1 / 11

Spall Fracture of Multi-Material Plates Under Explosive Loading

Spall Fracture of Multi-Material Plates Under Explosive Loading. Engineering Project Second Progress Report Presentation By James Danyluk. Spall Fracture in Solids. Shock waves traveling through a solid material is reflected at changes in material or free surfaces.

conroy
Télécharger la présentation

Spall Fracture of Multi-Material Plates Under Explosive Loading

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Spall Fracture of Multi-Material Plates Under Explosive Loading Engineering Project Second Progress Report Presentation By James Danyluk

  2. Spall Fracture in Solids • Shock waves traveling through a solid material is reflected at changes in material or free surfaces. • These reflected shock waves are known as rarefaction waves or relief waves. • When a free surface and rarefaction wave interact, a tensile stress can be generated in the solid material. • This can also happen with two rarefaction waves interact. • If this tensile stress exceeds the dynamic tensile strength, or spall strength, the material can fracture.

  3. Hydrocode Model • ANSYS AUTODYN, an explicit dynamics code, was used to model the system. • The Euler Multi-material solver was used. • The model was setup with an Explosive, Solid Material and Air layers. • The analysis modeled different materials and material combinations • The tensile wave generated in the solid material(s) was examined in each model. • The analysis was separated into four sets of iterations • 1D Elastic only material models • 1D Elastic/Plastic material models • 1D Elastic/Plastic/Failure material models • 2D Elastic/Plastic/Failure material models

  4. Hydrocode Model Single Plate Model Two Plate Model Three Plate Model

  5. Single Plate Hydrocode ResultsAl6061-T6 Plate

  6. Single Plate Hydrocode Results Shock wave in explosive Shock wave in plate Rarefaction wave generated

  7. Two Plate Results Tungsten/Polyethylene Combination Tungsten/304L Steel Combination

  8. Three Plate Results Tungsten/Polyethylene/Tungsten 304L/Tungsten/304L

  9. Spall Failure Model Results Tungsten/Aluminum Aluminum/Tungsten

  10. Current Conclusions • Stacking materials can dictate how spall failures occur • For most cases, the outer solid layer developed spall planes, while the inner layer remained intact. • This method can be used to develop “spall plates”, plates that are intentionally designed to spall off, leaving the desired material (inner layer) intact. • When a highly dense material (tungsten) is mated next to a very low density material (aluminum, polyethylene), a rarefaction wave can be generated by the material interface that will cause the tungsten plate to spall. • Other material combinations did produce rarefaction waves, but they were not large enough to overcome the explosive loading and produce a tensile stress in the plate. • In these cases, the spall can happen in both the inner and outer layers, but the amount of spall is highly reduced in the outer layer.

  11. Schedule/Milestones • 9/21/10: Submit Proposal • 9/28/10: Complete Hand Calculations/Finish Research • 10/5/10: Complete 1-D Elastic Hydrocode Model Results • 10/12/10: Complete 1-D Elastic/Plastic Hydrocode Model Results • 10/19/10: Submit First Progress Report • 10/26/10: Complete 1-D Elastic/Plastic/Failure Hydrocode Model Results • 11/9/10: Submit Second Progress Report • 11/18/10: Complete 2-D Elastic/Plastic/Failure Hydrocode Model Results • 11/30/10: Submit Final Draft • 12/14/10: Submit Final Report

More Related