Search results

For predictive purposes, a number of methodologies has been developed, which allows to quantitatively describe the influence of flaws which possess the ability to provoke cleavage fracture.
Thereby, the underlying mechanism for the triggering of cleavage fracture is based on the generation of microcracks, which is described by the movement of dislocations in favorably orientated grains and the corresponding formation of uneven distributed stress fields within the grains [7, 8].
In the presence of sufficiently high stress fields, grain boundary carbides may fracture which is believed to be the cause of microcrack generation in the microstructure of mild steels [9].
The σc value can differ greatly, as the microstructure and the grain size play a major role for the estimation of the magnitude of the critical stress value σc [10, 11].
(2) m and σu are the Weibull parameters and σ1 describes the first principal stress. npl represents the number of all in the loading history so far plastified volume elements.

Hot air drying is still the most common method used in the agroindustry for processing and preserving grains and seeds, but its main drawback is the high energy consumption.
The equilibrium moisture content was considered to be zero, since a prolonged exposition of the material to IR radiation causes complete removal of moisture inside the grain.
This number of terms ensured a deviation of only 0.5% for the initial period of drying (Fo = 0).
Cenkowski, Grain Drying.
Prado, Performance evaluation of an infrared heating-assisted fluidized bed dryer for processing bee-pollen grains, Chem.

Such a drop in Cwr, sus, HRC is associated with an increase in the brittleness of the alloy as a result of forming a large number of borides and carboborides of complex composition.
However, if one compares the sizes of dendritic eutectic grains (the light component in Fig. 4), the difference can be noticed at once.
No carbides were found in eutectic cementite; they are found only in austenitic dendrites or dendritic eutectic grains (ledeburite).
Spectra for cementite of large (11.4% Mn) – (a) and small (19.3% Mn) – (b) areas At a high cooling rate of 15.2°C/sec, a big number of large cementite fields are formed, so most of the manganese is concentrated there.
In cementite areas, different concentrations of manganese are also observed, but this is due to the size of the cementite grain, which depends, respectively, on the cooling rate.

Rapeseed oil was provided by Dantu grain and oil chemical plant, China. -10PD was obtained from China Petroleum & Chemical Corporation.
Table 2 Main chemical composition (wt.%) of RME a RME Content RME Content C14:0 0.33 C16:1 0.44 C16:0 9.35 C18:1 40.33 C18:0 3.51 C20:1 3.05 C20:0 0.79 C22:1 6.95 C22:0 0.49 C18:2 25.25 C24:0 0.22 C18:3 7.38 aCm:n is shorthand of fatty acid methyl ester. m is the number of carbon atom in fatty acid group. n is the number of double bond.
RME was mainly composed of long chain fatty acid methyl esters (FAME) of 14-24 even-numbered C atoms.
To organic compounds with similar composition and structure, substance volatility got poor with increasing the molecule mass (the number of carbon) and molecule 3D-structure.
It was chiefly because -10PD was mainly composed of alkane of 8-26 C atoms, and RME was mainly composed of FAME of 14-24 even-numbered C atoms.

By reducing chipping and flank wear, one can reduce the tool costs related to cutting processes and reduce the number of times the insert has to be exchanged, leading to improved productivity.
By reducing chipping and tool wear, one can reduce tool costs related to cutting processes and reduce the number of times the insert is exchanged, thereby improving productivity.
Chou et al. showed that the wear resistance increases monotonically with decreasing cBN grain size [3].
Silicone fluid (KF-96; Shin-Etsu Silicone) was used as the polishing slurry in which 4-20 micrometer diamond or silicon carbide (SiC) grains were used as abrasives.

Large numbers of superplasticizers are absorbed onto the surface of C3A and C4AF.
If there were too much C3A and C4AF, large numbers of superplasticizers would be absorbed.
With reasonable increase in the maximum grain size, total surface area of aggregate decreases, so the workability of fresh concrete can be improved.
The dissolution rate of dehydrate gypsum is higher than that of anhydrite, so large numbers of sulfate ions can be generated during mixing.
One is to make superplasticizers into particles with different grain sizes and dissolution rates.

The AE signal of accumulative counts number and amplitude in time domain exhibited a roughly sigmoid variation including three stages, which reflect approximately the evolution of LTD.
For AE signals detected, the acoustic parameters to study are as follows: (1) Counts number: number of times that one given signal exceeds the threshold within the duration; (2) Amplitude: a peak voltage of one given signal waveform which is expressed on a decibel scale; (3) Duration: time interval between the time of the first and the last exceeding the threshold; (4) Peak frequency:a frequency feature at which peak magnitude is observed in the power spectrum.
As discussed previously [3-5], the tetragonal-monoclinic phase transformation generated from the nucleation of monoclinic phase in the tetragonal grains yields micro- and macro-cracking.
The AE signal of accumulative counts number and amplitude in time domain exhibited a roughly sigmoid variation including three stages, which reflect approximately with the evolution of LTD.

Under the certain experiment condition, with the content of the abrasive 10% and grain size 800# of SiC, best machining effect can be achieved.
When the content of abrasive is low, there are little abrasive particles spreading around in the grinding fluid, so the number and the cutting capability of abrasive particles are limited.
It is mainly because the number and the cutting capability of abrasive are limited when the content of abrasive is low.
As the content of abrasive increases, the number and the cutting capability of the abrasive improve, and the surface of the workpiece becomes smooth.
Under a certain condition, with the further increase of the content of abrasive, the number of the abrasives which participate in the MR-effect grinding fluid reaches to saturation and keeps a balance level.

Shobha2,b 1Assistant Professor, Department of IEM, DSCE, Bangalore, India - 560078 2Assistant Professor, Department of IEM, MSRIT, Bangalore, India-560054 aEmail: vinayashree04@gmail.com, bEmail: shobhamtech@gmail.com Keywords: metal matrix composite, glass fiber, stir casting, hardness, Rockwell Hardness Number (RHN), Ultimate Tensile Strength (UTS) Abstract.
Figure 5 depicts that large amount of inter dendritic Al-Mg2Al3 eutectic (gray) in the matrix of aluminum solid solution with grain boundary clearly defined and inter metallic component being visible.

The Al5Fe2 phase consisted of columnar grains having a {001}-fiber texture.
The lack of bulk material has limited the number of studies on the properties of iron aluminides.
The columnar Al5Fe2 grains possess a pronounced {001} fiber texture (Fig. 3(b),(c)).
This reflects the anisotropic diffusion processes in the [001] direction in the columnar grains in accordance with its anisotropic crystal structure [13].
Additionally, the location of Fe, which remained far behind the maximum growth front of the fringy Al5Fe2 layer in between the columnar Al5Fe2 grains (Fig. 2 and 3), indicates qualitatively that Al is the dominantly mobile species as without DC application [9], albeit it diffuses faster.