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Introducing LIBS handheld instrumentation
The process of alloy grade verification has advanced significantly with the development of portable and handheld devices that bring analytical capabilities traditionally found in the laboratory to anywhere rapid metals identification is needed. For years, handheld analysis technology has provided alloy grade identification for the testing of incoming materials and the verification of outgoing products, thus greatly improving quality by eliminating material mix-ups. Manufacturers value immediate alloy verification to avoid costly material mistakes by relying on questionable or outdated vendor certificates, and no longer have to wait for laboratory results.
To meet the rigorous demands of modern manufacturing, handheld analysis tools using X-ray fluorescence (XRF) have been the most commonly used. However, there are challenges with many of the handheld XRF analyzers that are currently available. For example, light alloying element separations can be problematic, or possible only after extended measurement times. The hardware and electronics of a handheld XRF device are also not robust enough to withstand harsh environments. In addition, the use of XRF can be regulated and requires annual registration and licensing fees, which in turn needs designated staff time to manage and will contribute to higher operating costs.
The introduction of laser induced breakdown spectroscopy, commonly known as LIBS, offers a new and improved way to identify elemental composition for both heavy and light elements. Traditionally a lab-based instrument, LIBS is now available in a miniaturized platform due to recent technological advancements. Handheld LIBS analyzers, such as the Rigaku KT-100 Katana, have the ability to measure light alloying elements and identify the most popular aluminum grades in only 1-2 seconds. This capability allows manufacturers and others to further streamline metals analysis processes for greater quality control and quality assurance.
LIBS technology uses an energetic laser pulse to excite a small area of the metal. This generates a high temperature plasma plume by ablating the surface. As this plasma cools, it emits light frequencies that are collected by the instrument detector and transmitted to the spectrometer. Each element on the periodic table has a number of unique spectral peaks. These peaks are used to calculate the concentration of elements to determine the metal alloy composition and grade classification (see figure 1). The results also include the percentages of the individual elements found. Figure 1 shows a schematic of the analytical process of KT-100 Katana.
This development rapidly expanded the use of LIBS, especially into field operations requiring on-the-spot alloy separation and analysis. LIBS is better suited for analysis of light elements such as aluminum (Al), magnesium (Mg), and beryllium (Be) than handheld XRF, and as a result quickly gained industry acceptance as a method of choice for aluminum grade identification.
As the need for aluminum used in manufacturing continues to increase globally, the role of accurate and precise identification has become more significant. Accurate alloy grade verification is essential throughout the life-cycle of aluminum-based products. This is particularly true in secondary production because scrap aluminum is often obtained from a variety of sources. Ultimately, profitability and product quality are greatly impacted by incorrect grade identification and can result in catastrophic loss in mission critical industries.
To demonstrate precision, assayed concentrations were plotted versus their certified concentrations using standards with a wide dynamic range of magnesium (Mg) and silicon (Si). Multiple measurements were taken using KT-100 Katana. Figures 2 and 3 show the device’s precision, the accurate identification of the standards’ concentration (larger blue dots) which consistently match the plotted data.
Figures 2 and 3:
Figure 4 shows the precision and reproducibility of the aforementioned handheld LIBS analyzer across multiple units. The measurements were repeated ten times per unit and resulted in consistently accurate identification of Mg concentrations.
KT-100 Katana handheld LIBS offers a new and improved way to identify elemental composition of both heavy and light elements. In comparison to handheld XRF, KT-100 is the ideal technology for identifying the most popular aluminum (Al) grades—100, 6061, and 6063 – as well as aluminum (Al) and silicon (Si) brasses and bronzes or beryllium (Be) coppers. This is in addition to other popular grades of stainless steel, nickel and titanium alloys.
By identifying the weaknesses of existing handheld metal analyzers, as well as the unmet needs of the end user, the design and features of KT-100 Katana have set this device at the forefront of handheld LIBS instrumentation. The sophisticated ergonomics consist of a pistol-shape for optimal one-handed operation via use of raised control buttons that are easily felt through work gloves or via ‘quick launch’ navigation buttons located near the trigger. The integration of proprietary breakthrough laser ablation and detection engine (BLADE) technology, means KT-100 is considerably smaller and lighter than many other handhelds, weighing only 1.5kg (3.25lbs). The unique “kick stand” foot can be used for optimum viewing and grabbing position.
KT-100 Katana has successfully passed rigorous durability tests proving its capabilities for meeting the needs of those who require a rugged handheld metals analyzer used in the harshest environments. To ensure durability in a variety of work environments, KT-100 Katana underwent strict testing to the United States Military Standard MIL-STD-810G. KT-100 passed rigorous vibration, shock, and drop testing that focused on impact to every angle of the instrument to prove the device’s durability and performance when exposed to environmental stress. In addition, its IP-54 rating and safety window of fused silica provide protection against dust, moisture, and humid environments. As the only handheld metal analyzer to have passed these tests, the KT-100 handheld LIBS is truly optimized for rugged use.
KT-100 streamlines metals verification workflow processes. It’s easy to use by operators with varying skill levels. With the longest battery life of any other handheld metals analyzer of over six hours, KT-100 is less susceptible to fatigue and downtime, which is critical for on- and off-site operations. Its macro-camera allows for sample imaging to associate results to. Additionally, the unique GPS and Wi-Fi capability allows for instrument tracking to protect the owner’s investment.
Technological advancements have increased implementation of methods and devices that promote lean processes while ensuring and improving quality. Rigaku’s KT-100 Katana handheld LIBS is the right tool to further advance quality assurance and control of metals throughout the manufacturing process.