Aerospace, Military & Defence
Ensuring high reliability in aerospace materials and electronics with SAM
Scanning Acoustic Microscopy (SAM) has become a critical non-destructive testing method for confirming high reliability in aerospace and defence applications by detecting hidden flaws and validating material integrity. PVA TePla OKOS explains more
I
n aerospace and defence, the electronics and materials incorporated into satellites, aircraft, and defence platforms are expected to function in conditions that push the limits of materials science and engineering design. Unlike consumer-grade devices, which may tolerate minor faults, aerospace devices cannot afford a single unexpected failure, since mission success and human safety depend on consistent performance. This principle forms the foundation of a high-reliability approach – an engineering philosophy focused on designing and manufacturing systems, components, and processes that must perform dependably under mission-critical or extreme conditions. Such conditions may include severe temperature fluctuations, intense mechanical shock and vibration, and corrosive environments.
Achieving high reliability in aerospace and defence requires the deliberate selection of specialized materials coupled with durability-focused design practices to ensure structural and electrical integrity when subjected to extreme stress. To counter continuous vibration and sudden mechanical shocks, components are often housed in metal enclosures, and their materials are selected for their proven resistance to fatigue and cracking under dynamic loads. High-reliability components may also incorporate specialized coatings and corrosion-resistant alloys that protect against moisture, salt, and fuel vapours. To withstand prolonged mechanical and environmental stress, materials are layered and bonded in a way that helps prevent delamination and surface fractures. However, even with the most advanced designs and high-performance materials, tiny flaws in electronic assemblies or structural components can trigger system- wide failure once in operation. Hidden defects such as microscopic voids in solder joints, delamination within composite
38 May 2026
structures, or cracks in semiconductor packages may remain undetected during fabrication. When subjected to the extremes of vibration, thermal cycling, or radiation, such flaws can compromise the entire system.
Testing is therefore an essential element of high reliability to ensure potential weaknesses are identified, functionality is verified, and systems demonstrate lasting dependability prior to deployment. This is where non-destructive evaluation methods become indispensable.
Ultrasonic NDT
Ultrasonic non-destructive testing (NDT) has long served as a core inspection method within the aerospace and defence sectors. This technique employs high- frequency sound waves to detect even the smallest defects in components or assemblies without inflicting any damage. By transmitting these sound waves into electronic materials and structures, ultrasonic inspection can expose hidden internal flaws that would not be visible through external examination alone. Scanning Acoustic Microscopy (SAM) is a more specialized ultrasonic method that uses much higher frequencies, usually between 50 megahertz and several gigahertz.
“SAM extends defect detection to an entirely new scale: scans that were once limited to 500-micron flaws can now reach down to 50 microns, exposing imperfections that previously went undetected,” says Hari Polu, President of PVA TePla OKOS, a US-based manufacturer of SAM and industrial ultrasonic non- destructive (UT-NDT) systems. Unlike conventional ultrasonic NDT, which is used to detect flaws in large components with complex shapes, SAM is designed to generate highly detailed acoustic images of microstructures and stacked flat layers.
Components in Electronics
“SAM’s high-frequency operation delivers exceptional resolution at the micron or sub-micron level, a precision best suited for analysing thin samples and layered microstructures,” says Polu.
SAM applications in electronics and metals
In the semiconductor and electronics industries, the need for non-destructive failure analysis and reliability testing is accelerating
Beyond the semiconductor components themselves, today’s electronics products contain various specialty metals, alloys, plastics, and glass components. All semiconductor components need to be enclosed and packaged in consumer usable form factors. As a result, SAM equipment
has evolved and is now being used to detect subsurface flaws, dis-bonds, cracks, and other irregularities in these types of materials that constitute the “packaging” of semiconductor components.
Today, the same rigour of quality testing and failure analysis is also being applied to validate the integrity of diffusion bonded metals. When bonding similar materials, bond strength can approach that of the base metal itself. For dissimilar materials, bond performance depends on the type of intermetallic compounds that form, the thickness of the intermetallic layer, and the presence of microscopic defects such as voids at the interface. To ensure the quality of the interface, materials engineers must analyse samples to validate the quality of the bond.
www.cieonline.co.uk
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48
