515.655.3VL - Metal Additive Manufacturing
Description
Additive Manufacturing (AM), also known colloquially as 3D Printing, is a disruptive technology that has received significant attention in recent years in both the popular press and the manufacturing industry. While the current and potential future applications for this technology, especially for mission-critical metal parts, are impressive and imaginative, the full potential for metal AM has not been realized due to current limitations and a lack of full understanding of metal AM processes. In this class we will cover (1) the current state-of-the-art of AM; (2) the production steps necessary to manufacture AM parts; and (3) the closely linked topics of AM materials and AM processes. While non-metal AM materials such as polymers, composites, and ceramics will be included, the primary focus will be on metal materials fabricated with laser powder bed fusion processes. Specific topics covered will include conventional vs. AM materials, meltpool phenomena including solidification, kinetics and solid-state kinetics, post-process thermal treatments, the process-properties relationship, in-situ process sensing, indirect process measurement methods and process modeling. Recent implementations of metal additive manufacturing, such as those in the aerospace and health care industries, will be presented extensively throughout the class as study cases. Popular press articles and technical papers on AM will be reviewed and discussed. Students taking this class will be expected to participate actively and bring to the class real or potential applications of AM in their workplaces.
Instructor
Carly Mayhood
Course Structure
The course is divided into weekly modules that include one or more topics covered in class.
Weekly Quizzes: There will be short weekly quizzes that are based on the previous class’ lecture and discussion. These quizzes will be taken at the beginning of class and corrected immediately after being taken. They will not be counted as part of the final grade and are only used as a measurement of student progress.
Homework and Class Participation: There will be assigned homework assignments that are due at the beginning of each class. Some homework will be written assignments or problems that should be turned in at the beginning of class. Other homework will be background readings as preparation for in-class discussion. Homework solutions will be discussed in class. Written homework must be submitted via CANVAS. Homework not by the beginning of the next class will received a grade of zero. Homework should be legible and well-written with correct grammar and punctuation. The lowest score homework will not be counted. Absent students must still submit homework to the instructor via Blackboard, before the scheduled start of class, in order to receive credit. Even though this is a virtual live course, this class will have a heavy emphasis on in-class discussion and student participation, and as such students are expected to attend every class. If you have particular conflicts or situations please discuss them individually with the instructor. Homework counts for 30% and attendance/participation count for 10% of the final grade.
Midterm Examination: The midterm examination will be both qualitative (consisting of short answer questions) and quantitative calculations that will demonstrate mastery of all of the topics covered in the first part of the semester. Representative example questions of the style contained in the final exam will be assigned as homework throughout the semester. The exam will be a take home exam due and submitted into Canvas by 7:00 pm on 15 March. Students may not consult or work with others on the exam. This exam counts for 30% of the final grade.
Final Project: Each student will perform in-depth research on one AM topic that we have covered in class, or a closely related AM topic. Each student will give a ten-minute presentation of their work on the final day of class. Students who perform exceptional research on their topic will be encouraged to work with the instructors to develop a journal-worthy publication. Your topic must be approved in advance by the instructor. There are several milestones throughout the semester to help keep you on schedule:
15 March Topic selection
5 April A bibliography with at least five sources due
19 April A detailed outline of your presentation with draft findings due
3 May Presentations
Your instructor will provide feedback for each of the milestones. This project will account for 30% of the final grade.
Course Topics
- Review of Traditional Manufacturing Processes
- Basic AM Principles, Terminology, Process Advantages and Limitations
- The Hype and Reality of AM
- The Seven AM Processes
- AM Process Flow, Support Structures, File Formats, Design for AM, AM Part Suitability, Post Processing
- AM Powder, Powder Packing, and Powder Spreading
- Facility requirements and the Economics of AM/3DP part production
- Material Science and Thermodynamics Review
- Welding Metallurgy Principles and why AM is not welding
- Melt Pool Dynamics and Effects of Process Parameters on Microstructures
- AM Process Phenomena, Laser/Material Interactions, Defects
- AM Material Properties and Structure
- Residual Stress
- Standard and Non-Standard Materials (including ceramics and composites)
- In-situ Sensing and System Performance
- Non-Destructive Evaluation
- AM Standards, Qualification, and Certification
- AM Process Models and Physics-Based Models
Course Goals
Course Goal:
To understand the complete metal additive manufacturing production cycle, from design through production to final part realization. Particularly, to apply fundamental material science and mechanical engineering concepts in the understanding of the complex process and material facets of metal laser powder bed fusion.
