An investigation was conducted into the microstructural analyses of the surface layer hardened by the irradiation of high-energy electron bean in a 0.38% C plain carbon steel. Steel specimens were irradiated using an 1.4 MeV electron accelerator, and the microstructures of the irradiated surface layers were examined. The ferrite-pearlite structure ...
10 volume% ZrO2 reinforced NiAl matrix composite(ZrO2/NiAl) was prepared by reactive hot-pressing of elemental powders. Mixtures of Ni and Al powders with reinforcing particles of partially stabilized ZrO2 have been ball-milled and hot pressed at 980 degrees C under 30 MPa. The hot-pressed billets were extruded at 1200 degrees C with an extrusion r...
10 volume% ZrO2 reinforced NiAl matrix composite(ZrO2/NiAl) was prepared by reactive hot-pressing of elemental powders. Mixtures of Ni and Al powders with reinforcing particles of partially stabilized ZrO2 have been ball-milled and hot pressed at 980 degrees C under 30 MPa. The hot-pressed billets were extruded at 1200 degrees C with an extrusion r...
10 volume% ZrO2 reinforced NiAl matrix composite(ZrO2/NiAl) was prepared by reactive hot-pressing of elemental powders. Mixtures of Ni and Al powders with reinforcing particles of partially stabilized ZrO2 have been ball-milled and hot pressed at 980 degrees C under 30 MPa. The hot-pressed billets were extruded at 1200 degrees C with an extrusion r...
10 volume% ZrO2 reinforced NiAl matrix composite(ZrO2/NiAl) was prepared by reactive hot-pressing of elemental powders. Mixtures of Ni and Al powders with reinforcing particles of partially stabilized ZrO2 have been ball-milled and hot pressed at 980 degrees C under 30 MPa. The hot-pressed billets were extruded at 1200 degrees C with an extrusion r...
The in situ crack opening displacement (GOD) with respect to the distance behind the stationary crack tip was measured in three alumina ceramics with different grain size. An analytical model which can describe the relationship between the bridging stress and the microstructure and a double cantilever beam (DCB) analysis which includes the bridging...
A study has been made to investigate boundary sliding and its accommodation mode with respect to the variation of grain size and alpha/beta volume fraction during superplastic deformation of a two-phase Ti-6Al-4V alloy. A load relaxation test has been performed at 600 degrees C and 800 degrees C to obtain the flow stress curves and to analyze the d...
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Grain refinement of a superplastic 7475 Al alloy is observed at strain rates of 10(-2)s(-1) or higher. Metallographic observation shows that the average grain size is changed from 14 mu m to 10 mu m after 100% elongation. Two-stage strain-rate tests were performed on the 7475 Al alloy to correlate grain refinement with an improvement of superplasti...
Theoretical approaches are made in the present study to improve a former fatigue crack growth (FCG) model based on the conception of the local damage accumulation. A new da/dN-Delta K relationship is derived which predicts the stage-II FCG behavior independently from the basic low cycle fatigue properties. A satisfactory agreement is found between ...
