Irreversible deformation processes in PVC and its short glass fiber reinforced composites

Thesis/Dissertation · Tue Jan 01 00:00:00 EST 1985

OSTI ID:5284226

Yuan, J Y

The tensile mechanical behavior of PVC and its short glass fiber reinforced composites under superimposed hydrostatic pressure was studied up to 3 x 10/sup 8/ Pa. For rigid PVC, the brittle-to-ductile transition was observed at a pressure between 1 x 10/sup 7/ Pa and 2 x 10/sup 7/ Pa. This pressure-induced brittle-to-ductile transition was controlled by the competitive microdeformation processes of crazing and shear banding. Deformation in the post-yield region occurred by neck formation and subsequent drawing to produce chain orientation. A strong environmental stress-cracking effect was observed when PVC samples were exposed to the pressure-transmitting fluid, silicone oil. Three types of pressure dependent deformation processes was observed for the short glass fiber reinforced composites of PVC. Type I behavior shows debonding at the interface between fiber and matrix followed by brittle fracture of the matrix. Type II behavior, which was observed for the first time, exhibits a sharp stress drop due to debonding at the interface followed by matrix shear yielding. In Type III behavior, only upper shear yielding of matrix was observed. The transitional behavior from Type I and Type II was controlled by the pressure induced brittle to ductile transition of the matrix, while the Type II-III transition was strongly affected by debonding at the interface.

• Research Organization: Carnegie-Mellon Univ., Pittsburgh, PA (USA)
• OSTI ID: 5284226
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
COMPOSITE MATERIALS
BRITTLE-DUCTILE TRANSITIONS
DEFORMATION
FIBERS
PRESSURE EFFECTS
PVC
CHLORINATED ALIPHATIC HYDROCARBONS
HALOGENATED ALIPHATIC HYDROCARBONS
MATERIALS
ORGANIC CHLORINE COMPOUNDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC POLYMERS
POLYMERS
POLYVINYLS
360303* - Composite Materials- Mechanical Properties- (-1987)