Shedding new light on laser additive manufacturing

Additive manufacturing (AM, also known as 3D printing) allows us to create incredibly complex shapes, which would not be possible using traditional manufacturing techniques. However, objects created using AM have different properties from traditional manufacturing routes, which is sometimes a disadvantage.

Laser additive manufacturing (LAM) uses a laser to fuse together metallic, ceramic or other powders into complex 3D shapes, layer by layer. The cooling rates are extremely rapid, and since they are unlike conventional processes we don’t know the optimal conditions to obtain the best properties, delaying the uptake of LAM in the production of safety-critical engineering structures, such as turbine blades, energy storage and biomedical devices. We need a method to see inside the process of LAM to better understand and optimise the laser-matter interaction and powder consolidation mechanisms.

Based in the Research Complex at Harwell, a team of researchers have worked with scientists at I12, the Joint Engineering Environment Processing (JEEP) beamline and the Central Laser Facility to build a laser additive manufacturing machine which operates on a beamline, allowing you to see into the heart of the process, revealing the underlying physical phenomena during LAM.

>Read more on the Diamond Light Source website

Picture: The Additive Manufacturing Team from the Research Complex at Harwell on the Joint Engineering Environment Processing (JEEP, I12) beamline. The Laser Additive Manufacturing Process Replicator (or LAMPR) on the right is used to reveal the underlying physical phenomena during LAM.

The early bird got to fly: Archaeopteryx was an active flyer

Was Archaeopteryx capable of flying, and if so, how?

The question of whether the Late Jurassic dino-bird Archaeopteryx was an elaborately feathered ground dweller, a glider, or an active flyer has fascinated palaeontologists for decades. Valuable new information obtained with state-of-the-art synchrotron microtomography at the ESRF, the European Synchrotron (Grenoble, France), allowed an international team of scientists to answer this question in Nature Communications. The wing bones of Archaeopteryx were shaped for incidental active flight, but not for the advanced style of flying mastered by today’s birds.

Was Archaeopteryx capable of flying, and if so, how? Although it is common knowledge that modern-day birds descended from extinct dinosaurs, many questions on their early evolution and the development of avian flight remain unanswered. Traditional research methods have thus far been unable to answer the question whether Archaeopteryx flew or not. Using synchrotron microtomography at the ESRF’s beamline ID19 to probe inside Archaeopteryx fossils, an international team of scientists from the ESRF, Palacký University, Czech Republic, CNRS and Sorbonne University, France, Uppsala University, Sweden, and Bürgermeister-Müller-Museum Solnhofen, Germany, shed new light on this earliest of birds.

>Read more on the European Synchrotron website

Image: The Munich specimen of the transitional bird Archaeopteryx. It preserves a partial skull (top left), shoulder girdle and both wings slightly raised up (most left to center left), the ribcage (center), and the pelvic girdle and both legs in a “cycling” posture (right); all connected by the vertebral column from the neck (top left, under the skull) to the tip of the tail (most right). Imprints of its wing feathers are visible radiating from below the shoulder and vague imprints of the tail plumage can be recognised extending from the tip of the tail.
Credits: ESRF/Pascal Goetgheluck

Examining the crystallisation during additive biomanufacturing

A research group from the University of Manchester has used wide-angle X-ray diffraction (XRD) in one of the first studies to investigate the evolution of crystallinity and crystal orientation in polycaprolactone (PCL) during 3D printing.

The team has developed a new extrusion-based printing machine, the Plasma-assisted Bioextrusion System (PABS). Extrusion-based techniques are widely used due to their versatility and simplicity, and their ability to print a range of materials in a cell-friendly environment, with high precision. PABS uses a novel approach for biomanufacturing and tissue engineering, combining screw-assisted extrusion, pressure-assisted extrusion and plasma jetting.

>Read more on the Diamond Light Source website

Figure: Conceptual material transition from extrusion-based filament printing to the partial replacement of a knee joint via 3D scaffolding.
Credit: Fengyuan Liu, Wajira Mirihanage, Paulo Bartolo, Medical Engineering Research Centre, the University of Manchester

Research on the teeth of a prehistoric fetus

It gives us information about the last months of a mother and child, who lived 27.000 years BP.

Fossil records enable a detailed reconstruction of our planet’s history and of the evolution of our species. Dental enamel is a sort of biological archive that constantly tracks periods of good and bad health, while forming. Prenatal enamel, which grows during intrauterine life, reports the mother’s history as well.

