THIRD-DIMENSIONAL DUCTILITY AND CRACK PROPAGATION IN BERYLLIUM SHEET

Technical Report · Wed Mar 18 04:00:00 EST 1959

OSTI ID:4286982

Yans, F M

Uniaxial tensile elongations of approximately 20 to 30% were previously achieved in Be sheet fabricated by extrusion and transverse rolling. A new fabrication process was developed whereby the material derived has a good measure of third dimensional ductility, yet allows uniaxial tensile elongations of 15 to 20%; moreover, this material fractures in a completely isotropic fashion, ellruinating crack propagation to a very significant degree. This new sheet is made by a process called upsetting, that is, by applying purely compresslve forces along the longitudinal axis of a cyllodrical Be billet consisting of cold- compacted Re powder inside a steel can. The texture resulting from this operation is the key to the advantageous change in mechanical properties. Pn respect to the plane of the sheet, the (O001) planes are oriented mainly parallel and the (1120) planes transverse, but randoru with respect to any direction within the plane. The third dimensional ductility of sheet prepared in three different ways, upset, extruded and transverse-rolled, and hot-pressed, was investigated by performing bend tests on specimens with varying width-to- thickness ratios. In each case, the upset sheet exhibited better third dimensional ductility and strengths under complex stress. The fabrication was performed at 1850 F. 125 sheets were made by this technique with a 97% yield. (auth)

• Research Organization: Nuclear Metals, Inc., Concord, Mass.
• NSA Number: NSA-13-010039
• OSTI ID: 4286982
• Report Number(s): NMI-1212
• Country of Publication: United States
• Language: English

Related Subjects

ANISOTROPY
BERYLLIUM
COLD WORKING
COMPACTING
CONFIGURATION
CRACKS
CYLINDERS
DUCTILITY
EFFICIENCY
EXTRUSION
FABRICATION
FAILURES
HIGH TEMPERATURE
HOT WORKING
LATTICES
MECHANICAL PROPERTIES
METALLURGY AND CERAMICS
POWDERS
PRESSURE
RODS
ROLLING
SHEETS
STEELS
STRESSES
TENSILE PROPERTIES
THICKNESS
VESSELS