Materials science is behind many of the advances that come to our daily lives. Research into the relationship between a material’s structure and its properties is especially relevant in sectors like defense, aeronautics, and aerospace, which are always searching for new solutions. In addition to recent advances like the arrival of the first electric passenger planes and engines like the one from the Spanish Pangea Aerospace, which are intended to revolutionize space exploration, efforts are focused on achieving **materials that challenge current limits and offer unexplored opportunities.**
Several researchers from the Massachusetts Institute of Technology (MIT) have been working on this for years, alongside engineers from the American company ATI Specialty Materials, which has extensive experience in the production of all types of metals for aircraft and military platforms. Together, this team has discovered **a method for obtaining new titanium alloys** “with an exceptional combination of strength and ductility,” which can be key to improving the performance of large turbines, aircraft components, and even space rockets.
In a study published in the journal Advanced Materials, the researchers describe how they have developed new techniques, such as cross-lamination, and modified the proportions of the elements to form **titanium alloys that are stronger, more flexible, and more durable than those available to date.**
Titanium alloys
Titanium alloys are obtained by mixing titanium with other chemical elements, such as aluminum or oxygen, and **have been used since the beginning of the 20th century with different functions and objectives.** Their primary appeal lies in their resistance to traction and corrosion, their extreme lightness, and their ability to withstand extreme temperatures. This makes them ideal for use in aerospace infrastructures such as the ISS, for example, but also for manufacturing car components, medical prostheses, and even small tools to always carry with you or rings to monitor your health.
When designing and developing alloys, there are two key characteristics that are not always easy to balance: strength and ductility. The strongest titanium is usually less deformable, and the most ductile tends to be mechanically weaker. The MIT team has worked precisely to achieve the best possible combinations, adapting the chemical composition and reticular structure of each alloy and **using unique processing techniques that will allow the materials to be produced on an industrial scale.**
Titanium alloy bars
Their mission, to find the most precise formula between alloy elements and their proportions and changing the way the material is processed, was to “create a great playing field for **obtaining good combinations of properties, both for cryogenic and elevated temperatures**,” says Cemal Cem Tasan, co-author of the paper and professor of Materials Science and Engineering at MIT in a press release.
To achieve this, it is necessary to study the atomic scale, where the two phases of titanium alloys, known as alpha and beta, are observed. “The key strategy in this design approach is **taking into account different scales**,” Tasan notes. “One scale is the single crystal structure. For example, by carefully choosing the alloying elements, you can have an alpha-phase crystal structure that allows for particular deformation mechanisms. The other scale is the polycrystal, which involves interactions of both alpha and beta phases. So the approach followed here involves design considerations for both.”
The best combination
In their laboratory research, which also included the participation of ATI engineers, these metallurgists analyzed a multitude of alloys in detail using a scanning electron microscope. They discovered, by deforming the materials to find out how their microstructures responded to external mechanical load, that **the cross-laminating technique was essential to achieve the best combinations** of strength and ductility.
In collaboration with Harvard University’s Center for Nanoscale Systems, the researchers found the combination of parameters that gave the best result, in which the alpha and beta phases shared the deformation evenly. This meant **drastically reducing the tendency for cracks to appear**, common when the phases respond differently to mechanical stress.
One of ATI Specialty Materials’ titanium alloy engines
“We studied the structure of the material to understand these two phases and their morphologies, and examined their chemistries by performing local analyses at the atomic scale. We adopted a wide variety of techniques to quantify various properties of the material across multiple length scales,” Tasan said. After comparing the results, they concluded that **the properties obtained were “much better than those of comparable alloys.”**
This research, which has led to the scientific validation of the design strategy and its mass production, will now continue its path with the support of the industry to reach the commercialization of the most promising alloys. Its potential is to mark **a before and following in the manufacturing of engine components for all types of vehicles**, aircraft exhaust systems, and satellite structures that are lighter and more resistant to extreme temperatures. Casan himself speaks of the new opportunities that it offers for “any aerospace application where an improved combination of strength and ductility is useful.”
