Shehryar Khan redefines how metals behave under extreme conditions

When two metals collide at supersonic speeds, sometimes the materials bond to each other and, at other times, the integrity of the metals can fail.  

This can be an issue in manufacturing in industries such as aerospace, defence and energy that rely on bonding different materials together. Researchers have recognized that certain metals like aluminum and steel are simply too different to join using impact-bonding techniques like cold spray. Instead of sticking together, the particles can bounce off, break apart or even explode. 

But new research led by Dr. Shehryar Khan, PhD, an assistant professor at the University of Calgary’s Schulich School of Engineering in the Department of Mechanical and Manufacturing Engineering, is opening the door to new possibilities in advanced manufacturing, especially for components made from multiple metals, which could even stretch to other areas such as 3D printing. 

His work reveals that, under the right conditions, metals can form a strong bond in just billionths of a second, thanks to a microscopic layer of molten material that can be generated on impact, which freezes almost instantly during the collision event. 

Chasing the edge of the ‘impossible’ 

Khan’s curiosity about extreme metal behaviour was shaped early in his career. 

“My background is rooted in the traditional world of welding and joining,” says Khan. “But I have always been drawn to the ‘impossible’ limits of materials science.” 

That instinct led him to join a research group at Massachusetts Institute of Technology. Here, he began studying how tiny metal particles behave when launched at extremely high speeds. The team explored whether these particles could be used to bond metals without traditional heat‑based welding. 

At the time, many experts were skeptical, especially when it came to joining aluminum particles to steels. 

Turning failure into discovery 

Early results seemed to confirm the doubts. 

“In those first experiments, the aluminum particles would simply shatter or explode on impact, rather than stick,” says Khan. “It was disappointing to watch the samples disintegrate at the exact speeds where we expected bonding.” 

Instead of walking away, the researchers looked closer. 

When they examined the “failed” impacts under powerful microscopes, they noticed something unexpected: tiny traces of melting caused by special microscopic structures inside the aluminum alloy. 

That’s when the breakthrough idea emerged. 

“If we couldn’t force the metals to bond mechanically, could we use that molten material as a kind of nano-welding to bridge the gap?” says Khan. 

That question changed everything. 

Bonding in nanoseconds 

The team discovered that when only an extremely thin layer of metal melts, it can freeze almost instantly during impact, before the particle has time to bounce away, creating a permanent bond. 

The findings introduce an entirely new bonding mechanism for cold spray that relies on speed, precision and controlled melting, rather than impact-based metallurgical bonding. 

Why it matters beyond the lab 

This discovery has implications far beyond the microscope. 

Khan believes it could unlock new approaches to 3D printing and advanced manufacturing, especially for components made from multiple metals.

“By engineering the internal structure of metal powders, we can control how they bond during high‑speed impacts,” Khan says. “That gives us a powerful new way to manufacture high‑performance parts.” 

Khan says industries such as aerospace, defence and energy could benefit from stronger, more-efficient manufacturing and repair techniques that use less heat and energy than traditional methods. 

Building manufacturing expertise at UCalgary 

Since joining the UCalgary, Khan has been focused on translating his research into real‑world impact. 

“This work has sparked important conversations about the advanced-manufacturing capabilities we can develop here,” he says. “We’re actively building infrastructure within the Schulich School of Engineering to help address the manufacturing challenges faced by local industries.” 

He hopes the broader community recognizes that UCalgary has both the expertise and tools to help Southern Alberta industries expand their research and development capacity. 

Looking ahead 

As a newcomer to Alberta, Khan is now learning about the province’s specific materials challenges and exploring collaborations across sectors. 

“My goal is to apply my skills to the very practical needs of our local economy,” he says. 

And, if there’s one takeaway from his research experience, it’s this: “Even when intuition tells you something is impossible, it’s worth exploring creative possibilities. Sometimes, trying to make something work, even when it fails, teaches you how to solve the problem anyway.” 

In Khan’s case, that mindset led to a discovery that bonds metals in a billionth of a second and helps reshape the future of how things are made.