Trusted technology allows engineers to avoid catastrophe when working in high-stakes applications

September 2018 - The flawless performance of a jet engine is made possible by a combination of specialty materials and technological prowess. Clever designs involving advanced alloys and coating technology have solved difficult challenges for materials used in the extreme conditions found in aircraft engines.

Coatings applied as surface finishes or pre-treatments before priming or painting protect against wear, corrosion and in the case of a turbo engine, high temperatures. Material science and engineering professionals don’t take risks that will compromise quality and safety. In order to ensure the titanium in a jet engine or stainless steel in automotive fuel injectors are up to the task, fabricators rely on techniques like X-ray Fluorescence (XRF) surface scanning technology to reduce the risk of catastrophic failure, premature malfunction and costly recalls. XRF also assists to control costs related to over-plating or rework, according to Hitachi High-Tech Analytical Science’s Product Manager Matt Kreiner.

Compared to other analytical techniques, the XRF analyzer is fast, (taking a few seconds to a minute long), easy to operate, regardless of whether the user is a novice or seasoned pro.

XRF can be used to measure the volumetric presence of thousands of metal alloys—including carbon and stainless steels, nickel, copper, aluminum, titanium, magnesium—as well as metallic coatings.

“Coatings that can be measured with XRF include chemical vapor deposition (CVD) and physical vapor deposition (PVD) on the order of nanometers to hot-dip galvanizing (HDG) and electroless nickel (EN) to complex plating structures comprised of multiple layers and alloyed layers,” explains Kreiner. “XRF is a field-proven technique that evolved to the point where most any metal-based plating can be measured reliably and to specification.”

High-resolution detection

Hitachi High-Tech, Westford, Massachusetts, has introduced a new configuration of its X-Strata920 coatings and materials analyzer. A new high-resolution silicon drift detector (SDD) improves the model by offering higher accuracy and precision for complex coating structures and base metals, the ability to directly measure phosphorus composition in phosphate-based coatings, shorter measurement times and better detection limits to measure thinner coatings on the order of nanometers.

Phosphate conversion coatings are applied to steel components for corrosion resistance, lubricity or as a base for additional coatings or paint. They are commonly used in components exposed to the environment or built for applications in automotive, transportation, aerospace, industrial equipment and fasteners, says Kreiner. The SDD also makes it possible to measure nanometer-scale coatings, which are found in the electronics industry (e.g. circuit boards) and on medical devices and tools.

Hitachi High-Tech recently introduced a new configuration of its X-Strata920 coatings and materials analyzer, a new high-resolution silicon drift detector (SDD) improves the model by offering higher accuracy and precision for complex coating structures and base metals, among other benefits.

Compared to other analytical techniques, Kreiner says the fast (typically a few seconds to one minute long) XRF analyzer is easy to operate, regardless of whether the user is a novice or seasoned pro. For 40 years, Hitachi High-Tech has designed nondestructive XRF coating analysis tools to solve the challenges faced by coaters and platers. “All Hitachi High-Tech XRF products are focused on doing two things: delivering high precision results and simplifying the operation so that anyone in the facility can use the tools and get the right results the first time,” Kreiner says.

Flexible power

XRF can be used in a lab or production setting to scan and profile small samples or test coupons, or be configured for automated in-line analysis, or operated as a portable handheld. Many XRF instruments can be configured to perform additional tests such as elemental composition and metal alloy identification. These tests enable inspection and production staff to ensure the material base and finishes are correct for the intended application, thereby avoiding failure in service and costly liabilities.

Hitachi High-Tech offers additional technologies for metals analysis using Optical Emission Spectroscopy (OES) and Laser-Induced Breakdown Spectroscopy (LIBS).

Handheld XRF technology scans large automotive and aerospace parts that must be directly tested (which is more thorough than just using a test coupon) and don’t fit into a benchtop instrument. The mobile device is also helpful to measure busbar in power distribution, where large copper or aluminum strips are plated with different materials whose thickness must be precisely controlled in order to deliver proper conductivity over the intended life of the electrical apparatus.

XRF can be used to scan and profile small samples or test coupons, be configured for automated in-line analysis, or operated as a portable handheld.

“In recent years, XRF instruments have become smaller, smarter and easier to operate,” says Kreiner. Benchtop instruments are still the norm in most testing laboratories but the newer “point-and-shoot style XRF handheld instruments are continuing to improve and close the gap with their larger relatives.”

With some of these technologies, he continues, “There is almost no difference in analytical performance between bench tops and handhelds. The user needs merely to decide which format makes the most sense.” He notes that Hitachi High-Tech’s coating team can help customers determine which instrument is best suited based on application requirements.

Before critical components are sent out to be assembled into aircraft or automobiles, the latest version of X-Strata920 scans metal surfaces to ensure components or assemblies are plated or coated adequately and evenly according to specifications—whether to provide protection from corrosion, wear and heat, or for decorative purposes.

Some of the additional end uses XRF inspection technology applies are medical equipment, military, communications, power, electronics, industrial equipment (e.g., heat exchanger coils, down-hole drilling equipment), tooling, appliances, jewelry and consumer goods.

“As the demand for 100 percent inspection continues to grow, manufacturing and production will increasingly depend on XRF for rapid, nondestructive confirmation testing,” Kreiner says. MM