The rapidly evolving aerospace industry is constantly exploring ways to improve efficiency, performance, and safety while reducing carbon emissions and maintaining sustainability.
In recent years, several technological advancements have expanded the capabilities of air travel both within the Earth’s atmosphere as well as outside it. This includes advanced satellite technology for communications, additive manufacturing for lightweight components, electric propulsion for reduced emissions and reduced costs, supersonic flight for faster travel, and artificial intelligence and machine learning for enhanced operational efficiency.
Aerospace focuses on advanced materials with very specific properties. Systems usually involve different kinds of materials, ranging from ceramic thermal to carbon fiber and Titanium, which are used for myriad purposes to optimize performance.
The research in this area aims to develop multifunctional materials, which means materials that have not only structural functions but can also offer other features like active cooling. To bring advanced aerospace concepts to life, materials must be more durable, lightweight, and cost-effective than ever before.
As the aerospace industry continues to progress, let’s examine the latest groundbreaking innovations that will take it even further.
Unlocking ‘Materials Genome’ to Advance Design
Last month, researchers from the University of Sydney’s School of Aerospace, Mechanical, and Mechatronic Engineering discovered a microscopy method for unraveling atomic relationships within crystalline materials such as advanced steels and custom silicon.
This means that researchers can detect even minute changes in the atomic-level architecture of these materials, enhancing our understanding of the fundamental origins of their properties and behavior. This knowledge will enable the development of advanced semiconductors for electronics and lighter, stronger alloys for the aerospace sector.
For this, researchers used atom probe tomography (APT), a technique that visualizes atoms in three dimensions (3D), to unpack the complexity of short-range order (SRO). SRO is a quantitative measure of the relative tendency for a material’s constituent elements to deviate from a random distribution. Understanding the local atomic environments is essential for creating innovative materials.
By quantifying the non-randomness of neighborhood relationships at the atomic scale within the crystal in detail, SRO opens up “vast possibilities for materials that are custom-designed, atom-by-atom, with specific neighborhood arrangements to achieve desired properties like strength,” said the study lead, Professor Simon Ringer, who is the Pro-Vice-Chancellor (Research Infrastructure) at the University of Sydney.
Sometimes referred to as the ‘materials genome,’ SRO has been a challenge to measure and quantify. This is because atomic arrangements occur at such a small scale that you can’t see them with conventional microscopy techniques.
So, the team of researchers developed a new method using APT that overcomes these challenges, making it “a significant breakthrough in materials science,” said Ringer, a materials engineer at AMME.
The study’s focus has been on high-entropy alloys (HEAs), a heavily researched area due to their potential for use in situations that require high-temperature strength, including jet engines and power plants.
Using advanced data science techniques and drawing on data from APT, the researchers observed and measured SRO. They were then able to compare how SRO changes in a high-entropy alloy of cobalt, chrome, and nickel under different heat treatments.
According to Dr Andrew Breen, a senior postdoctoral fellow:
“(The study has produced a) sensitivity analysis that bounds the precise range of circumstances whereby such measurements are valid and where they are not valid.”
By measuring and understanding SRO, this study could also help transform approaches to materials design and show just how “small changes at the atomic level architecture can lead to giant leaps in materials performance,” said Dr. Mengwei He, a postdoc research fellow in the School of Aerospace, Mechanical, and Mechatronic Engineering.
Moreover, by providing a blueprint at the microscopic level, the study enhances a researcher’s capabilities to computationally simulate, model, and then predict materials behavior. It can further act as a template for future studies in which SRO controls critical material properties.
A New Material to Make Hypersonic Flight Possible
There is a lot of interest in achieving sustained flight at hypersonic speeds, but technical challenges remain. These include managing extreme heat, developing materials that can withstand stress, extreme temperatures, and oxidation without compromising performance, and creating propulsion systems that can operate efficiently at high speeds and altitudes.
As researchers try to find solutions to these problems, scientists from Guangzhou University School of Materials Science and Engineering reported a breakthrough in hypersonic heat shields earlier this year.
In what could be a game changer for hypersonic flight, the scientists developed a new material, porous ceramic, that provides “exceptional thermal stability” and “ultrahigh compressive strength.”
This has been achieved using a multi-scale structure design, which the scientists say has been done for the very first time. Moreover, the quick fabrication of this high-entropy ceramics opens the door to wider exploration in the sectors of aerospace, chemical engineering, and energy production and transfer.
The researchers said the ceramics were fabricated through “an ultrafast high-temperature synthesis technique that can lead to exceptional mechanical load-bearing capability and high thermal insulation performance.”
