Some doctors still make house calls if their patients can’t come to them. What do you do when a material can’t be delivered to the lab for analysis?
Just as we take our children and go ourselves for regular wellness checks, materials are analyzed periodically from the raw material stage up through the creation of the final product, and then during the product’s lifetime. The necessity of materials analysis is summarized by American Laboratory:
The materials industry encompasses a range of product segments including polymers, composites, optical components, coatings, semiconductors, and metals. In spite of the diversity and breadth of applications, all have some common requirements that must be met. The raw materials from which engineered materials are synthesized must be analyzed for quality; the relationship between composition, structure, and performance of the material must be defined; production variables that affect performance must be characterized; the quality of the finished material must be confirmed; the effect of use on the material must be measured; and recycling and reclamation efforts must be supported.
Material analysis has to be performed on-site for variety of reasons, including: on-the-spot analysis of the raw materials; materials pre-screening; nondestructive testing of large objects; rapid data collection over large surfaces; evaluating aging and weathering of a material; and real-time measurements to enable rapid decision-making.
So how is on-site analysis performed? A variety of portable and even hand-held instruments may be light-proof, dust-proof, and water-resistant, making it possible to take spectroscopy methods to the field. Technologies include:
- Fourier transform infrared spectroscopy (FTIR) uses a broad spectrum of infrared radiation to obtain a characteristic spectrum, using the mathematical Fourier transform process (named after the 19th century French mathematician, J. Fourier). A useful tool for materials analysis in a laboratory, FTIR has been miniaturized for mobile applications. Several hand-held FTIR spectrometers are available, including the 4100 ExoScan and 4200 FlexScan from Agilent Technologies, and the TruDefender™ FTX from Thermo Scientific. On-site FTIR analysis include surface testing of composites, carbon-black-filled polymers, paints and coatings, and surface contamination.
- Raman spectroscopy, named after C.V. Raman, a 20th century Indian physicist, uses inelastic scattering of laser light to provide information about the vibrational modes in the material. It can provide information complementary to infrared spectroscopy. A portable Raman spectrometer can be useful in forensic analysis of unknown chemicals because the obtained spectra can be compared with a comprehensive library of thousands of chemicals. Several hand-held Raman spectrometers are available, including NanoRam or TacticID from BWTek, and TruScan from Thermo Scientific.
- UV-visible spectroscopy uses illumination with ultraviolet or visible light to measure material absorbance or fluorescence as a unique spectrum. Useful for transparent and fluorescent materials, the spectrometers can also measure the spectra of a light source. A palm-sized USB2000-UV-VIS Spectrometer from Ocean Optics, and a Portable Spectrometer UV-VIS (Allied Scientific Pro) can be adapted to a variety of field applications.
- X-ray fluorescence spectroscopy (XRF) is a technique that uses the emission of secondary, or fluorescence X-rays from the material bombarded by high-intensity X-rays. The technique is used for elemental and chemical analysis of metals, ceramics, glass, polymer, and construction materials. The S1 Titan Handheld XRF Spectrometer from Bruker or the SPECTRO xSORT from Spectro can be used on site to rapidly determine the presence of dozens of chemical elements in a matter of seconds.
Overall, whether used for a forensics application, a construction aging investigation, or automotive or aerospace testing, hand-held analysis tools are out there, loaded with user-friendly features, adaptive software, and remote-control possibilities.
Source: “Handheld and Portable FTIR Spectrometers for the Analysis of Materials: Taking the Lab to the Sample,” by Alan J. Rein and John Seelenbinder, americanlaboratory.com, June 7, 2013.
Source: “Field-ready Handheld Spectral Analysis Instrument,” rdmag.com.
Source: TruScan, ahurascientific.com.
Source: SPECTRO xSORT, spectro.com.
Source: USB2000-UV-VIS Spectrometer, oceanoptics.com.
Source: Portable Spectrometer UV-VIS with LCD screen, alliedscientificpro.com.
Source: “FTIR Compact & Portable Analyzers : 4100 ExoScan Series FTIR,” chem.agilent.com.
Source: “TruDefender™ FTX Handheld FTIR for Chemical Identification,” thermoscientific.com.
Source: S1 Titan Handheld XRF Spectrometer, bruker.com.