Impact damage characteristics of carbon fibre metal laminates : experiments and simulation

In this work, the impact response of carbon fibre metal laminates (FMLs) was experimentally and numerically studied with an improved design of the fibre composite lay-up for optimal mechanical properties and damage resistance. Two different stacking sequences (Carall 3–3/2–0.5 and Carall 5–3/2–0.5) were designed and characterised. Damage at relatively low energy impact energies (≤30 J) was investigated using Ultrasonic C-scanning and X–ray Computed Tomography (X-RCT). A 3D finite element model was developed to simulate the impact induced damage in both metal and composite layers using Abaqus/Explicit. Cohesive zone elements were introduced to capture delamination occurring between carbon fibre/epoxy plies and debonding at the interfaces between aluminium and the composite layers. Carall 5–3/2–0.5 was found to absorb more energy elastically, which indicates better resistance to damage. A good agreement is obtained between the numerically predicted results and experimental measurements in terms of force and absorbed energy during impact where the damage modes such as delamination was well simulated when compared to non-destructive techniques (NDT)

Development of sintered con-rods for automotive engines

Within an international research program con-rods from the alloy Fe-1.5-Cu-0.6C, quenched and tempered, with densities mostly over 7.0 g/ccm in the highly stressed areas were developed and pressed in the single sintering technique. The PM' tooling for the compaction-sinter-size route was manufactured after extensive FEM and experimental stress analyses. After successful fatigue testing, the con-rods achieved final engine testing without any failures. The duration corresponded to 150.000 to 300.000 km normal european operational service