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lead to the long slip path in the Ti-B20 specimens treated by beta solution plus aging. The high stress concentration and local strain occur at the grain boundary especially at triple points. In these regions, crack initiates and propagates along grain boundaries and fracture occurs even at low macroscopic strains. As a result, low tensile ductility appears. Fig.3 Comparison of microstructure......
temperature silicon is inherently brittle and that there is no dislocation activity at the crack tip. Fig.3 SEM images of fracture surface of Al/Si composites From Fig.3, it is clear that the fracture of silicon particles is serious due to its native brittleness. It is very clear that the fracture path of the Al/Si composite is that cracks pass through silicon particles. There are less......
]. It breaks a new path for the forming of ceramic matrix composites. 2 PHYSICAL MEANING AND MAIN CHARACTERS OF THIXOFORMING OF CERAMIC MATRIX COMPOSITES IN PSEUDO-SEMI-SOLID STATE Firstly the high... the samples tend to emerge crack and brittle failure under loads is that the ceramics are brittle materials with many cracks and flaws. At the same time the compression and impact in micro ranges could......
is performed, crack will occur in AZ91D magnesium alloy. With the development of equal channel angular extrusion (ECAE) technology, it causes a good alternative method to prepare semi-solid billets... A, Prangnell P B, Markushev M V. The effect on strain path on the development of deformation structures in severely deformed aluminum alloys processed by EACE [J]. Acta Materialia, 2000, 48: 1115-1130......
act as the obstacles for pinning the cracks or deviating the crack path from its original direction. Meanwhile, the stress-induced microcracking generated by thermal expansion or elastic mismatch would......
fraction of liquid, and block the diffusion path. Because the die-filling process is short, only can the liquid phase distributed on the surface mix. Consequently, the semisolid slurries can maintain... will not be torn during the die-filling. This is the other source of small crack. These two factors deteriorate the quality of the bonding of the interface. 3.3 Micro-indenter investigation The mechanical......
and X32CrMoV33 hot work tool steel. Wear tests were carried out at 750 °C with a sliding speed of 0.025 m/s, under 5 N load for 60 min. A d10 mm alumina ball ran over disk samples along a circular path having... thermal fatigue cracks, decorated with thick oxides were noted once the surface scales were removed (Fig.2(c)). The surface scales were believed to promote crack initiation while the thick oxides......
the path of least resistance to flow and deposit, i.e. a large pore of carbon paper. Thus, the size of the large pores and the number of large pores reduced effectively, leading to a more uniform... reaction on fiber surface or matrix crack, especially on interface of fibers. Pyrocarbon coated carbon paper had less compact internal structure and higher apparent porosity than conventional carbon......
weld, resulting in great brittleness, so that the joint cracked under a relative low stress. But, when a copper interlayer was utilized, a crack-free joint was obtained by electron beam welding... of brittle TiFe2 compound and the narrowing of intermetallics layer were the key reasons for the achievement of the crack-free Ti-15-3/304 fusion welding joint. 3.1.3 Linear distribution of main elements......
the optical microscope to identify the crack propagation path. 2.4 Recognition distance of tag The materials for antenna pattern, bonding time, and aging time at room temperature can change the performance......