A team of Sandia researchers is pioneering the future of superalloy materials by advancing the science behind how those superalloys are made.
As part of Sandia’s nanoscale research, a group of experts specializing in inorganic synthesis and characterization, modeling, and radiation science have designed a radical system of experiments to study the science of creating metal and alloy nanoparticles.
This research has vast implications, says Tina Nenoff (1133). The lightweight, corrosion-resistant materials that the team is creating are needed for weapons casings, gas turbine engines, satellites, aircraft, and power plants.
“What we’re doing is taking a completely new approach to thinking about producing superalloy materials,” Tina says. “We’re using radiation to break down the molecular structure of substances and form nanoparticles — a synthetic approach that is flexible and versatile for making large quantities of superalloy nanoparticle compositions that can’t be easily created otherwise.”
A quick trip down memory lane to the days of high school science class will recall those chapters on material and chemical science defining alloys as a combination of two or more elements, at least one of which is a metal, where the resulting material has metallic properties different — sometimes significantly different — from the properties of its components. For instance, steel is stronger than iron, its primary component.
The Superman of alloys
Superalloys, as the name would imply, stand out from the general population of alloys in the same way Superman would be considered extraordinary compared to the rest of us. These specialized alloys are exceptionally strong, lightweight, and able to withstand extremes that would destroy everyday metals like steel and aluminum.
“These high-performance superalloys are revered for their remarkable mechanical strength, and their resistance to corrosion, oxidation, and deformation at high temperatures,” says Jason Jones (1133).
In the past, the development of these super-alloys has depended on chemical and technological innovations, and been driven mainly by the aerospace and power industries where superalloys are in high demand.
“The method of radiation we’re studying — known as radiolysis — introduces an entirely new area of research into creating alloys and super-alloys through nanoparticle synthesis,” Tina says. “This process holds promise as a universal method of nanoparticle formation. By developing our understanding of the basic material science behind these nanoparticle formations, we’ll then be able to expand our research into other aspects of superalloys, like nickel-based alloys.”
The team is focusing its research on studying the science that happens in the “novel metastable phase spaces” that are not accessible with traditional alloy production methods, such as melting, says Tina. These “phase spaces” are possible points in a given path, or orbit, that represent the motion of a particle over a period of time. Each potential state of that particle’s system corresponds to one unique point in a phase space. Understanding these spaces is important for determining what alloys are created, and how they form.
In the team’s experiments, solvent molecules are combined with molecules or ions and dissolved in water, and the researchers then subject the solution to radiolysis. By varying the reaction conditions and using alcohols as agents to limit particle growth size, the researchers say they have determined through high-resolution transmission electron microscopy that they have been able to successfully grow particles that are nearly identical, delivering essentially defect-free superalloy metal nanoparticles.
Specialized in-house facilities
The team of Sandia researchers perform these highly specialized experiments with the unique combination of the in-house Gamma Irradiation Facility (GIF) and the Ion Beam Materials Research Laboratory (IBMRL), which provide the radiation environments demanded by this research.
“The target solutions are placed in the testing cells at the GIF where they are exposed to a variety of gamma irradiation test configurations and controlled radiation dose rates,” says Don Berry (1382), GIF supervisor. “High-intensity radioactive sources, which are kept submerged below 18 feet of deionized water to shield workers from radiation, are then raised via elevators into the testing cells to irradiate the targets. Once the irradiation is completed, the radioactive sources are returned to their shielded location in the water pool, and workers can again safely enter the cells.”
In their study of the particle growth, the researchers exposes the test solutions to even higher doses of radiation at the IBMRL.
“The ion beam irradiation experiments take place in a custom-built cell at the external beam end-station of the Tandem Van de Graff accelerator and result in intense dose rates in the solution,” says Jim Knapp (1111). “A beam of protons exits the vacuum and passes through a thin Kapton film before entering into the target solution. The system can expose targets for up to several hours, but the exposures needed in these experiments are usually only fractions of a second.”
Studying the outcome
After irradiation at the GIF or IBMRL, samples — none of which are radioactive — are studied using a variety of techniques, such as ultraviolet-visible spectroscopy and high-resolution transmission electron microscopy to understand what effects time and experimental variables have on particle formation, size, shape, and composition.
Depending on the combination of reactants, dose, and dose rate of radiation, researchers have been able to create nanometer-sized particles of gold in a variety of shapes including spheres, rods and pyramids.
Researchers are also translating the results of these experiments into computer simulations. Kevin Leung (1133) is leading the effort to use ab initio molecular dynamics, along with other methods, to interpret and understand the controlling factors in the researchers’ experiments.
