QUARTERLY REPORT OF TECHNICAL PROGRESS NO. 7
Abstract
Preliminary results have been obtained from a computer program that predicts strains in a circular blank forced into an ellipsoidal die. For the first time, the analysis accounts for flange pull-in directly. The program will provide useful information in selecting blank dimensions for specific applications and will reduce the amount of sub-scale testing required. Stabilizing the edge of blanks by a chevron ring pattern engaging a welded rim has been shown to reduce the scatter in strain distribution for parts formed into a die. This is especially important for material that work-hardens during forming and for parts that must be chem-milled after forming. Initial tests indicate that useful data can be read during explosive forming from strain gages attached to the blank even though the gages do not survive the entire forming process. All single-shock aluminum specimens have been shock-hardened and selected multiple-shock tests are underway. Displacement-time data for expanding ring strain-rate measurements are being differentiated using a least- squares computer subroutine.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1967
- Accession Number
- AD0651318
Entities
People
- Gaylen A. Thurston
Organizations
- Martin Marietta