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Large chromium rich M23C6 carbides pin laths and subgrain boundaries and increase substructural strengthening, while dispersion of vanadium MX nitrides contributes to the precipitation strengthening of grains and subgrains.
First, the prior austenite grains in the base material of FB2 steel were significantly larger than in the base material of F steel.
Third, HAZ FB2 and HAZ F revealed the same features; ferritic laths with a dense dislocation net were observed in a coarse prior austenite grain HAZ (CG HAZ), and ‘more or less’ polygonal grains/subgrains with a low dislocation density prevailed in a fine prior austenite grain HAZ (FG HAZ).
The number of carbides measuring up to about 320 nm increased with the time of the creep tests, and coarse Laves phase particles appeared.
The size distribution of precipitates (number of particles vs equivalent diameter in nanometres) in carbon extraction replicas prepared from FG HAZ of steel F: a) virgin specimen, b) specimen C1, c) specimen C2 and d) specimen A1.

The boride precipitations exhibit diverse morphologies, with the in-situ formed TiB phase appearing as either fine needles or coarse laths, predominantly located within larger Ti matrix grains or along grain boundaries.
With an increase in the TiB2 addition phase content from 5 wt.% to 10 wt.%, there is a notable increase in both microstructural heterogeneity and the number of pores.
Additionally, the significant number of crystal defects resulting from the dehydrogenation process began to facilitate element diffusion and pore healing.
The growth of β grains during sintering is pinned and suppressed by the TiB phases distributed within the grains and at the grain boundaries.
Evenly distributed fine precipitates of the TiB phase serve as inhibitors to prevent excessive β grain growth during sintering, while gradual cooling in the furnace leads to the development of thick, nearly equiaxed α crystals within the refined β grains.

A huge number of different process types are in use to produce magnesium-based composites.
When produced using melting processes, nanoparticle-reinforced magnesium composites are expected to improve in strength, due to the grain refinement described in the Hall-Petch relation.
When the materials are prepared by a metallurgical melting process, an additional strengthening by the grain refining induced by the nanoparticles may be achieved.
Due to the non-turbulent flow and solidification under pressure, the castings are free of pores and blowholes, show no shrinkage porosity and have a fine-grained microstructure.

Introduction The Hetao region is an important grain production base of Inner Mongolia, China.
However, large-scale mulching with new film every year come into being of a large number of film residue, leading to the "white pollution", which make agricultural ecological environment degenerated [4].In recent years, although the new biodegradable covers materials have been invented, it have not been applied and extended in agricultural production because of its high cost and poor effect [5].
Re-used film could also increase grain yield of sunflower and WUE.
Grain yield of re-used film was higher significantly 11.4%(in 2010) and 16.8% (in 2011) respectively than that of bare field, grain WUE of re-used film are 9.5 mm-1·ha-1 (in 2010) and 9.8 mm-1·ha-1 (in 2011)respectively, higher significantly 15.7% and 22.7% respectively than that of bare field, at the same time, lower 2.9% and 2.1% respectively than that of new plastic film, but the difference was not significant (p<0.05).
Meanwhile, the grain yield of re-used film was increased significantly, and WUE of re-used film was also increased significantly, no significant with new film.

The microstructure consists of fine Al crystal grains (grain size; around 200-500nm), and inter-metallic compounds.
Alloy powder consisting of Al17 Si2 Fe1.5 Ni1.5 and Misch Metal 5 (numbers are mass %) prepared by an air atomizing process was formed into a green compact with diameter of 85 mm, height of 50 mm and relative density of 80%.
Please be more specific.] was performed on a half-sized rigid-plastic model, with the number of elements between 1030 and 1050.

Introduction Textile reinforced concrete, short for TRC, consists of textile and fine grained concrete.
The elastic modulus of the composite material is a little higher than that of fine grained concrete.
Because neither fine grained concrete nor textiles has the ability of plastic deformation.
(2) Where, E1- the elastic modulus of the composite in stage ; Ef，Ec- the elastic modulus of strands and fine grained concrete; Vf，Vc- the area ratio of strands and fine grained concrete.
And the cracking space is δ, the number of strands is n.

Based on XRD analysis, the powder was examined for its morphology and grain size using a field emission scanning electron microscopy (Model JEOL JSM-7600F, FEI Co., Japan).
At 600℃{TTP}8451 small peaks of Mg5Ta4O15 phase are found firstly, which can be matched with JCPDS file numbers 20-0691 and with increasing the calcination temperature to 700℃{TTP}8451 , the peaks of Mg5Ta4O15 phase observed are becoming sharper, revealing that the Mg5Ta4O15 powder is gradually transformed to a crystalline state.
However, at 700℃{TTP}8451 small peaks of Mg4Ta2O9 phase are found, which can be matched with JCPDS file numbers 38-1458 and become stronger as increasing the calcination temperature to 800℃{TTP}8451 .The Mg5Ta4O15 phase is transformed to the Mg4Ta2O9 phase.
It is clearly seen that the particles calcined at 800 ℃{TTP}8451 for 2 h show uniform grains with an average size of around 40±10 nm.
It indicated that the smaller and more homogeneous grain sizes could be obtained at shorter holding time (2~4h).

Pei et al. established a grinding force model about the number of meshes, spindle speed, feed rate, vibration amplitude and frequency.
Due to the anisotropy of the material, there are a large number of pores on the surface of the material, which further aggravates the complexity and unevenness of the material.
When the amplitude of ultrasonic-assisted grinding increases, the vibration displacement of a single grain on the surface of the workpiece increases, which increases the grinding area of the grains.
Under the interaction of multiple crystal grains, the number of grindings in the same area increases, which makes the surface quality greatly improved.

Fatigue tests have been conducted with loading ratio R=σmin/σmax=0 (zero to tension) and the number of cycles of censored test (runout) has been fixed at 107 cycles.
Digital Image Correlation was used to measure the evolution of the local strains both after single tensile tests and after different number of cycles for a tension fatigue test conducted at constant stress amplitude.
The full-field residual strain maps corresponding to different applied stress levels and number of cycles are obtained through the use of high-resolution Digital Image Correlation (DIC), [12].
Due to the nature of the duplex microstructure of γ-TiAl, in addition to equiaxed grains, lamellar colonies with different orientations are present.
In particular, inside the monitored area of the sample, lamellar colonies oriented around 45° respect to the loading direction exhibit the higher residual strains compared to the neighboring equiaxed grains.

The crystalline grain size of PC composite coatings is smaller than that of DC composite coatings, and the addition of rare earth into the coatings can make crystalline grains become fine, all kinds of grains in the coatings distribute equably and there are not cracks on the surface and in the sections.
Introduction Abrasion and wear are the common phenomena in industries and the large number of materials and energy are consumed in abrasion and wear.
Although the quantity of Ni3P increases with the temperature increasing furthermore, the growth of crystal and the reverse effect prevail, resulting in the growth of grains and the decrease of internal stress.