Course Objectives:
- To be able to properly distinguish between the hype and realities of additive manufacturing
- To use AM terminology properly
- To have a practical and broad understanding of additive manufacturing and the complete additive manufacturing production process, including understanding the differences between traditional manufacturing design/processes and AM processes/design.
- To apply fundamental material science and mechanical engineering concepts in the understanding of the complex process and materials facets of metal laser powder bed fusion
- Focus on the laser powder bed fusion and directed energy deposition processes
- To understand the role and importance of standards in the additive manufacturing industry
Textbooks
None
Other Materials & Online Resources
The following textbooks are optional, but contain useful information for those who want to explore further.
Additive Manufacturing Technologies: 3D Printing, Rapid Prototyping, and Direct Digital Manufacturing (2015, Springer) by Ian Gibson, David Rosen, and Brent Stucker, ISBN 978-1-4939-2112-6. The information in this textbook is uneven, and the presentation value is not the best, but it does contain some good detailed information on the seven different AM processes.
Welding Metallurgy and Weldability (2015, Wiley) by John C. Lippold, ISBN 978-1-118-23070-1. This textbook focuses on welding, but many of the process and materials concepts presented here have applicability in metal additive manufacturing.
Fabricated – The New World of 3D Printing (2013, Wiley) by Hod Lipson and Melba Kurman, ISBN 978-1-118-35063-8. This is a popular press coffee table book on additive manufacturing.
Required Software
None
Student Coursework Requirements
Homework | 30% |
Attendance and Class Participation | 10% |
Midterm Examination | 30% |
Final Project | 30% |
Total | 100% |
Grading Policy
This class uses the EP +/- grading system (see “Grading System”, Graduate Programs catalog).
100-98 = A+
97-94 = A
93-90 = A−
89-87 = B+
86-83 = B
82-80 = B−
79-77 = C+
76-73 = C
72-70 = C−
69-67 = D+
66-63 = D
<63 = F
Course Evaluation
Weekly Quizzes: There will be short weekly quizzes that are based on the previous class’ lecture and discussion. These quizzes will be taken at the beginning of class and corrected immediately after being taken. They will not be counted as part of the final grade and are only used as a measurement of student progress.
Homework and Class Participation: There will be assigned homework assignments that are due at the beginning of each class. Some homework will be written assignments or problems that should be turned in at the beginning of class. Other homework will be background readings as preparation for in-class discussion. Homework solutions will be discussed in class. Written homework must be submitted via Blackboard. Homework not by the beginning of the next class will received a grade of zero. Homework should be legible and well-written with correct grammar and punctuation. The lowest score homework will not be counted. Absent students must still submit homework to the instructor via Blackboard, before the scheduled start of class, in order to receive credit. Even though this is a virtual live course, this class will have a heavy emphasis on in-class discussion and student participation, and as such students are expected to attend every class. If you have particular conflicts or situations please discuss them individually with the instructor. Homework counts for 30% and attendance/participation count for 10% of the final grade.
Midterm Examination: The midterm examination will be both qualitative (consisting of short answer questions) and quantitative calculations that will demonstrate mastery of all of the topics covered in the first part of the semester. Representative example questions of the style contained in the final exam will be assigned as homework throughout the semester. The exam will be a take home exam due and submitted into Canvas by 7:00 pm on 15 March. Students may not consult or work with others on the exam. This exam counts for 30% of the final grade.
Final Project: Each student will perform in-depth research on one AM topic that we have covered in class, or a closely related AM topic. Each student will give a ten-minute presentation of their work on the final day of class. Students who perform exceptional research on their topic will be encouraged to work with the instructors to develop a journal-worthy publication. Your topic must be approved in advance by the instructor. There are several milestones throughout the semester to help keep you on schedule:
15 March Topic selection
5 April A bibliography with at least five sources due
19 April A detailed outline of your presentation with draft findings due
3 May Presentations
Your instructor will provide feedback for each of the milestones. This project will account for 30% of the final grade.
