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Erosion tests on high strengh refractory castables were carried out using SiC grains at impact angles of 30°,45°,60°,and 90° with the velocity of 5m/s.In order to study the variation in stress and system energy with impact angles during solid particle erosion process,a single particle erosion model was designed by means of three-dimensional explicit dynamic software ANSYS/LS-DYNA according to experiment parameters.
The samples were 100 mm long,100 mm wide and 20 mm thick.The erodent particles were angular silicon carbide grains with mean diameter 780μm and hardness 32-34 GPa.
In the early stage of erosion test no material is removed, with a increasing number of impacts, the cracks begin to grow and intersect, eventually lead to material loss.
While the total energy in any physical system is conserved, the slightly reduction of system total energy is the result of material loss in the erosion process .Although a single particle is difficult to result in material loss,the results in this study show that some elements are failure due to the impact, simply because the number of thease elements is little.

The suitability of the proposed methods for the calculation of Shannon entropy of the surface analyzed was tested, as well as for determining the area and number of pitting defects.
A number of recommendations are given with regard to the analysis of the local corrosive defects using the integral methods.
The authors of the previous works proposed a number of methods for the analysis of the thermo-mechanical fatigue cracks, sliding bands, and multiple defects of nanocoatings [2,3].
Structural and mechanical defects of the material (grain boundaries, dislocations, inclusions) are the locations of the potential nucleation of pitting – i.e. corrosive ulcers.
An increase in H testifies to an increased number of individual damaged sections, which have brightness that differs from the background of the surface.

When steel has carbon content less than 0.87%, there will be more ferrite while carbon content higher than 0.87% results in separate precipitation of cementite at the grain boundaries, which increases hardness but reduces strength.
The nodules outline the boundaries of the original austenite grains.
The aim is to refine the distorted grains resulting from working (rolling, forging, and drawing) and uneven cooling.
Unified Numbering System UNS: The Unified Numbering System (UNS) is an alphanumeric designation system consisting of a letter followed by five numbers and used in North America.
It is, therefore, difficult to say categorically that isa definite number of types or grades of steels.

Its structure was researched and designed, including determination of setting chamber and pipe number, selection of material and the design of cyclones. 1 Introduction Cyclone dust removal is an old dust removal, nearly a hundred years of application history.
(4) In equation.1~4，where S is the length of settlement room, v the rate of Airflow section, t is the time of settlement, H is the height of settlement room, is the velocity of sedimental dust particles, is the diameter of dust particle, is the density of dust particle, is the density of air, k is the resistance coefficient of Reynolds number.
This may result in that the wind speed decreases with increasing settlement room. 2.3 Third-level dust removal structure design First-level and second-level could remove the coarse-grained dust, make the blast volume distribute evenly, and make the single-tube charge much the same.
The number of the tubes could be obtained by the equation.5.
(5) In equation.5, n is the number of the tubes; Q is the entrance’s amount of wind; q is the single-tube’s processing amount of wind. 1.gas-guide tube 2.out casting of the cyclone 3.cascade deflector 4.spiral vane Figure 4 Structure diagram of vertical cyclone 1.gas-guide tube 2.out casting of the cyclone 3.cascade deflector 4.spiral vane Figure 5 The air inlet way of the old-fashioned Multi-tubular Cyclone The basic principle is as following, the dust under the action of centrifugal force is separated from the airflow, then the cyclone falls into the ash bucket along the inner wall under the action of airflow and gravity, the dedusting is completed finally.

Observations of the fracture by SEM reveal that the dynamic fracture surface for Mg-3.3Li alloy mainly appears to be brittle fracture along grain boundaries.
However, for the Mg-14Li alloy, the fracture is mainly of ductile in both areas, and there are number of precipitates distributing on the fracture surface (Fig. 2c、d).

