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  Today's KNOWLEDGE Share: LCA: Have you ever thought that life cycle assessment (LCA) is a bit of a minefield? Let’s start with a cup of tea! Whether you want to benchmark your product against another, find the hotspots in your supply chain or comply with your customer’s Environmental Product Declaration (EPD) requirements, understanding the basics of LCA methodology is increasingly important to avoid greenwashing. Source:Enrique J Garcia

  Today's KNOWLEDGE Share: Carbon fiber 3D woven joints 3D woven joints and preforms are widely used in aircraft, missiles, satellites, spacecraft, helicopters, vehicles and more. By means of the low cost, fast production and lightweight solutions, 3D woven carbon fiber composites are the products of the present and the future! What are the advantages of using 3D woven composites, instead of common 2D laminated composites? - They can be directly woven into complex net shapes - Allows higher fiber volume - Improved impact resistance and Compression After Impact - Yarns can be controlled according to stability, strength and shape desired in the end product - Possibility to choose different fiber types such as carbon fiber, aramid, glass etc. in the weaving process - Practically zero delamination between the layers - Reduce the cost of composite parts production Source: Erginer Ceramic and Composites Technology/# managingcomposites

  European Chemicals Agency (ECHA) adds nine chemicals in the Candidate List because of their hazardous properties. They are used for example in flame retardants, paints and coatings, inks and toners, coating products, plasticizers and in the manufacture of pulp and paper. 233 Entries in the Candidate List: ECHA’s Member State Committee confirmed the addition of these substances to the Candidate List. The Candidate List now has 233 entries – some are groups of chemicals, so the overall number of impacted chemicals is higher. These substances may be placed on the Authorisation List in the future. If a substance is on that list, its use will be prohibited unless companies apply for authorization and the European Commission authorizes them to continue its use. Entries added to the Candidate List on 17 January 2023 are as follows: 1) 1,1'-[ethane-1,2-diylbisoxy]bis[2,4,6-tribromobenzene] 2) 2,2',6,6'-tetrabromo-4,4'-isopropylidenediphenol 3) 4,4'-sulphonyldiphenol 4) Ba...

  Today's KNOWLEDGE Share: Reinforcements: What is the effect of reinforcement type on the strength properties of fiber reinforced composites? This insightful graph shows how different reinforcements (like short fibers, mats, fabrics, and unidirectional fibers) can increase the strength properties of composite materials! Source:managingcomposites

  Today's KNOWLEDGE Share: TGA Thermogravimetric analysis (TGA) is a common thermal analysis technique that provides composition information for polymeric materials. Most often, we associate TGA with quantitative data. However, I was reminded during a recent material analysis that TGA can also provide insight into the qualitative analysis. I was analyzing a rubber O-ring. My first test, as usual, was Fourier transform infrared spectroscopy (FTIR). The FTIR indicated that the material was a nitrile rubber (NBR) compound. Additional absorption bands associated with aluminum silicate clay were also present. Weak bands indicated an ester-based plasticizer. The general form of the spectrum was suggestive of a moderate loading of carbon black. I conducted the TGA analysis and found all of the expected weight loss events for the quantification of the plasticizer, polymer, and carbon black, as well as the residue for the mineral filler. However, one additional weight lo...

  Today's KNOWLEDGE Share: Geometric lattice cores When talking about geometric lattice cores, most people think about a core with hexagon shaped cells, which is the basic and most common cellular honeycomb configuration. However, we have other options currently available on the market, such as Flex-Core, Ox-Core and Double-Flex to name a few! But how to select between them? The Flex-Core cell configuration provides for exceptional formability in compound curvatures with reduced anticlastic curvature and without buckling the cell walls. Curvatures of very tight radii are easily formed. When formed into tight radii, Flex-Core provides higher shear strengths than comparable hexagonal core of equivalent density. The “OX” configuration is a hexagonal honeycomb that has been over-expanded in the “W” direction, providing a rectangular cell configuration that facilitates curving or forming in the “L” direction. The OX process increases “W” shear properties and decreases “L” shear properti...

  Today's KNOWLEDGE Share: Which was the first composite material manufactured by humans?  As you may already know, a composite material is, by definition, ''a material that is made of two or more different materials, differentiable at a microscopic level, whose specific properties are better than their separated properties''.  Just like any topic related to discovering the first application of any new technology, there is still some debate about which was the first composite material developed by humankind. The answer heavily depends on your own interpretation of the definition aforementioned, and also the reliability when dating ancient discoveries.  Many researchers point out that the first uses of composites date back to 1500 B.C. when early Egyptians and Mesopotamian settlers used a mixture of mud and straw to create strong and durable buildings. The mud acted as a matrix for the random straw reinforcements! Mesopotamians also used straw to provide reinforcemen...

  Today's KNOWLEDGE Share:  Composite Essentials!  What are the most common failure modes for carbon fiber composites? Let's check them out in detail!  This microscopy shows three different failure modes: delamination, tensile fiber fracture, and tensile/shear matrix cracks in a cross-ply laminate! Fracture analysis when zoomed-in can reveal a lot of info to engineers!  Bibliographical Reference: Article ''On the Effective Constitutive Properties of a Thin Adhesive Layer Loaded in Peel'', written by Andersson T and Biel A. Source:managingcomposites/thenativelab

  Today's KNOWLEDGE Share: Composite Essentials Let's learn more about the different weave patterns in woven fabrics! Woven fabrics are woven yarns, rovings, or tows in mat form in a single layer, in which the amount of fiber in different directions is controlled by the weave pattern. The most common are Plain, Twill and Harness Satin!  In a plain-weave pattern, fibers in 0° and 90° directions are equally distributed. A plain weave carbon fiber sheet looks symmetrical with a small checkerboard style appearance. In this weave the tows are woven in an over/under pattern.  In a twill weave, the tow strand passes over a set number of tows and then under the same number of tows. The over/under pattern creates a diagonal arrowhead look, known as a “twill line”. 2×2 Twill is likely the most recognizable carbon fiber weave in the industry. It is used in many cosmetic and decorative applications, but also has great functionality, it has both moderate formability and moderate stabi...