Tearing during pinch-off of Rolamite fill tubes

Technical Report · Sun Nov 01 00:00:00 EST 1981

DOI:https://doi.org/10.2172/5712419· OSTI ID:5712419

Yost, F. G.

A failure mechanism is proposed to explain the bubble streaming and trichloroethylene infiltration which has been observed in failed Rolamite devices. An intergranular oxide network forms in the Kovar fill tube as a result of the glass-to-metal seal processing; it is suggested that tearing occurs in this oxide network during a subsequent pinching-off operation. It is demonstratd that bending over a mandrel causes this intergranular network to widen and deepen in a tearing mode. A modified preoxidation heat treatment or partial oxidation procedure prevents this problem.

• Research Organization: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 5712419
• Report Number(s): SAND-81-1952; ON: DE82006873
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
KOVAR
FABRICATION
FRACTURE PROPERTIES
FAILURES
OXIDATION
STRESSES
TUBES
ALLOYS
CHEMICAL REACTIONS
COBALT ALLOYS
IRON ALLOYS
IRON BASE ALLOYS
MANGANESE ADDITIONS
MANGANESE ALLOYS
MECHANICAL PROPERTIES
NICKEL ALLOYS
360101* - Metals & Alloys- Preparation & Fabrication
360102 - Metals & Alloys- Structure & Phase Studies