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+ MgZn2+CuMnZn). And Cu accelerated the separation and spheroidization of non-dendritic particles during isothermal heat treatment, and the effect is optimal when the Cu content (mass fraction) is 1.0.... During the whole isothermal heat treatment process, the semi-solid microstructure evolution mainly experiences four stages: initial coarsening, tissue separation, spheroidization and final coarsening......
. The results show that after deep cryogenic treatment, WC grains are refined into triangular prism with sound edges via the process of spheroidization, but WC grain size has no evident change... into their most stable state via the spheroidization. The martensite phase transformation in the cobalt binder is also observed during the DCT, and the mechanical properties of cemented carbides can......
and time can augment the volume fraction of liquid phase and accelerate the grain spheroidization, as a result of which the requirement of semi-solid forming can be satisfied. Due to the higher aberration... is about 68%. Key words:wrought aluminum alloy; hot extrusion; reheating; mechanism of micro structual evolution; spheroidization; volume fraction of solid phase; [全文内容正在添加中] ......
and growth behavior of the resulting grains, structural separation and spheroidization of primary particles, and the final coarsening behavior of the particles. Compared with the alloy without ball milling... they are heated for 30 min (Fig. 4(i)). Therefore, it can be suggested that the structural separation and spheroidization of primary particles are the main phenomena occurring from 5 min to 30 min. However......
mechanism and spheroidization microstructures, the alloy tested at room temperature(RT) exhibits higher 0.2% proof stress(YS) of 206 MPa, ultimate tensile strength(UTS) of 331 MPa and elongation of 10......
microstructure changed from petal-like one (60-80 μm) to spherical one (≤15 μm). When the mass fraction of Ca reaches 0.05%, spherical I-phase with the largest quantity, highest spheroidization rate and highest..., highest spheroidization rate and highest circular degree can be obtained. Further increasing in the addition of Ca, the morphology of I-phase changes from spherical to petal-like, and the quantity......
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that the mechanisms of morphology transformation are the same to the spheroidization mechanisms of lamellar structure. Boundary splitting and termination migration are more important than coarsening due... resistance can be improved. This is commonly referred to globularization or spheroidization. Globularization of lamellar structure occurs during primary working, in which ingots are transformed to semi......
the partial remelting, with prolonging the holding time and increasing the remelting temperatures, the solid grain size increased. With the increase of remelting temperature, the degree of spheroidization... as liquid phase has occurred at grain boundaries, grain spheroidization and coarsening were activated simultaneously (Fig. 4(a)). When the holding time was extended to 20 min, an examination......
of Cr filaments at elevated-temperature is as follows: cavitation, longitudinal splitting plus, cylinderization plus, breakup to complete spheroidization failure. The simulating result shows... of the diffusional spheroidization of rods[J]. J Appl Phys, 1995, 77(11): 5647?5654. [19] SHARMA G, RAMANUJAN R V, TIWARI G P. Instability mechanisms in lamellar microstructures[J]. Acta Materialia, 2000......