We have studied fossil records found in the “Ostuni 1” burial site, discovered in Santa Maria di Agnano in Puglia in 1991 by Donato Coppola (Università di Bari, Italy) and dated back over 27,000 years. More specifically, we were interested in the teeth of a fetus found in the pelvic area of the skeleton of a young girl. By analysing the still forming teeth of the baby, it has been possible to obtain information about the health condition of the mother during the last months of pregnancy, to establish the gestational age of the fetus, and also to identify some specificities of the embryonal development. For the first time, it has been possible to reconstruct life and death of an ancient fetus and, at the same time, to shed light on its mother’s health.

Three still-forming incisors, belonging to the fetus, have been visualized and analyzed by means of X-ray microtomography at Elettra. The preliminary analysis on a portion of the fetal mandible, realized at the TomoLab laboratory allowed us to study the still-forming incisor contained within it (see Fig. 1). Thanks to the unique properties of synchrotron radiation and using a specifically-developed methodology, a high resolution 3D analysis has been carried out on the teeth at the SYRMEP beamline. This approach, allowed us to carry out a virtual histological analysis of the precious fossil teeth, revealing the finest structures of the dental enamel in a non-destructive way.

>Read more on the Elettra website

Image:  Pseudo color rendering of the virtual histological section of the Ostuni1b’s upper left deciduous central incisor. The corresponding CT scan has been acquired at the SYRMEP beamline in phase-contras mode.

A first look at how miniscule bubbles affect the texture of noodles

The texture of a noodle is a remarkably complicated thing. When you bite into a spoonful of ramen noodles, you expect a bit of springiness (or a resistance to your bite) on the outside and a pleasantly soft give on the interior. These variations are so tiny as to be often overlooked, but they matter to noodle quality.

There are many factors in play in making a good noodle. For a wheat noodle, the structure of the gluten affects the overall quality. How a noodle dough is stretched, folded, and rolled out matters. And in between all of this, there are miniscule air bubbles that are part of the mix and influence texture.

Until recently, no one had ever looked at the bubbles in noodle dough.

“There was absolutely nothing in the literature indicating that the bubbles were there or that they were important at all. We did have some indirect evidence for bubbles from our ultrasonic experiments, but CLS (Canadian Light Source) microtomography was in some ways a hail Mary experiment: OK, let’s just sheet some dough and see what we find,” said Martin Scanlon, U of M professor in the Faculty of Agriculture and Food Sciences, and the project’s lead researcher.

>Read more on the Canadian Light Source website

 

SLAC scientists investigate how metal 3D printing can avoid producing flawed parts

The goal of these X-ray studies is to find ways to improve manufacturing of specialized metal parts for the aerospace, aircraft, automotive and healthcare industries.

Scientists at the Department of Energy’s SLAC National Accelerator Laboratory are using X-ray light to observe and understand how the process of making metal parts using three-dimensional (3-D) printing can leave flaws in the finished product – and discover how those flaws can be prevented. The studies aim to help manufacturers build more reliable parts on the spot – whether in a factory, on a ship or plane, or even remotely in space – and do it more efficiently, without needing to store thousands of extra parts.

The work is taking place at the lab’s Stanford Synchrotron Radiation Lightsource (SSRL) in collaboration with scientists from the DOE’s Lawrence Livermore National Laboratory and Ames Laboratory.

The 3-D printing process, also known as additive manufacturing, builds solid, three-dimensional objects from a computer model by adding material layer by layer. The use of plastics and polymers in 3-D printing has advanced rapidly, but 3-D printing with metals for industrial purposes has been more challenging to sort out.

>Read more on the SSRL website

Picture: SLAC staff scientist Johanna Nelson Weker, front, leads a study on metal 3-D printing at SLAC’s Stanford Synchrotron Radiation Lightsource with researchers Andrew Kiss and Nick Calta, back.
Credit: Dawn Harmer/SLAC

 

How metal 3-D printing can avoid producing flawed parts

The goal of these X-ray studies is to find ways to improve manufacturing of specialized metal parts for the aerospace, aircraft, automotive and healthcare industries.

Scientists at the Department of Energy’s SLAC National Accelerator Laboratory are using X-ray light to observe and understand how the process of making metal parts using three-dimensional (3-D) printing can leave flaws in the finished product – and discover how those flaws can be prevented. The studies aim to help manufacturers build more reliable parts on the spot – whether in a factory, on a ship or plane, or even remotely in space – and do it more efficiently, without needing to store thousands of extra parts.