“Using the results from the experiments, together with Sandia’s world-class computational capabilities, we’ll simulate the structure of the nanocrystal initiation,” Kevin says. “By examining the free energy present in the interface between the different materials, we will be able to understand what factors govern the size of these metal alloy nanocrystals.
“Modeling this region of the metastable phase space right after radiation has been applied promises to be a new and exciting area of research.”
“What we’re doing is really breaking ground in fundamental research in the science of the formation of superalloy nanoparticles,” Tina says. “This is really the new frontier in superalloys.”
Tina Nenoff’s superalloy research team includes Kevin Leung (1133), Don Berry (1382), Jim Knapp (1111), Paula Provencio (1111), Dana Powers (6770), Jason Jones (1133), and project manager Carlos Gutierrez (1133). -- Darrick Hurst
To enhance protection of military assets from mortar and small rocket attacks, Sandia, the Air Force Research Laboratory, and Raytheon Missile Systems Group successfully tested a prototype solid-state laser defense weapon built on the already-existing US Navy Phalanx platform.
The Phalanx close-in weapon system (CIWS - pronounced “sea-whiz”) is a fast-reaction Gatling gun deployed on Navy ships to protect against anti-ship missiles.
In the tests, the Laser Area Defense System (LADS) replaced the Gatling gun on the Phalanx with an off-the-shelf invisible-beam laser capable of destroying incoming targets. The tests were designed to determine if the weapon — based on a commercially available fiber-based laser system — could rapidly destroy mortar threats. The tests represented a major step in deploying a laser-based system to fill critical defensive military and homeland security needs, researchers say.
On the right track with fiber lasers
“Our simulation predicted that industrial fiber lasers with moderate power capabilities, simplified beam control, and limited beam quality could provide an initial near-term solution to the problem,” says Frank Brueckner, Raytheon program manager, “However conventional wisdom held that more power and a nearly perfect beam would be needed. These tests proved we are on the right track with the fiber laser.”
Sandia was contacted to perform experiments demonstrating the laser technology. Two rounds of testing were done in New Mexico. The first round occurred indoors, at the Labs’ Explosive Components Facility (Bldg. 905). The second round occurred outdoors, at the Terminal Ballistics Facility (Bldg. 6750 in Tech Area 3).
Marcia Cooper (2554), principal investigator for both phases of the project, says the tests helped researchers understand how the time required to destroy the mortar depended on the explosive material, the mortar spin rate, and the on-target laser energy.
“Ignition and burning of explosive,” Marcia says, “can vary from a somewhat benign reaction that just slightly ruptures the mortar’s case to complete fragmentation of the case and rapid burning of the bulk explosive.”
Ignition time and lethality
To determine if a laser-based system is effective, researchers care about both ignition time and target lethality, Marcia says. “The laser system must ignite the explosive within a munition quickly and must create a sufficiently violent reaction to minimize collateral harm,” she says. A defensive weapon cannot leave a nearly intact mortar round with a lot of explosive, Marcia says, because it could still successfully hit its target causing significant damage.
The Explosive Components Facility evaluated the laser firing on stationary and spinning mortars in a large test chamber. After those tests successfully demonstrated the laser’s effectiveness in destroying the mortars, the next step was to test the laser outdoors and at long ranges.
The team wanted to show that the LADS could destroy a mortar with sufficient destructiveness to negate its threat, so that it could then be deployed in a wider array of applications — potentially even in or near land-based assets near populated areas.
In the outdoor tests, Sandia technologist David Wackerbarth (2552) says that Raytheon researchers wanted to see if they could destroy an unfuzed, 60-mm round with the laser over a long distance, in such a way that the mortar would deflagrate (burn) rather than detonate. Deflagrating a mortar destroys the mortar without the concentrated energy release of detonated explosives. It could also mean fewer mortar fragments dropping down to earth.
Target mortar was 550 yards away
The tested Phalanx system replaced the normal 20-mm Gatling gun with a continuous-wave fiber laser, usually used in industrial welding applications. The laser, which required a 270-kW diesel generator, was fiber-optically linked to the Raytheon-developed beam director located on the Phalanx mount.
The target mortar was placed on a stand some 550 yards from the Phalanx mount. The beam director consisted of a series of mirrors that positioned and focused the beam downrange to the desired spot diameter onto the target mortar. After maintaining the beam positioned on the mortar, the explosive was heated sufficiently to cause complete destruction of the casing and burning of the explosive.
Sandia’s customer was pleased with the testing, according to Mike Booen, vice president of Advanced Missile Defense and Directed Energy Weapons at Raytheon Missile Systems in Tucson, Ariz.
“In just six short months,” Booen says, “Raytheon and government engineers went from an idea to operational field testing of a solid-state laser system that offers the potential of near-term protection for our troops.”