To address the challenge of strong, lightweight materials with low thermal conductivity, scientists used ceramic materials that are non-combustible and corrosion-resistant, have high melting points, and exhibit low thermal conductivity. Of course, conventional ceramic materials are still insufficient at handling extremely high temperatures and pressure.
While lightweight, porous materials have low thermal transfer capabilities, they also come at the expense of greater fragility.
So, the researchers began to work on simultaneously improving “the mechanical strength and thermal insulation capacity of porous ceramics.” This led them to the high-entropy concept, which focuses on multiple elements in equal measures to create stronger, more stable, and more heat-resistant components.
The scientists found the newly created ceramic material — called 9-cation porous high-entropy diboride (9PHEB) — successful in striking a good balance between heat resistance and strength without the usual limitations. This new material also accomplished the required weight and insulation standards for aerospace flight.
According to researchers:
“High-quality interfaces, characterized by strong bonding without defects or amorphous phases, can promote the rapid force transfer along the building block and to many other ones through connections upon loading, leading to a significant enhancement of mechanical strength.”
The study also noted that the new material 9PHEB is exceptional in terms of both strength and thermal stability.
Self-Healing Materials for Aerospace Structures
Self-healing polymers and nanocomposites are innovative materials that have significantly advanced the aerospace industry. They have also been the subject of significant research for their applications in electronics, batteries, biomedical, and other technical fields.
Although self-healing materials have existed for many centuries, there has been a significant uptick in innovation in this field over the past few decades, leading to the development of synthetic self-healing materials.
These materials can be found in different forms, depending on their unique chemistry, including thermoplastic polymers, thermoset polymers, elastomers, shape memory polymers, polymer composites, and nanocomposites.
Depending on their capability, these materials are often referred to as intrinsic self-healing materials, which rely on chemical bonds or molecular mobility within the material itself, or extrinsic self-healing materials, where external healing agents activate upon damage.
Polymers are considered particularly important in structure usage due to their amazing ability to repair structural damage. This is achieved through polymer chain mobilization and cross-linking.
In the aerospace industry, self-healing nanocomposites are particularly useful for engineered structures, adhesives, engines, fuselages, and coatings. Self-healing nanocomposites are fabricated by incorporating nanoparticles in polymers. For their ability to heal damage reversibly, thermosets and thermoplastic polymers are reinforced with nano-carbon nanoparticles.
Nanofillers further boost the self-healing effect of nanocomposites. The type and content of nanofiller are essential factors in initiating the self-healing effect.
Traditionally, ceramic and metallic materials were used to develop the engines. However, more recently, polymeric materials and composites have increasingly been utilized in high-temperature-resistant jet engines. This shift is for a good reason, as composite materials better resist structural damage from impact or failure.
With ceramic fibers capable of withstanding very high temperatures, self-healing nanocomposites have been used to produce fixed and mobile jet engine components. These nanomaterials have also been found to be resistant to pressure, damage, and corrosion, contributing to improved engine efficiency.
The ongoing research in self-healing polymers shows potential for materials that can withstand high pressure, temperature, and impact situations to improve the durability of space structures substantially. We may even see the development of nanocarbon nanocomposites in the future that sense damage in aerospace structures, but that would require new healing agents with superior self-healing efficiency.
Interestingly, in the world of self-healing materials, Dr Kunal Masania, an associate professor of aerospace structures and materials at the Delft University of Technology in the Netherlands, developed “living materials” for use in the aerospace sector. These living materials contain microorganisms like bacteria and fungi, giving them the capability to self-heal.
The team chose fungi for their ability to tolerate harsh conditions and their relative ease of cultivation. Fungal cells can also connect, which means that by distributing only a few cells throughout the material, they can reconnect and form a sensing network. These living materials are actually produced through a special 3D printing method and a new 3D printing ink.
This development was made as part of a five-year project, AM-IMATE, which was awarded a grant from the European Union. According to Masania:
“(The goal of the project is) to make engineered structures that can behave like living organisms, able to sense and adapt to mechanical stresses.”
By using biological self-healing materials, not only can the durability and performance of critical structures used in aerospace be improved, but it can also be sustainable. The AM-IMATE team is actually exploring the use of composites as the core material for airplane interiors.
“Our materials are very lightweight and more sustainable than currently used materials,” said Masania, adding that replacing the plastic and metal means we won’t have to rely on fossil fuels. Also, “the aircraft components could be dismantled and returned to nature,” he said.
But this is not all. The team even sees their living materials forming the basis of new habitats “on other planets” by using local materials and binding them together with fungi.