The work is taking place at the lab’s Stanford Synchrotron Radiation Lightsource (SSRL) in collaboration with scientists from the DOE’s Lawrence Livermore National Laboratory and Ames Laboratory.

The 3-D printing process, also known as additive manufacturing, builds solid, three-dimensional objects from a computer model by adding material layer by layer. The use of plastics and polymers in 3-D printing has advanced rapidly, but 3-D printing with metals for industrial purposes has been more challenging to sort out.

“With 3-D printing, you can make parts with very complex geometries that are not accessible for casting like regular metal parts,” says SLAC staff scientist Johanna Nelson Weker, who is leading the project. “Theoretically, it can be a quick turnaround – simply design, send, print from a remote location. But we’re not there yet. We still need to figure out all of the parameters involved in making solid, strong parts.”

>Read more on the Stanford Synchrotron Radiation Lightsource website

Image: SLAC staff scientist Johanna Nelson Weker, front, leads a study on metal 3-D printing at SLAC’s Stanford Synchrotron Radiation Lightsource with researchers Andrew Kiss and Nick Calta, back.
Credit: Dawn Harmer/SLAC

Natalie Larson awarded

She received the Neville B. Smith Student Poster Prize

Natalie Larson, a current ALS doctoral fellow from UC Santa Barbara, won the first prize Neville B. Smith Student Poster Award at the 2017 ALS User Meeting. Larson’s winning poster—”In-situ x-ray computed tomography of defect evolution during polymer impregnation and pyrolysis processing of ceramic matrix composites”—featured the first two big in situ experiments she performed at Beamline 8.3.2.

Larson has been an ALS user since 2014 and became a doctoral fellow in 2016. She’ll continue at the ALS for about another year through a National Science Foundation fellowship that will see her through the end of her PhD. The primary focus of her work is developing high-temperature ceramic matrix composites (CMCs) for more efficient jet engines. Larson works with Beamline Scientists Dula Parkinson and Alastair MacDowell and Project Scientist Harold Barnard on developing experiments for in situ x-ray computed tomography experiments to observe 3D real-time defect formation in CMCs.

 

3D structure of a molecular scaffold with role in cancer

The research team is looking at ways of targeting parts of the scaffold molecule critical for its function

Melbourne researchers have used the Australian Synchrotron to produce the first three-dimensional structure of a molecular scaffold, known to play a critical role in the development and spread of aggressive breast, colon and pancreatic cancer.
Armed with the structure, the research team is looking at ways of targeting parts of the scaffold molecule critical for its function. They hope the research will lead to novel strategies to target cancer.

The research was the result of a long-standing collaboration between Walter and Eliza Hall Institute (WEHI) researchers Dr Onisha Patel and Dr Isabelle Lucet and Monash University Biomedical Research Institute researcher Professor Roger Daly.

Dr Santosh Panjikar, a macromolecular crystallographer at the Australian Synchrotron and Dr Michael Griffin from Bio21 Institute at the University of Melbourne made important contributions to the study, which was published in the journal Nature Communications.

Translation of ‘Hidden’ Information Reveals Chemistry in Action

New method allows on-the-fly analysis of how catalysts change during reactions, providing crucial information for improving performance.

Chemistry is a complex dance of atoms. Subtle shifts in position and shuffles of electrons break and remake chemical bonds as participants change partners. Catalysts are like molecular matchmakers that make it easier for sometimes-reluctant partners to interact.

Now scientists have a way to capture the details of chemistry choreography as it happens. The method—which relies on computers that have learned to recognize hidden signs of the steps—should help them improve the performance of catalysts to drive reactions toward desired products faster.

The method—developed by an interdisciplinary team of chemists, computational scientists, and physicists at the U.S. Department of Energy’s Brookhaven National Laboratory and Stony Brook University—is described in a new paper published in the Journal of Physical Chemistry Letters. The paper demonstrates how the team used neural networks and machine learning to teach computers to decode previously inaccessible information from x-ray data, and then used that data to decipher 3D nanoscale structures.

Scientist combines medicine and engineering to repair a damaged heart

Regenerating heart muscle tissue using a 3D printer – once the stuff of Star Trek science fiction – now appears to be firmly in the realm of the possible.