“Sandia's Explosive Components Facility and the Terminal Ballistics Facility turned out to be the ideal places for these experiments,” says David Wackerbarth.The test group hopes to continue research to better understand the pre-ignition processes in explosive materials under a variety of conditions. Understanding explosive response to previously inaccessible heating rates, says Marcia, will advance Sandia’s own thermal hazards program while aiding in the development of a roadmap for force protection deployment of a LADS-type system.-- Stephanie Holinka
Sandia assisted 293 small businesses in 2006 with projects ranging from a kids’ car organizer to a radio frequency signal that can alert 85-90 percent of drivers that a first responder is approaching.
This was Sandia’s sixth year of helping small businesses through the New Mexico Small Business Assistance Program, thanks to a tax credit passed by the New Mexico Legislature.
The program allows Sandia to apply a portion of the gross receipts taxes it pays to the state each year to provide technical advice and assistance to New Mexico small businesses. During 2006, Sandia received nearly $1.8 million in tax credits.
Due to successful legislation in 2007 the program has made some significant changes, says Jennifer Kamm Sinsabaugh (9118). Los Alamos National Laboratory now has the same program and the maximum amount of tax credit was increased from $1.8 million to $2.4 million for each participating laboratory.
There are few requirements for small-business participation — mainly that assisted companies must be for-profit New Mexico small businesses, and that the help is otherwise not available for a reasonable cost through private sources.
Car organizer for kids
Utilizing Sandia’s rapid prototyping technology, Bart Chavez (2455) built the first prototype of a new car organizer for kids.
The Kids Console, by Baby Azul, is the only car organizer that is reachable and usable by children strapped in child safety seats. The organizer can be placed on a bench seat or between bucket seats and allows children access to their cups, books, or toys. An extra storage compartment in the console can be used for items that parents want to keep out of reach of their children. The console is held securely in place with the seat belt on a bench seat and with a strap system when placed between bucket seats.
The Sandia assistance involved computer-aided design model analysis, stereolithography (STL) file generation, STL file verification, rapid prototyping (RP), and post-processing of the Kids Console RP model. The model allowed for the product to be shown at trade shows and to generate interest.
The New Mexico Manufacturing Extension Partnership assisted Baby Azul by developing a manufacturing feasibility study.
When company representatives attended their first trade show, they received positive feedback that encouraged them to press forward and have the Kids Console product manufactured. Without the prototype, Baby Azul would have not gone to the trade show and not pursued the idea any further, says Dawn Winters-Rizika, owner of Baby Azul.
“It is always an honor to work with the innovative and remarkable individuals in our community,” says Bart, who has helped with about 10 other small business projects over the years.
“I support the [New Mexico Small Business Assistance] program 100 percent. It’s great to help people with their ideas.”
Winters-Rizika says the Sandia program played an essential part in helping her bring the Kids Console to market.
“We will be receiving our first shipment at the end of June and this wouldn’t be happening if I hadn’t received my first prototype from
Sandia Labs,” she says. “Sandia has helped make my idea come to life.”
Emergency vehicle approaching
Force 4 Enterprises in Albuquerque has created an alert system that first responders — police, firefighters, ambulance companies — can use to alert motorists of their approach when navigating through traffic during an emergency.
Michael Frasier, co-owner of Force 4, says the system will alert motorists by sending a message or tone, which can be heard on the existing sound system of any motor vehicle if the operator is listening to any publicly broadcast radio station. This amounts to nearly 90 percent of vehicles on the road, according to Arbitron Radio Ratings and Media Research, he says.
“No one has managed to bring this technology forward,” Frasier says. “We’re using common technology in a way that has never been used before.”
The Eagle 1000 RF Siren can be detected a quarter of a mile from the approaching first responder and the area of complete capture is nearly one-tenth of a mile, he said.
First responders have traditionally relied on conventional audio sirens to warn motorists that they are approaching. Over the years, their effectiveness has been reduced by better soundproofing in today’s automobiles, Frasier says. Automobile accidents are the number one hazard facing first responders and accidents have been the leading cause of police officer deaths for the last eight years, says Frasier, citing the National Law Enforcement Officers Memorial Fund.
“Our mission is to improve the safety of the general public and for first responders when and where they interact,” he says.
Sandia retiree Richard Sparks assisted Force 4 with engineering and research guidance on the Eagle 1000 RF Siren. Richard called on 38 years of experience in assisting with radar and RF transmission issues.
Richard also provided Force 4 a number of contacts from the Center for Commercialization and Entrepreneurial Training and the National Institute of Justice.
“The idea that Michael Frasier is pursuing could save many lives that are lost across the country when people are unaware of emergency vehicles approaching and fail to yield,” Richard says. Force 4 is in a circuit design stage moving into a test phase within the next few months. -- Michael Padilla