Metallurgical Associates

Check it out! MAI recognized as one of the Top Corrosion Control Service Providers by Managing Manufacturing! If you have corrosion issues, please contact MAI 262-798-8098 or [email protected] #mai #corrosion #failureanalyis #metals #metallurgy #sem #metallography

Incredible combinations…

Thank you Metallurgical Engineering for this post! If you are looking for an organization to PQR testing, contact MAI! We conduct PQR testing on all kinds of welds in a variety of metal products. Contact MAI today 262-798-8098 or [email protected]

Don't just send out your samples for SEM/EDS analysis! Schedule an in-person or remote SEM/EDS session and work with MAI's Kelly Brown. We have a few spots still available next week - contact MAI to book your time now before the calendar fills up! 262-798-8098 or [email protected]

Fourier transform infrared spectroscopy (FTIR) is a fundamental tool for the qualitative compositional analysis of polymeric materials. It allows the user to identify the material being tested. In order to properly interpret the results of FTIR, it is important to understand not only why function groups produce spectral bands at specific frequencies (wavenumbers), but also why different function groups produce bands of different strengths. FTIR spectroscopy measures the interaction between infrared energy and a series of bonded atoms within the structure of the polymer, called a functional group. The infrared energy produces vibrations within the functional groups that correspond to the bands on the FTIR spectrum there are three important pieces of information in an FTIR spectrum: spectral band positions, band heights, and band widths. When plotted in absorbance, the band heights (intensities) in an FTIR spectrum are relational to concentration, allowing infrared spectra to be used to determine the concentration of chemical species in samples. This relationship between absorbance and concentration is summarized in Beer’s law: Absorbance = Absorptivity x Path length x concentration.?Absorptivity is a constant for a given functional group in a pure molecule at a given wavenumber.?Because different functional groups in different molecules have different absorptivities, this value is necessarily be related to the chemical structure. Specifically, absorptivity is related to the electronegatively difference or partial charges on the atoms within a functional group, known as a dipole moment.?The variation in absorptivity between function groups and between the same functional group in two different molecules, accounts for why FTIR spectra contain absorption bands of different intensities.?For example, C-H bands have relatively low absorptivity so these bands tend to proportionally weak, while C=O have relatively high absorptivity and tend to be more intense. Also important in the presentation of the FTIR spectrum is the wavenumber scale. There is an alternative for the standard linear wavenumber scale. This alternate scale is made up of three separate linear ranges: ·?4000 cm-1 to 2200 cm-1 ·?2200 cm-1 to 1000 cm-1 ·?1000 cm-1 to 400 cm-1 The alternate scale allows an expanded view of the FTIR “fingerprint” region, which facilitates superior peak differentiation and identification. I have illustrated the spectral band intensities and two different scales in the spectra representing polyetheretherketone (PEEK), in the color-coded graphic below. It is my understanding that this alternate scale was first developed during the advent of the creation of infrared spectroscopy spectral libraries, both as books and later as electronic software. This was a cooperative effort between Aldrich Chemical (Sigma-Aldrich) and Nicolet (Thermo Fisher Scientific). #ftir?#analysis?#plastics?#polymerscience?#materialsscience?#spectroscopy??#chemistry

When faced with the challenge of understanding the unique morphology and filler content of a graphite-filled plastic, I turned to two powerful analytical techniques: scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). Recently, I worked on the evaluation of a component made from a unique plastic resin: a graphite-filled thermoplastic polyimide (TPI). My curiosity about the material's morphology led me to create a controlled laboratory fracture through mechanical overload. To understand the fracture surface, I used scanning electron microscopy (SEM). At magnifications over 750X, the graphite flakes became clearly visible. The optimal magnification to observe the base polymer and graphite interface was approximately 3000X. To determine the graphite filler content, I utilized thermogravimetric analysis (TGA). The resulting TGA thermogram revealed a weight loss in nitrogen, centered at approximately 600°C, accounting for 35%, which represented the initial and partial decomposition of the polymer. When the atmosphere was switched to air and the samples ww heated to elevated temperatures, a total weight loss of 64% was observed over a broad range from 550°C to 850°C. The derivative curve showed a bimodal weight loss pattern, indicating the combustion of the char formed during the initial polymer decomposition, followed by the combustion of the graphite filler itself. Given the structure of polyimide, approximately equal weight losses are expected in nitrogen and air. From these results, the graphite content in the material was estimated to be around 30%. This evaluation illustrates the power of combining the exceptional visual capabilities of SEM with the precise quantitative abilities of TGA to characterize filled or reinforced polymers. If you're interested in learning more about how these techniques can be applied to your materials or products, feel free to reach out, [email protected].

Free consulting? MAI offers consulting services for $245/hour with one of our metallurgical engineers. If the consultation results in a project for MAI, we will refund the first hour of the consulting fee on the project invoice. The purpose of Metallurgical Associates, Inc. is to solve our clients' materials-related problems.?These problems range from the basic, such as a chemical analysis to confirm that a vendor has provided the correct material, to the complex, such as a comprehensive failure analysis with possible litigation consequences. Another service MAI provides our clients is consulting. MAI offers consulting services regarding Manufacturing Troubleshooting for: ???????????-Machining, forging, and casting problems ???????????-Forming, extruding, drawing, and powder metal problems ???????????-Heat treating problems of all types ???????????-Welding, brazing, soldering, and cutting problems of all types ???????????-Plating, painting, and coating problems of all types And . . . Product Improvement and Cost Reduction for: ???????????-Materials selection and substitution ???????????-Development of heat treating procedures ???????????-Development of welding and other joining procedures ???????????-Plating, painting, and coating selection ???????????-Design as related to materials, and weld and braze joint configuration Not sure where to go for your metallurgical related questions? Contact MAI today to schedule your consultation. 262-798-8098 [email protected] #mai #metallurgy #failureanalysis #consulting #metals

In Person or Remote SEM/EDS sessions available next week! Please contact MAI today to schedule your session 262-798-8098 or [email protected]. #mai #SEM #failureanalysis #tescan #EDS #metallurgy #metallurgicalengineering

This Day in History! In an effort to make gun barrels resistant to rust, Harry Brearley experimented with different alloys and added 12.8% chromium to molten iron to create the first "rustless" steel. The name eventually changed from "rustless" to stainless steel and was both rust and corrosion resistant. What is interesting is that this new steel alloy was used to manufacture medical instruments, silverware for mess kits, and aircraft engines in World War I, it was not used for manufacturing guns. Brearley was twelve years old when he left school to work with his father, who was a steelworker. In the same company, Brearley worked his way into the chemical lab. He continued to work at the same company, but studied at home and took evening classes in an effort to specialize in both steel production techniques and chemical analysis methods (according to Wikipedia). According to most articles, his effort to produce the first "rustless" steel was a mistake . . . a mistake that would help shape our world! #mai #metallurgy #stainlesssteel

Real metals in the medals! Great explanation by Sarah Jordan.