The combination of the Canadian Light Source synchrotron’s unique biomedical imaging and therapy (BMIT) beamline and the vision of a multi-discipline researcher from the University of Saskatchewan in confirming fiction as fact was published in the September issue of Tissue Engineering, one of the leading journals in this emerging global research field of tissue regeneration.

U of S researcher Mohammad Izadifar says he is combining medicine and engineering to develop ways to repair a damaged heart. “The problem is the heart cannot repair itself once it is damaged due to a heart attack.” he explained.

Izadifar has conducted his research out of three places on campus – the College of Engineering, the CLS and the College of Medicine where he has been certified in doing open heart surgery on rats, having trained in all the ethical protocols related to these research animals.

Molecular Movie

Researchers Create Molecular Movie of Virus Preparing to Infect Healthy Cells

With SLAC’s X-ray laser, scientists captured a virus changing shape and rearranging its genome to invade a cell.

A research team has created for the first time a movie with nanoscale resolution of the three-dimensional changes a virus undergoes as it prepares to infect a healthy cell. The scientists analyzed thousands of individual snapshots from intense X-ray flashes, capturing the process in an experiment at the Department of Energy’s SLAC National Accelerator Laboratory.

>Read More

Growing a better polio vaccine

Researchers use plants as factories to produce a safer polio vaccine

Successful vaccination campaigns have reduced the number of polio cases by over 99% in the last several decades. However, producing the vaccines entails maintaining a large stock of poliovirus, raising the risk that the disease may accidentally be reintroduced.
Outbreaks can also occur due to mutation of the weakened poliovirus used in the oral vaccine. In addition, the oral vaccine has to be stored at cold temperatures. To address these shortcomings, an international team of researchers across the UK has engineered plants that produce virus-like particles derived from poliovirus, which can serve as a vaccine.
They report the success of this approach in a paper appearing in Nature Communications. The team confirmed the structure of the virus-like particles by cryo-electron microscopy at Diamond Light Source’s Electron Bio-Imaging Centre (eBIC) and showed that the particles effectively protected mice from infection with poliovirus. This proof-of-principle study demonstrates that a safe, effective polio vaccine can be produced in plants and raises the possibility of using the same approach to tackle other viruses.

Diving into magnets

First-time 3D imaging of internal magnetic patterns

Magnets are found in motors, in energy production and in data storage. A deeper understanding of the basic properties of magnetic materials could therefore impact our everyday technology. A study by scientists at the Paul Scherrer Institute PSI in Switzerland, the ETH Zurich and the University of Glasgow has the potential to further this understanding.

The researchers have for the first time made visible the directions of the magnetisation inside an object thicker than ever before in 3D and down to details ten thousand times smaller than a millimetre (100 nanometres). They were able to map the three dimensional arrangement of the magnetic moments. These can be thought of as tiny magnetic compass needles inside the material that collectively define its magnetic structure. The scientists achieved their visualisation inside a gadolinium-cobalt magnet using an experimental imaging technique called hard X-ray magnetic tomography which was developed at PSI. The result revealed intriguing intertwining patterns and, within them, so-called Bloch points.

At a Bloch point, the magnetic needles abruptly change their direction. Bloch points were predicted theoretically in 1965 but have only now been observed directly with these new measurements. The researchers published their study in the renowned scientific journal Nature.

>Read More on the PSI website

Image: A vertical slice of the internal magnetic structure of a sample section. The sample is 0.005 millimetres (5 micrometres) in diameter and the section shown here is 0.0036 millimetres (3.6 micrometres) high. The internal magnetic structure is represented by arrows for a vertical slice within it. In addition, the colour of the arrows indicate whether they are pointing towards (orange) or away from the viewer (purple). (Graphics: Paul Scherrer Institute/Claire Donnelly)

Photonic structure of white beetle wing scales: optimized by evolution

They have developed a complicated three-dimensional photonic structure on their wing scales in order to efficiently reflect white light.

At the same time, this structure is very porous and is confined within a thin layer of about 10  µm, about one fifth of the thickness of ordinary white paper, which makes it very light and therefore advantageous to fly.

Researchers of the University of Fribourg and their collaborators wanted to understand how this fascinating structure is optimized, for which they needed a faithful 3D image. However, conventional microscopy techniques providing enough spatial resolution such as electron microscopy required the sample to be cut for imaging consecutive slices, causing damage of the structure during the process.

>Read More on the PSI website

Image: Cyphochilus white beetle source: PSI