Titanium Alloys: A New Era of Strength and Ductility
Materials science is behind many of the advances that come to our daily lives. Research into the relationship between its structure and its properties is especially relevant in sectors such as defense, aeronautics or aerospace, always in search of new solutions. In addition to recent advances such as the arrival of the first electric passenger planes y engines like the one from the Spanish Pangea Aerospace intended to revolutionize space exploration, efforts are focused on achieving **materials that challenge current limits and offer opportunities still unexplored**.
Several researchers from the Massachusetts Institute of Technology (MIT) have been working on this for years, together with engineers from the American company ATI Specialty Materials, with extensive experience in the production of all types of metals in aircraft and military platforms. Together, this team has discovered **A method for obtaining new titanium alloys** “with an exceptional combination of strength and ductility,” which can be key to improving the performance of large turbines aircraft components and even space rockets.
In a study published in the journal Advanced Materials the researchers describe how they have developed new techniques, such as cross-lamination, and have modified the proportions of the elements to form **Titanium alloys that are stronger, more flexible and more durable than those available to date**.
Titanium Alloys
Titanium alloys are obtained by mixing this metal with other chemical elements, such as aluminum or oxygen, and **They have been used since the beginning of the 20th century with different functions and objectives.**. Their main attraction lies in their resistance to traction and corrosion and their extreme lightness, but also in their ability to withstand extreme temperatures. This makes them ideal for use in aerospace infrastructures such as the ISS for example, but also for manufacturing car components, medical prostheses and even small tools to always carry with you o rings to monitor your health.
When designing and developing alloys, there are two key characteristics that are not always easy to balance: strength and ductility. The strongest titanium is usually less deformable, and the most ductile tends to be mechanically weaker. The MIT team has worked precisely to achieve the best possible combinations, adapting the chemical composition and reticular structure of each alloy and **Using unique processing techniques that will allow the materials to be produced on an industrial scale**.
Titanium alloy bars
Their mission, to find the most precise formula between the alloy elements and their proportions and changing the way the material is processed, was to “create a great playing field for **obtain good combinations of properties, both for cryogenic and elevated temperatures**” says Cemal Cem Tasan, co-author of the paper and professor of Materials Science and Engineering at MIT in a press release.
To achieve this, it is necessary to study the atomic scale, where the two phases of titanium alloys, known as alpha and beta, are observed. “The key strategy in this design approach is **take into account different scales**” Tasan notes. “One scale is the single crystal structure. For example, by carefully choosing the alloying elements, you can have an alpha-phase crystal structure that allows for particular deformation mechanisms. The other scale is the polycrystal, which involves interactions of both alpha and beta phases. So the approach followed here involves design considerations for both.”
The Best Combination
In their laboratory research, which also included the participation of ATI engineers, these metallurgists analyzed a multitude of alloys in detail using a scanning electron microscope. They discovered, by deforming the materials to find out how their microstructures responded to external mechanical load, that **The cross-laminating technique was essential to achieve the best combinations** of strength and ductility.
In collaboration with Harvard University’s Center for Nanoscale Systems, the researchers found the combination of parameters that gave the best result, in which the alpha and beta phases shared the deformation evenly. This meant **drastically reduce the tendency for cracks to appear** common when the phases respond differently to mechanical stress.
One of ATI Specialty Materials’ titanium alloy engines
“We studied the structure of the material to understand these two phases and their morphologies, and examined their chemistries by performing local analyses at the atomic scale. We adopted a wide variety of techniques to quantify various properties of the material across multiple length scales,” Tasan said. After comparing the results, they concluded that **The properties obtained were “much better than those of comparable alloys”**.
This research, which has led to the scientific validation of the design strategy and its mass production, will now continue its path with the support of the industry to reach the commercialization of the most promising alloys. Its potential is to mark the **A before and following in the manufacturing of engine components for all types of vehicles** aircraft exhaust systems and satellite structures that are lighter and more resistant to extreme temperatures. Casan himself speaks of the new opportunities that it offers for “any aerospace application where an improved combination of strength and ductility is useful.”
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