This guest contribution on Innovation Intelligence is written by Edouard Ferry, Engineer at CEDREM. KTex Family is available through the Altair Partner Alliance.
Composite materials have the potential to change the way we manufacture parts as we know it, due to their contribution to creating lighter structures with the same stiffness, resulting in cost reductions. However, composites are complex, not only in terms of mechanical properties, but also in terms of manufacturing processes, so it is important to consider all possibilities when developing new products involving them. Many materials and variations in how composite fibers are bound, (i.e. in matrix, stitching, or weaving forms, etc.) results in many different manufacturing processes available, but also many things to consider, because every step in the manufacturing process and every environmental factor has an influence on how the material will turn out.
Another challenge affecting development of composites lies in that defects (such as porosity or delamination) are invisible from the outside, but might result in severe part failures. In this scenario, numerical simulation could be of great help because many different configurations can quickly be tested, and virtual cross-sections inside the material can be performed. However, in order to study such phenomena, numerical models of composite materials at the scale of the yarns must be built in order to represent any and all kinds of weaving patterns (uni-directional, NCF, 2D, 3D, etc.). Manufacturing processes need to be represented in these tests in order to study the behavior of composite materials as well as to predict their impact on the performance of the final part. A full validation and optimization approach could then be led.
CEDREM possesses defense, safety and security simulation expertise, even recently initiating the creation of the Radioss Club Defense Safety and Security (RCDSS) in France, a regular meeting for HyperWorks users with interests in these fields.
To address and combat many of the concerning factors surrounding the development of composite parts, CEDREM has recently developed the KTex Family tools to simulate the material behaviors at the scale of the yarns.
KTex Pattern aims to represent any composite ply, whether unidirectional, NCF, 2D or 3D, with any fiber and matrix material.
KTex LayUp helps the user set up a finite element model simulating the lay-up process of any given composite ply on any given shape. From this simulation, the user can analyze how the orientation between the fibers has changed, how the fiber volume fraction has been modified, etc. Updated mechanical properties can be derived from this information and assigned to the different areas of the final part to represent areas of weakness more precisely.
KTex Winding is developed to simulate the winding process, with such specificities as winding angle, ribbon dimensions, winding pattern, etc. Here again, the output will be a finite element model taking into account the discrepancies introduced during the manufacturing phase.
Finally, KTex WovenProperty is a homogenization tool enabling the user to calculate the macroscale homogenized mechanical properties of any given composite weave. After describing the weave characteristics (yarns dimensions, material, spacing, weaving patterns, etc.), the user will obtain the mechanical properties (Young’s modulus, Shear Modulus and Poison’s ratios in the three directions) of the described weave.
With these tools, the accurate mechanical properties of any composite material can be calculated. It is even possible to predict how the manufacturing process will impact these properties and where. Hence, numerical models become more representative of reality, and products performance is more precisely assessed and optimized.
If you want to learn more, please visit altairhyperworks.com/partner/ktex-family.