LIBS in Quality Control of plastic components

In the modern industrial landscape, quality control and material verification are crucial for maintaining standards and ensuring product safety. The automotive industry is one of the most demanding sectors for quality control due to its strict quality standards, the large volume of materials involved, and the cost of poor quality being very high. Additionally, the time available to ensure quality before products move to the next process step is very limited. Here is where not only the speed but also other advantages of Laser-Induced Breakdown Spectroscopy (LIBS) come into play. This advanced technology offers a fast, accurate, and micro-destructive method for analysing the elemental composition of all kinds of materials.

Our customer received a delivery of one batch of elastomer components. Within one batch he noticed the difference in colour shade and also different flexibility by touch. The products were too small for standard tensile testing and the shape was not suitable for impedance tests either. That’s why he contacted us to help him detect the differences. We agreed to examine if there is any difference in the chemical composition of 2 products of the same batch. Performing this analysis with our M-Trace easily proved the presence of high titanium content in one sample, which explained differences in color and also lower flexibility. Our customer had to reject the delivery, but by doing so he saved significant money that claim processing would cost if such products get through to the next steps in his value chain.

Titanium is often added to plastics to enhance their properties, such as increasing durability, improving UV resistance, or providing a bright white colour in the form of titanium dioxide (TiO2). Furthermore, it can also be present as a residuum from Ziegler-Natta catalysts, which are used to initiate the polymerization process.

However, what seems a little bit more challenging is to determine whether the titanium originates from a catalysator or an additive. Another customer wanted to confirm the purity of a transparent plastic sample; he was suspicious about possible contamination from moulding land catalyst residues. To deal with this issue, a thorough investigation of samples was needed. The presence of the Ziegler-Natta catalyst can also be proved by the trace presence of aluminium or magnesium in the sample, both of which LIBS is a very sensitive technique for detecting. Additionally, the intensity of the oxygen peak can provide valuable insights. To eliminate interference from oxygen in the air, the measurement must be conducted in an inert atmosphere. 

Our M-Trace offers an ideal solution, equipped with a vacuum capsule that allows precise regulation of the atmosphere. Of course, it is also necessary to keep in mind that some types of polymers contain oxygen in their monomeric structure or indigenous from some other additives. For this problem reference samples serve as invaluable tools, enabling the comparison of oxygen signals between unknown and reference samples. Employing this LIBS device and its features we could assure the customer that the samples are free of Ti or TiO2.

In conclusion, both customers were highly satisfied as we have efficiently and effectively dealt with their issues in quality control. As proven, our devices bring solutions even to challenging tasks, thanks to their exceptional sensitivity and the advanced capabilities of accompanying equipment. The advantages of LIBS technology extend beyond titanium detection, making it an indispensable tool for efficient quality checks at every gate of the production process across various fields, from plastic to glass, ceramics, rubber, minerals and more. 

If you have similar difficulties and insecurities about the products you employ or produce, do not hesitate to contact us