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a profound effect on the mechanical behavior of materials, in particular, on the yield stress and hardness. The Hall-Petch relationship[17] is a well-known expression relating the variation in yield...; (1) where σy is the yield stress; σ0 is the lattice friction stress required to move individual dislocation; k is a constant and d is the grain size......
; (c) 342 mm/min The stress-elongation curves at various travel speeds and 500 r/min, are shown in Fig.2. The yield strength at a traveling speed of 124 mm/min was nearly constant. Stress... is low. Fig.3 compares the mechanical property for the base metal at various travel speeds and 500 r/min rotational speed. Yield strength ratios for base metal do not differ greatly with travel speed......
. 2.3 Synthesis of 5-bis(naphthalene-1-yl)-1,3,4-oxadiazole (DNOXD) DNOXD was synthesized with a yield of 81.0% according to Ref.[19]. Its melting point was 182-184 ℃. 1H NMR (400 MHz... over silica using a mixed solvent (volume ratio of dichloromethane to petroleum ether was 3:1) as an eluent to obtain an orange yellow power with a yield of 32.6%. 1H NMR (400 MHz, CDCl3, δ): 9.35 (d......
and conventional annealed pure titanium sheet specimens have obvious anisotropy. For cold-rolled CP Ti sheet, the specimen in 45? direction has higher yield strength, tensile strength and larger elongation than the specimens in the other two directions (Fig.3(a)). In case of conventional annealed specimens (Fig.3(b)), the difference in yield strength, tensile strength and elongation is more significant......
on microhardness Grain size is known to have a profound effect on the mechanical behavior of materials, in particular, on the yield stress and hardness. The Hall-Petch relationship [12] is a well-known expression relating the variation in yield stress to the grain size of a material: σy=σ0+kd-1/2  ......
and different strain rates were studied. Figs.1 and 2 present the strain-stress curves at different strain rates at 20 ℃ and 500 ℃, respectively. The yield limit and rheological stress of 20 steel... of carbon constructional quality steels are very sensitive to strain rate and temperature. Yield stress and rheological stress increases with the increase of strain rate and decreases with the increase......
]. In order to extend the applications of magnesium matrix composites, secondary processing has to be well developed. Extrusion can yield a full integrity wrought material because of its combination... speed of 0.5 mm/min. The tensile property data (yield strength, ultimate tensile strength, elastic modulus and elongation) were based on the average of 3-5 tests. 3 Results and discussion 3.1 Particle......
is the elastic modulus, σy is the yield strength, n is the work hardening exponent, and εp is the nonlinear part of the total strain ε, which defines as (2) where εy is the yield strain. Fig. 3..., the yield strength σy is determined according to the following calculation method [24]: (3) where H is the nominal hardness under a given indentation depth h, h* is a characteristic length depending......
and aerospace industries in order to decrease mass[1,2]. However, as a consequence of hexagonal crystal structure, they generally exhibit only lower ductility and yield strength at ambient temperatures... the relationship between mechanical properties and aging temperatures. 3.1.1 Tensile properties From Figs.1(a-c), we can see that ZK60 magnesium alloy variation trend in tensile strength, yield strength......
processes (ICRPs) [5,6]. DCRPs are not used due to extreme high temperature (more than 2273 K (2000 °C)), needed for the reduction’s high yield. For example, the DCRP’s equilibrium thermodynamics yield... and apparatus for multicomponent ores processing; 5) Rejection of a chemical reaction, if it is characterized by the low yield, very high temperature, extreme high or low pressure, and if it can......