Companies Leading in Aerospace Technology
If we look at the companies operating in the aerospace industry, several key players are advancing technology, including General Dynamics Corporation (GD), SpaceX, Virgin Galactic, and Sierra Nevada Corporation.
Lockheed Martin Corporation (LMT), one of the largest defense contractors in the world, is also a popular one in this sphere. Known for its fighter jets, missile systems, and space exploration technologies, Lockheed Martin has developed an AI-based telecommunication software called Callisto in collaboration with Amazon and Cisco to improve efficiency and situational awareness onboard spacecraft. Most recently, it acquired satellite-based solutions provider Terran Orbital in a $450 million deal.
Boeing is another major player in commercial and military aerospace. The company is currently under intense scrutiny for quality control issues, ongoing problems with its 737 Max aircraft, handling safety concerns, and competition from Airbus.
Airbus is primarily involved in the design and manufacturing of commercial aircraft. To reduce its products’ CO2 emissions, the company is developing bio-derived materials for aircraft production. For this, the company is looking into alternatives to carbon fibers derived from fossil fuels that are used in building components like wings or fuselage shells.
Now, let’s take a deeper look into a couple of prominent names:
#1. Raytheon Technologies
Focused on avionics, defense electronics, and missile systems, in 2020, Raytheon completed its merger with United Technologies to form the world’s most advanced aerospace and defense systems provider.
As the company continues to deliver its products and expertise globally, some notable developments this year include:
- Being chosen by DARPA for quantum optical sensors used in imaging applications.
- Unveiling MAYA as the future of premium air travel.
- Investing $200mln in Spokane to fuel manufacturing growth.
- Completing the Crew Capability Assessment test of its next-gen spacesuit for the International Space Station.
- Being awarded a $344mln contract to modernize electronics unit for missile development program.
As of writing, Raytheon (RTX:NYSE) shares are trading at $118.35, up 40.66% YTD. The company’s market cap is $157.43bln, and its dividend yield is 2.13%.
For Q2 2024, the company reported $19.7bln in sales, an increase of 8% from the previous year, while its operating cash flow was $2.7bln. Raytheon noted a backlog of $206bln, including $129bln of commercial and $77bln of defense. Adjusted EPS was $1.41, up 9% versus the prior year.
“RTX delivered strong operational performance in the second quarter, with 10 percent organic sales growth, adjusted margin expansion across all three segments, and $2.2 billion in free cash flow.”
– RTX President and CEO Chris Calio
He also noted that with the backlog and “unprecedented demand across our portfolio,” they are focused on investing in innovative technologies and capabilities.
#2. Northrop Grumman
Specializing in defense and aerospace, Northrop Grumman is renowned for its work in unmanned systems, cybersecurity, and advanced space systems, including the James Webb Space Telescope. The company is also developing the B-12 bomber and the Sentinel program. Additionally, Northrop Grumman is collaborating with Elon Musk’s SpaceX on a U.S. spy satellite system, partnering with EpiSci on advanced autonomy capabilities, and supporting Norway’s long-term defense plan through its work with Andøya Space.
As of writing, Northman shares are trading at $504.87, up 7.85% YTD, which has the company’s market cap at $73.83bln. It pays a dividend yield of 1.63%. For Q2 2024, the company reported an increase of 6.7% in revenue to $10.22bln. The quarter saw over $1.11bln in free cash flow, while expenses included about $3 billion in R&D and $1.8 billion in capital expenditures. Northrop’s EPS beat estimates by 7.6% by coming at $6.36.
The company has projected solid growth across its divisions, particularly in aeronautics, weapon systems, and advanced electronics. A slight decline is expected in its space segment next year due to a canceled program, but growth is anticipated to resume after that. While acknowledging supply chain constraints, specifically in sourcing ammonium perchlorate for solid rocket motors, CEO Kathy Warden mentioned that they are working with the Air Force to reduce costs.
Click here for a list of top 10 aerospace and defense stocks.
Conclusion
The aerospace market currently stands at around $300 billion. While it briefly declined during the COVID-19 pandemic, it is expected to exceed $460 billion by 2028. Meanwhile, the revenue of the aerospace parts manufacturing market is projected to surpass $1,230 billion at the end of this decade.
Given the growth the industry is seeing, technological innovation is happening at a rapid pace. From more efficient aircraft through electric propulsion systems, the creation of advanced composite materials, and progress in AI and sensor technology to achieve fully autonomous aircraft to research and adoption of sustainable aviation fuels (SAFs), which are derived from renewable sources, a lot is happening and together these innovations can bring a lot of serious changes to shape the future of aerospace.
Click here for a list of the five best aerospace ETFs to invest in.