Elasticity Approach — Lesson 2

This lesson covers the micro mechanics of Lamina, focusing on the determination of elastic modules and string parameters of fiber composites. It delves into the different approaches for determining these parameters, with a special emphasis on the mechanics of material approach. The lesson also discusses the role of the matrix in the longitudinal strength of Lamina. It explains how the strength of fibers embedded into a matrix is almost twice that of dry fibers, attributing this to the statistical distribution of fiber strength. The lesson further explores the elasticity approach to explain the tensile longitudinal tensile strength and longitudinal compression strength of a lamina.

Video Highlights

02:56 - Analysis of the strength of fibers embedded into a matrix
05:39 - Concept of cumulative fiber breakage
07:36 - Explanation of the Shear leg model
39:00 - Strain energy stored in the fiber and the matrix
46:30 - Critical compression stress

Key Takeaways

- The matrix plays a significant role in the longitudinal strength of Lamina. It acts as a binder and also transfers load among fibers.
- The strength of fibers embedded into a matrix is almost twice that of dry fibers. This is attributed to the statistical distribution of fiber strength.
- The elasticity approach provides a comprehensive understanding of the tensile longitudinal tensile strength and longitudinal compression strength of a lamina.
- The fibers in a lamina can buckle in two distinct modes - extension mode and shear mode. The matrix resists this buckling by experiencing tensile strain or shear strain.