Effects of Impact Velocity and Stress Concentrators in Titanium on Failure by Adiabatic Shearing
Abstract
This Final Technical Report covers the contract period from Sept. 24/1998 to Nov. 11/1999. A more detailed information on the progress of this Contract can be found in the previous Interim Reports. During the period under consideration the research was directed toward effects of impact velocity and stress concentrators in titanium alloy Ti-6Al-4V on failure by adiabatic shearing. A series of experiments has been performed on Modified Double Shear specimens (MDS technique) with a square notch (standard geometry). A wide range of strain rates in shear has been applied from 10(E)-4 1/s to 10(E)5 1/s. The MDS specimens were loaded by a fast hydraulic machine up to strain rate 10(E)2 l/s and by technique of the direct impact with the maximum impact velocity 100 m/s. It has been found that the failure occurs in this alloy by adiabatic shear banding. The fracture surfaces were analyzed by Scanning Electron Microscopy (SEM). The test results were used to identify material constants in an improved constitutive relation with rate and temperature dependent flow stress. This relation was applied in the FE Code ABAQUS together with a failure criterion based on the Critical Impact Velocity in shear (CIV).
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1999
- Accession Number
- ADA378515
Entities
People
- J. R. Klepaczko