Course Policies
Students are expected to do their own work. You may certainly consult with your fellow students and discuss your general ideas but your submitted assignments should be your own product. All work should be well-written, legible, neat & well-organized, and free of spelling and grammatical errors. You may (and are encouraged!) to consult other sources but these should be properly referenced in your submissions. Work should be submitted on-time unless other arrangements have been discussed with the instructor. Generally, late-submitted work will not be eligible for full credit. Students are expected to attend class and participate actively.
Academic Policies
Deadlines for Adding, Dropping and Withdrawing from Courses
Students may add a course up to one week after the start of the term for that particular course. Students may drop courses according to the drop deadlines outlined in the EP academic calendar (https://ep.jhu.edu/student-services/academic-calendar/). Between the 6th week of the class and prior to the final withdrawal deadline, a student may withdraw from a course with a W on their academic record. A record of the course will remain on the academic record with a W appearing in the grade column to indicate that the student registered and withdrew from the course.
Academic Misconduct Policy
All students are required to read, know, and comply with the Johns Hopkins University Krieger School of Arts and Sciences (KSAS) / Whiting School of Engineering (WSE) Procedures for Handling Allegations of Misconduct by Full-Time and Part-Time Graduate Students.
This policy prohibits academic misconduct, including but not limited to the following: cheating or facilitating cheating; plagiarism; reuse of assignments; unauthorized collaboration; alteration of graded assignments; and unfair competition. Course materials (old assignments, texts, or examinations, etc.) should not be shared unless authorized by the course instructor. Any questions related to this policy should be directed to EP’s academic integrity officer at ep-academic-integrity@jhu.edu.
Students with Disabilities - Accommodations and Accessibility
Johns Hopkins University values diversity and inclusion. We are committed to providing welcoming, equitable, and accessible educational experiences for all students. Students with disabilities (including those with psychological conditions, medical conditions and temporary disabilities) can request accommodations for this course by providing an Accommodation Letter issued by Student Disability Services (SDS). Please request accommodations for this course as early as possible to provide time for effective communication and arrangements.
For further information or to start the process of requesting accommodations, please contact Student Disability Services at Engineering for Professionals, ep-disability-svcs@jhu.edu.
Student Conduct Code
The fundamental purpose of the JHU regulation of student conduct is to promote and to protect the health, safety, welfare, property, and rights of all members of the University community as well as to promote the orderly operation of the University and to safeguard its property and facilities. As members of the University community, students accept certain responsibilities which support the educational mission and create an environment in which all students are afforded the same opportunity to succeed academically.
For a full description of the code please visit the following website: https://studentaffairs.jhu.edu/policies-guidelines/student-code/
Classroom Climate
JHU is committed to creating a classroom environment that values the diversity of experiences and perspectives that all students bring. Everyone has the right to be treated with dignity and respect. Fostering an inclusive climate is important. Research and experience show that students who interact with peers who are different from themselves learn new things and experience tangible educational outcomes. At no time in this learning process should someone be singled out or treated unequally on the basis of any seen or unseen part of their identity.
If you have concerns in this course about harassment, discrimination, or any unequal treatment, or if you seek accommodations or resources, please reach out to the course instructor directly. Reporting will never impact your course grade. You may also share concerns with your program chair, the Assistant Dean for Diversity and Inclusion, or the Office of Institutional Equity. In handling reports, people will protect your privacy as much as possible, but faculty and staff are required to officially report information for some cases (e.g. sexual harassment).
Course Auditing
When a student enrolls in an EP course with “audit” status, the student must reach an understanding with the instructor as to what is required to earn the “audit.” If the student does not meet those expectations, the instructor must notify the EP Registration Team [EP-Registration@exchange.johnshopkins.edu] in order for the student to be retroactively dropped or withdrawn from the course (depending on when the "audit" was requested and in accordance with EP registration deadlines). All lecture content will remain accessible to auditing students, but access to all other course material is left to the discretion of the instructor.