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With the increase of the silicon content in tissue, a large number of primary silicon appears in this material.
In the stretching process, the cracks origin from the junction of grain boundaries as well as primary silicon and matrix because the primary silicon is so ragged and brittle that it will split the matrix, and likely to produce segregation causing stress concentration.
This increases the number of the nuclei and then refines the alloy grain[15].
Therefore, the smaller the size of the primary silicon grain size is and the more equal distribution is and the more smooth and evasive the surface is, the weaker dissevering effect is and the high mechanical properties are.
Effects of combined additions of Sr and AlTiB grain refiners in hypoeutectic Al-Si foundry alloys.

In the Goryeo age, large numbers of ironmaking sites came to be concentrated in the Daesowon-myeon area.
Through following academic excavation and surveys, substantial numbers of ironmaking-related artifacts and sites were excavated.
A comparison of grain size in the composition of tuyeres from Baekje and Goryeo Age ironmaking sites has indicated that with the advent of the Goryeo Age, tuyeres began to be made with clay having fine grain size and high refractory content[16].
The material used for coating was clay with high rock grain content, similar in terms of physical properties to the straw-free furnace wall material.
Ferrite grains are surrounded by fayalite slag Fig. 9 Iron lumps from Tappyeongri site in Chungju Fig. 11 Microstructure of the iron arrow excavated from the same site.

Fig.1 Sand Tank Dimensions and Cone Penetration Test Locations The experiment uses air-dry sand, whose grain size and distribution are shown in Figure 2.
The sand grain distributes evenly, and its non-uniform coefficient (cu ) is 1.62, content of sand grain whose particle size is less than 0.075mm is less than 9.0%, almost free of clay.
Before the explosive compaction, cone penetration resistance value (Ps) of the sand body is measured; the displacement of saturated sand and the sand surface subsidence are tested respectively after 30min, 2h and 24h after the explosive compaction; Ps values are measured respectively 1 day, 3 days, and 5 days after treatment, and test holes are numbered J1, J2 and J3, which are distanced 15cm, 30cm, and 45cm respectively away from the charge hole along the radius direction, as is shown in Figure 1.
The experimental study focuses on the charge forms, charge weight and charge depth along the vertical direction of the sand body, and their co-effect on explosive compaction. 6 groups of tests are carried out, numbered T2 ~ T7, and test parameters of each group are listed in Table 1.
Under the blast loads, the area where sand grain structure is completely destroyed recovers over time, so the Ps value increases greatly.

The associated number evolves from un-extruded to (4) fully extruded region.
Each of the maps contains more than 250 grains.
The crystallographic orientation of each grain is determined randomly, and the same volume is applied for each grain.
Above a given threshold, fixed in this simulation to 5, the grain is assumed to be split into two grains of half-length sharing the same crystallographic orientation.
Under plastic strain, grains are oriented along the alpha fiber.

Sieve analysis was used to determine the size distribution of the blast hole cuttings in the laboratory using sieve shaker while grindability was determined using the ball mill, by grinding for certain number of revolutions.
When material breaks easily at the boundaries this means that individual grains are tough [5].
The grain size of blast-hole cuttings collected from two selected quarries were determined using standard method of America Society for Testing and Materials (ASTM) D 2487 and sieve of the following mesh sizes: 850 µm, 600µm, 425µm, 300µm, 212µm, 150µm, and 75µm were used.
(1) Where G = Grindability W1 = Mass at 75µm in kg N1 = Number of revolution (Rev) Determination of Wear Rate.

In the past few decades, a number of investigations have been carried out to investigate the relationships between the properties of Al-ZnMg-Cu alloys and heat treatment, microstructural evolution, and both [22–28].
Comparing Fig.3, E with A demonstrates that, in line with the literature [16], there is an increase in the number of dimples brought on by the reduction in grain size.
These results have been proven in terms of the sample's grain size in fig. (6 and 7).
Segregated elements are easy to form during solid solution processing, and solute atoms at the grain boundary are easy to diffuse to the grain boundary.
Levy, Effect of Heat Treatment on Solute Concentration at Grain Boundaries in 7075 Aluminum Alloy, Metall.

The numbering of the specimens for each condition is done with P + number.
Due to recrystallization and grain growth the microstructure is coarser grained.
The dislocation density in connection with the heat treatment induces a fully recrystallized fine-grained weld seam of austenite.
The rolling force in that case is significant lower compared to the non-treated case and this difference is rising with the number of rolling passes.
The final heat treatment generates a fine grained microstructure in the weld seam and the material recrystallizes over the entire part.

In a LCF, the Manson-Coffin [3, 4] law, showing a relationship between plastic strain range Dep and number of cycles to failure Nf was proposed as follows; DepNfa =C (1) where a and C are material constants.
Bataille et al. [6] reported that more than 80% of LCF life of AISI 316L stainless steel consists of the propagation of short surface cracks, the surface lengths of which are less than ten grains.
However, the number of crack initiation sites was different depending on the degree of the applied cyclic plastic strain range Dep; the larger the cyclic plastic strain range, the greater the number of cracks.
Fig. 8 shows the relationship between maximum stress amplitude and the number of strain cycles.
These findings imply that in the case of large static pre-strain, a decrease in LCF life occurred according to deformation being concentrated on the softest grain resulting in work softening.

A large number of engineering practice indicates that building subsidence can be controlled in 2 ~ 4 cm in general.
Mattress layer materials generally choose the coarse sand, medium sand or gravel size with 8 ~ 20mm grain size.
drilling machine emplacement drilling to designed depth offer material and raise machine move machine Sealing cap Fig.2 The main process of construction Mattress layer material select gravel of 5 ~ 10mm grain size.
The appropriate number of static load test is 0.5% ~ 1.0% of total number of CFG pile, and each individual test of engineering quantity should not less than 3 points.
Low strain detection quantity shall be not less than 10% to the total number of CFG pile.

Only grain boundary diffusion is seen in the case of the C-type profiles, Fig. 11a.
And the deeper branch represents the grain boundary diffusion.
Secondary Ion Mass Spectroscopy in Fine-Grained Materials The above presented SIMS measurements have been performed for coarse-grained materials.
The microstructure of fine-grained metals can be quite heterogeneous [107, 108].
With the sample-detector distance R = 155 mm, these numbers translate to the angular resolution of ∆θ = 6·10−4 or about 300.