PREPARATION AND EVALUATION OF HIGH PURITY BERYLLIUM. Bi-Monthly Progress Report, January 2-March 1, 1961

Technical Report · Tue Oct 31 04:00:00 EST 1961

OSTI ID:4057401

Spangler, G E; Herman, M

Two single crystals of beryllium with the basal plane tilted -20 and 45 deg , respectively, were subjected to eight zone refining passes which resulted in sufficient curvature to make funther melting difficult. A specimen of the 20 deg crystal underwent, without fracture, a l8O deg bend about a radius approx equal to its diameter, 0.112 in. A specimen of the 45 deg crystal was tested to fracture in tension, and exhibited a 156% glide strain on the basal plane, equivalent to 92% elongation. Comparison of the critical resolved shear stress for basal slip of the 45 deg crystal, 520 psi, with previously reported values suggests that the observed increase in ductility is the result of a decrease in the impurity concentration. The orientation of a third crystal, tested in tension, was such as to produce the duplex slip on (1010) planes. The resolved shear stress on the basal plane at yielding was -2000 psi. A 40% over-all elongation was produced with rather severe localized necking to almost a kife- edge fracture. (B.O.G.)

• Research Organization: Franklin Inst. Labs. for Research and Development, Philadelphia
• NSA Number: NSA-15-014721
• OSTI ID: 4057401
• Report Number(s): NP-9986; P-A2476-2
• Country of Publication: United States
• Language: English

Related Subjects

BERYLLIUM
CRYSTALS
DUCTILITY
FAILURES
IMPURITIES
MATERIALS TESTING
MELTING
METALS, CERAMICS, AND OTHER MATERIALS
QUANTITY RATIO
REFINING
TENSILE PROPERTIES
ZONES