Introduction Do we take the material of a product for granted, or do we look at a product and remember what it used to be made of? Do we ever stop to think about what our daily lives would be like if scientists hadn’t explored the properties of silicon or polymers? Do we realize materials and the importance of materials selection touches our lives everyday through the mass media? Most technically oriented people, including engineering students and faculty, enjoy watching P ge 12038.2 Discovery Channel TM and History Channel TM television shows like Modern Marvels, Engineering Disasters, and Extreme Engineering or reading trade magazines associated with their industry or hobbies, or hitting the favorite technical sites on the web. Often transportation accidents, infrastructure failures, accidental injuries or deaths due to use (or misuse) of products, consumer recalls are covered by in the national and local news on television and in print. Engineers usually take notice, and with their technical training, tend to ‘read between the lines’ of article or report written for the general public. With a ‘keen eye’ and a passion for materials science problems, an instructor can identify public interest stories from the mass media and develop instructional exercises in the area of materials selection. Current events are on the student’s ‘radar’ and immediately generate interest, without obviously favoring someone with a specific academic or personal background. The event or topic selected provides the catalyst for implementing the methodology pertinent to materials selection yet allows the students to take creative approaches to developing their ‘solutions’. The proposed exercises will attempt to add technical depth and perspective to the student’s reaction to the event, versus just opinions based on personal background and life experiences. Development and Implementation In the context of a materials selection course, current events were used generate student interest and provide the ‘good examples’ for developing exercises and assignments. Two exercises will be presented here, the first having an open ended approach with minimal guidance in the problem statement and assignment deliverables, and the second being a more focused approach with significant amount of guidance in the problem statement and specific requirements for assessment. At the instructor’s home institution, the catalog description for Special TopicsMaterials Selection and Engineering Design and Manufacturing is as follows. “The course will develop a systematic approach for the development of a new idea or product and facilitate the continuous improvement processes for products currently on the market. The approach is based on evaluating open-ended design problems with respect to the interrelationship between material, shape, function and processes used to produce a variety of products. In the course, the design process and engineering materials and their properties will be explored using the P ge 12038.3 materials selection charts and the CES Materials Selection software. Case studies and team projects will focus on materials selection and multiple constraints, the factors involved in materials processing and design, and the use of data sources. The students completing this course will have useful solutions to standard problems in industry and a working knowledge of the materials selection software. The methods of assessing students include homework, quizzes, a midterm exam, design project report(s) and a final exam.“ 3 cr. The students were required to have the following text, software and ancillary materials. Text – Ashby, Michael F., Materials Selection in Mechanical Design, Third Edition, Elsevier Butterworth Heinemann © 2005 Software CES EDUPack 2005; Virtual Classroom account for the course; memory stick The participants in this course were part-time Masters’ Degree students, who are young, working professionals looking to improve their engineering skills to better compete in the workplace. Students have backgrounds in mechanical or industrial engineering and work as engineers in the areas of production support, test and project management. Only 1-3 years past graduation with their Bachelors’ degree and significant entry level experience at their companies, these students are eager learners. For most students, a Master’s Degree will be their highest level of technical education attained. It is noted here that upper level undergraduates, who have completed courses in design, materials, manufacturing processes and mechanics of materials, fulfill the prerequisites to meet the outcomes related to the example exercises. The general set of outcomes for the course incorporates the philosophy and methodology of materials selection, the proficiency with the CES EDUPack software, and ability to apply the design process to solve real world problems. The learning outcomes develop knowledge and skills to select materials and processes, and determine a configuration to meet the need of an engineering problem and its design constraints defined by the consumer and/or industry. Student will explore the following ideas in engineering design: 1) sensible translation of the design requirements into material constraints and design objectives, 2) ‘good judgment’ in the positioning of selection lines on the materials selection charts (i.e. use of CES EDUPack software) and, 3) reflect on the implications of the material(s) selected for the ‘product’. P ge 12038.4 The philosophy and methodology adopted throughout the Materials Selection and Engineering Design and Manufacturing course, is that presented in the text by Michael Ashby, Materials Selection in Mechanical Design, Third Edition. The exercises propose using the “Ashby’s philosophy” outlined in Figure 1. Strategy for Materials Selection 1 All materials Translate design requirements Screen using constraints Rank using objective Seek supporting information FINAL MATERIAL CHOICE Figure 1. ‘Ashby’s philosophy’ for materials selection (Phrase coined by the students) From the point of view of the instructor, it is critical to emphasize the selection process itself and encourage students to buy into the “Ashby philosophy” and be open-minded with their results. Proper technical justification must be encouraged and the degree of subjectivity in the solutions for the final choice of materials must be discussed. The CES EduPack 2005 Materials Selection software is utilized as the primary tool to provide the technical support for the analysis, conclusions, and comments. Often, each student would be assigned a different textbook example to work out in detail, and then present it to the class for discussion. Students taught students how best to use the software. The CES EDUPack 2005 materials selection software used to explore several topics presented in Ashby text and highlighted as follows: 1) general requirements of the materials universe; 2) use of material selection charts, 3) translation of design problems into engineering terms (or material properties tabulated in the software), 4) derivation and use the material indices, and 5) exploration of the process universe. Advanced concepts including multiple constraints and objectives, and selection of material and shape were studied with the CES software. The examples from the textbook were subsequently incorporated, to some degree, in the design exercises. P ge 12038.5 The focus of the exercises and corresponding assignments is to have students apply materials selection methodology, i.e., “The Ashby Philosophy”, in the design process while solving real world problems. In Figure 2, the Design Table provides the framework for student responses to design problems posed in mainstream news articles. The Design Table: Approach to Materials Selection Function Constraints translation to engineering term Objectives Free variables Figure 2. The Design Table 1 In summary, students began the exercises on common ground, with the design table, a knowledge base in materials selection, and skills using the CES EduPack software.