X-Ray Computed Tomography
Summary of the Technique
X-ray computed tomography (CT) is an advanced imaging technique that provides detailed cross-sectional and three-dimensional views of objects by combining multiple X-ray projections taken from different angles. This method relies on the differential absorption of X-rays by various materials to create contrast in the resulting images, allowing for the examination of internal features without physical dissection.
The process begins with the emission of X-rays through the object of interest onto detectors; these data are then reconstructed computationally to produce slices or full 3D models of the internal structure. X-ray CT is invaluable in fields ranging from medical diagnostics to materials science and engineering, where it enables the non-invasive inspection of component integrity, identification of defects, and analysis of complex internal geometries. Its ability to reveal both the external and internal morphology of objects in high resolution makes it a critical tool for quality control, failure analysis, and research and development initiatives.
X-ray CT scanner in the NMSU NDE Lab:
Waygate Systems Phoenix V|tome|xS 240|180
Applications
X-ray computed tomography (CT) provides deep insights into the internal structures and compositions of a wide variety of materials and objects. Its applications in scientific and engineering fields are vast and varied. Below is an incomplete list of its applications:
Material Science: X-ray CT is instrumental in analyzing the internal microstructure of materials, revealing porosity and phase distributions. It's critical for understanding the properties and performance of metals, polymers, and composites.
Aerospace and Automotive Engineering: In industries where safety and performance are paramount, X-ray CT examines components for manufacturing defects, wear, and fatigue. It ensures that parts meet stringent quality standards and helps in failure analysis to prevent future issues.
Electronics and Semiconductors: It provides insights into the assembly and integrity of complex electronic devices, including circuit boards and semiconductor packages, identifying solder quality, component placement, and hidden defects.
Geology and Paleontology: X-ray CT offers a non-destructive method to study rock formations, mineral deposits, and fossilized remains, revealing details that are often invisible to the naked eye and preserving the integrity of valuable specimens.
Additive Manufacturing (3D Printing): This technology is crucial for validating the internal structure and density of 3D-printed parts, ensuring that they meet design specifications and identifying issues like internal stresses or incomplete fusion.
Archeology and Cultural Heritage Preservation: X-ray CT can penetrate through centuries of dirt and corrosion to uncover the secrets of historical artifacts, from the composition of ancient tools to the construction techniques of historical instruments, without causing any damage.
Forensic Science: In forensic investigations, X-ray CT assists in examining the internal structure of evidence items, providing non-invasive analyses that contribute to understanding crime scenes or accidents.
Agricultural Science and Soil Analysis: It’s used to study plant roots in situ, analyzing root structures, growth patterns, and interactions with the soil without disrupting the plant, offering valuable insights into crop genetics, soil health, and plant physiology.
Inside the NMSU NDE Lab’s X-Ray CT Scanner
Examples of X-ray CT Investigations at NMSU
Roly-Poly
Armadillidium vulgare is commonly referred to as a pillbug, is a terrestrial crustacean notable for its ability to roll into a nearly perfect sphere as a defensive mechanism. These creatures typically measure about 6 to 12 millimeters in length when fully grown. Their unique biology and behavior, along with their adaptation to diverse terrestrial environments, make them intriguing subjects for studies in biomechanics, materials science, and robotics, inspiring innovative applications in design and engineering.
Photo of a pillbug (credit: Martin Cooper)
Reconstructed 3D surface of the pillbug (NMSU NDE lab)
Internal structure of the pillbug (NMSU NDE lab)
Pre-Historic Flightless Bird Fossil
Utilizing the X-ray CT scanner, detailed imaging was obtained of a 55-million-year-old fossilized humerus bone from a flightless bird, on loan to Dr. Houde of NMSU Biology from the Smithsonian. This sophisticated imaging technique enabled Dr. Houde to examine the bone's internal structure non-destructively, ensuring the preservation of this invaluable fossil.
Photo of the bone (credit: Dr. Peter Houde, NMSU)
Reconstructed 3D surface of the bone (NMSU NDE lab)
Internal structure of the bone (NMSU NDE lab)
Forb Seed
Dr. Sara Fuentes-Soriano and graduate student Tiana Nez from NMSU performed detailed investigation of internal structure of forb seeds at NMSU College of Agricultural, Consumer, and Environmental Sciences. This work helped them understand why some seeds fail to germinate.
Reconstructed 3D surface of the forb seed (NMSU NDE lab)
Slice showing the seed embryo (NMSU NDE lab)
3D Printed Stainless Steel Specimens
NMSU Mechanical & Aerospace Engineering PhD student Fidel Baez Avila is working on research into evolution of porosity under tension in additively manufactured stainless steel specimens. This work is performed in collaboration with Dr. David Moore (Sandia National Laboratories).
Photo of dog bone specimen (credit: Fidel Avila, NMSU)
Reconstructed 3D surface of specimen (NMSU NDE lab)
Slice showing internal voids and cracks (NMSU NDE lab)
Interested in Using X-ray CT for your work?
Please contact Dr. Borys Drach (borys@nmsu.edu)
This work was supported by the Army Research Office under award No. W911NF2110138, which funded the acquisition of the X-ray Computed Tomography scanner for the New Mexico State University Non-Destructive Evaluation Laboratory.