The mechanical behavior of 316LVM 1×7 cables were evaluated in uniaxial tension, and in cyclic strain-controlled fatigue with the use of a Flex tester operated to provide fully reversed bending fatigue. The magnitude of cyclic strains imparted to each cable tested was controlled via the use of different diameter mandrels. Smaller diameter mandrels produced higher values of cyclic strain and lower fatigue life. Multiple samples were tested and analyzed via scanning electron microscopy. The fatigue results were analyzed via a Coffin-Manson-Basquin approach and compared to fatigue data obtained from the literature where testing was conducted on similar materials, but under rotating bending fatigue conditions.

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The effects of mixed mode loading on the fracture behavior of Zr-based bulk metallic glasses (BMGs) (Vitreloy I and Vitreloy 106) were investigated. Mixed mode I/II and mixed mode I/III fracture conditions were tested using both notched and fatigue-precracked specimens. Fully amorphous samples exhibited tremendous increases in fracture energy with the application of mixed mode loading, while partially crystalline samples exhibited more modest increases. A comparison to the behavior of other material systems (e.g., polymers, ceramics, crystalline metals, and composites) illustrates the tremendous increase in fracture energy exhibited by these BMGs under mixed mode loading conditions.

The effects of wide changes in stress state on the flow and fracture behavior of a single Zr-Ti-Ni-Cu-Be bulk metallic glass (BMG) of known chemistry are summarized. Both compression and tension samples were tested with superimposed hydrostatic pressures up to 1230 MPa in addition to notched tension samples tested at 0.1 MPa as well as with 490 MPa superimposed pressure. A wider range of stress states were obtained by including compression experiments conducted in pressure/shear conditions with normal stresses up to 8.7 GPa. The critical shear stress at fracture in the present BMG chemistry and sample dimensions tested is relatively unaffected by these significant changes in stress state, again indicating the normal stress/pressure dependence of flow in this particular BMG chemistry and processing conditions is vanishingly small. The present results are compared to those obtained on other metallic glasses tested under similar conditions and those that exhibit inclusion-initiated failure that demonstrate a much different dependence for similar changes in stress state.

Fracture of Ultra High Molecular Weight Polyethylene (UHMWPE) components used in total joint replacements is a clinical concern. UHMWPE materials exhibits stable crack growth under static loading, therefore, their fracture resistance is generally characterized using the J-R curve. The multiple specimen method recommended by ASTM for evaluation of the J-R curve for polymers is time and material intensive. In this study, the applicability of a single specimen method based on load normalization to predict J-R curves of UHMWPE materials is evaluated. The normalization method involves determination of a deformation function. In this study, the J-R curves obtained using a power law based deformation function and the LMN curve based deformation function were compared. The results support the use of the power law based deformation function when using the single specimen approach to predict J-R curves for UHMWPE materials.