(NEW) During this course, students will locate defects in additively manufactured parts and examine the material around them. Students will begin with the AM processes that produce the defects, then move to radiography and X-ray computed tomography, including scan physics and instrumentation, radiation safety, and artifact diagnosis. Reconstructed volumes will be segmented to demonstrate measurement of porosity and wall thickness. Students will then section, mount, polish, and etch AM alloys to resolve the melt pool boundaries, grain morphology, and solidification substructure that no scan can show. Lack-of-fusion, keyhole, and gas porosity will be classified, and the effects of stress relief, heat treatment, and HIP compared. CT’s resolution and penetration limits, and metallography’s single plane, will be addressed throughout. Laboratory work on ASM’s Nikon XT H 225 ST, in VGSTUDIO MAX, and metallographic preparation for examination at the microscope alternates with lectures. Participants are encouraged to bring their own samples.
This is the course you need if you inspect AM parts and want to know what each method can and cannot tell you.
Content is drawn from the ASM Handbook series, including Volume 17: Nondestructive Evaluation of Materials, and Volume 24A: Additive Manufacturing Design and Applications.
Who Should Attend Class:
- Metallographers and
Technicians
- Quality, NDT, and Inspection
Personnel
- Additive Manufacturing
Engineers and Process Developers
- Design Engineers who specify
inspection requirements
- Laboratory Managers
- Powder producers and
feedstock quality personnel
- Anyone responsible for
characterizing or accepting additively manufactured parts
Learning Objectives:
Upon completion of this course, you will be able to:
- Select a CT system class and
scan parameters for the inspection question at hand
- Distinguish scan artifacts
from genuine features of the part
- Prepare AM specimens while
preserving porosity and edges
- Quantify porosity from microscopic
examination
- Select the proper etchant and
identify AM microstructures and defects: melt pools, columnar grains,
lack-of-fusion, keyhole, and gas porosity
- Relate as-built and
post-processed microstructures to thermal history
- Recognize the limits of CT
and metallography
Recommended Prerequisites:
Prior metallographic experience, or completion of an introductory metallography course, is recommended. A background in sample preparation, heat treating, or metallurgy will enhance understanding of the presented material. No prior radiography or computed tomography experience is required.
Course Outline:
1. Lecture on AM processes and the microstructures they produce
2. Lecture on radiography, CT physics, instrumentation, radiation safety, and artifact diagnosis
3. CT scanning of an AM specimen on site, if dimensions allow, or discussion of limitations and demo of CT scan
4. Segmentation and analysis of the reconstructed volume to measure porosity and wall thickness
5. Sectioning, mounting, polishing, and etching of AM specimens
6. Interpretation of AM microstructures and defects, and the effects of post-processing
Continuing Education Units: 2.0