How can multilayer structural parts significantly improve bending and compressive stiffness while reducing weight?
Publish Time: 2025-12-17
In the field of high-end equipment manufacturing, lightweighting is never simply about "thinning" or "hollowing out" materials, but rather about achieving optimal material distribution while ensuring or even improving structural performance. Multilayer metal structural components, especially those manufactured using superplastic forming and diffusion welding (SPF/DB) composite processes, are outstanding examples of this concept. One of their core secrets lies in whether biomimetic topological structures such as internal reinforcing ribs, honeycomb, or lattice cores can significantly improve bending and compressive stiffness while substantially reducing weight.Traditional solid or single-layer plate structures often sacrifice strength for thickness, but this also means unnecessary mass accumulation. Multilayer structural parts take a different approach: they resemble bones or plant stems in nature—seemingly slender on the outside, but filled with a sophisticated support network inside. By constructing three-dimensional periodic lattices, corrugated reinforcing ribs, or closed cavities between the upper and lower skins, a mechanical system that is "hollow yet not empty, light yet with bone" is formed. When external loads are applied to the surface, these internal structures rapidly distribute the force across the entire cross-section, effectively suppressing local buckling and deformation. Especially under bending or compression conditions, the core acts like countless miniature pillars, working together to resist instability, resulting in overall stiffness far exceeding that of solid materials of the same weight.The advantages of this design are not only reflected in static strength but also demonstrate its value in dynamic environments. For example, in aircraft wings or satellite supports, structures must simultaneously withstand aerodynamic loads, vibrations, and thermal cycling. The multi-layered lattice core, due to its high specific stiffness and energy absorption characteristics, effectively suppresses resonance, buffers impacts, and maintains geometric stability. All of this is accomplished without adding extra parts or connectors—the entire structure is integrally formed from one or more metal sheets, without rivets or welds, avoiding stress concentration and failure risks associated with traditional assembly.Even more commendable is that this lightweight yet strong characteristic does not come at the expense of surface quality. The SPF/DB process, under high temperature and pressure, causes metal to flow slowly and bond at the atomic level. The resulting outer surface is smooth and continuous, requiring almost no subsequent polishing. This preserves the integrity of the material's surface while meeting stringent requirements for aerodynamic shape and aesthetic appearance. For components requiring integrated fluid channels or heat dissipation, internal cavities can be cleverly designed as functional pathways, achieving a high degree of integration where "structure is system."From an engineering philosophy perspective, the design thinking behind multilayer structural parts is essentially a pursuit of ultimate efficiency—using the least amount of material to support the greatest functionality. It rejects redundancy and advocates intelligent distribution; it doesn't rely on haphazard stacking but on structural wisdom to succeed. This philosophy perfectly aligns with the common demands of aerospace, new energy equipment, and even high-end medical devices for high performance, low energy consumption, and long lifespan.Ultimately, whether multilayer structural parts achieve a balance between lightweight and high rigidity through internal reinforcing ribs or lattice cores is not a theoretical assumption, but rather a successful convergence of advanced materials science and biomimetic structural design in real-world engineering. It allows metal to "breathe," nurturing strength within its gaps; it enables structures to "think," achieving greater strength while reducing weight. This is not only a leap in manufacturing technology, but also a vivid manifestation of humanity learning from nature and harnessing the wisdom of matter.