Note that solid propellant grain used in rocket launch vehicle, in general, is a thick-walled hollow cylinder made of viscoelastic materials [1].
The authors’ simulations provide detailed insight into how flow structure, viscoelastic stresses, and viscoelastic work change with increasing Deborah number.
This is particularly true in the case of solid propellant grains.
[6] Chu, Hung-Ta, and Chou, Jung-Hua "Poisson ratio effect on stress behavior of propellant grains under ignition loading", AIAA Journal of Propulsion and Power Volume (27)(3), 2011, pp. 662
Saravana Kumar, Numerical Studies on Viscoelastic Characterization of Solid Propellant Grain, 15th Asia Pacific Vibration Conference, 2-6 June, 2013, ICC Jeju, Korea

However, it has been difficult for uses of the parts that are required in the high fatigue strength and high reliability, because of a large number of casting defects exist in the material.
Therefore, some treatments to reduce the size of casting defects and the number of casting defects have been studied.
And also, reason of this was that the surface crack initiation period became longer by SP treatment because the fine grains prevented the slip of microstructure also.
If based on the above results, fatigue property of Al alloy might be more improved by applying the shot peening to the SL die-casting material. 10 4 105 10 6 10 7 100 150 200 250 Stress amplitude σa , MPa Number of cycles to failure Nf , cycles NP SP HIP non-HIP 10 4 10 5 10 6 10 7 100 150 200 250 Stress amplitude σa , MPa Number of cycles to failure Nf , cycles NP SP SL(slip) (a) Compare the SP with the HIP (b) Compare the SP with the SL Fig. 7 S-N curves Conclusions Rotating bending fatigue tests were carried out on two types of SP-treated AC4CH.
Reasons of this is that normally peening effects by the SP treatment such as compressive residual stress and work hardening effects are not so large in the Al alloy compared with other metal as steel. 4) The fatigue life property is improved by the SP treatment since the fatigue crack propagation rate decrease and the surface crack initiation period will become longer by the SP treatment because the fine grains prevent the slip of microstructure also.

The microstructure of the alloys is not homogenous, and there are large grains along with small grains, indicating that dynamic recrystallization occurred during the extrusion, Fig. 2(a-b).
Yet, since the Mn content in both the alloys is similar (Table 1), the number of Al-Mn particles is not expected to be different and their effect on the alloys’ corrosion behaviour of the alloys is assumed to be the same.
The Mg2Sn particles are larger, however the number of Mg-Al-Zn particles is higher, i.e. there is more pitting sites on the alloy’s surface.
It seems that the mechanism of corrosion initiation was pitting corrosion and it was affected by the number of second phase intermetallics.
In order to improve the alloy’s corrosion resistance, there is a need to develop an alloy with a tendency to form stable oxide layer, while at the same time it will have a minor number of second phase intermetallics.

Although the broadening of the peaks shows small crystal grain size of the particles and the average crystal grain size can be evaluated utilizing the Scherrer equation, it is important to understand that the Scherrer formula referred as the crystallite size, not a particle size.
After 5-6 days of sample preparation, the distribution consists of two fractions: a large number of small magnetic particles with an average diameter of 77.93 nm (98.8%) and a small amount of large aggregates with an average diameter of 405.7 nm (1.2%).
However, in Sample B that was prepared after about 1-2 days, particle size distribution consists of two fractions: a large number of small magnetic particles with average diameter 140.7 nm and a small part number of large aggregates with average diameter 669,7 nm.
Acknowledgment This research received financial support from grant number 178/SP2H/LT/DPRM/2019, by the Department of Ministry of Research, Technology, and Higher Education of Republic Indonesia, through the Institute for Research and Community Services of Lambung Mangkurat University with contract number: 123.5/UN8.2/PP/2019.

Table.1 The stratum sequence and characteristics in Jiwa area geological time mapping units code Main lithology and ore characteristics Ge Sy Ce Gr Fm Mem Cenozoic Quaternary Holocene Qhf swamps deposits: silt and clay Qhesl slope sediments: gravel, silt and clay Qhal alluvial materials: sand, gravel and clay Late Pleistocene Qp3pal fluvial and alluvial materials: sand, gravel , clay and clay layer Middle Pleistocene Qp2gl glacial drift: sand, gravel , clay Neogene Pliocene Epoch Wuyu Gr upper E2WY gray mid-thick multelements calc-conglomerate, gray mid-thick sandstone, feldspathic sandstones, blue-gray medium mud-siltstone lower thick grey–fuchsia conglomerate, fine-feldspars quartz sandstone, thick brick red, thick sandy and muddy stone, with acidic volcano Lava Paleogene Oligocene E3r upper E3r grey-red medium grained feldspars quartz sandstone, thin feldspars quartz sandstone and grey-green muddy siltstone, medium grained sandstone with muddy-conglomerate, siltstone,
malachite middle grey-red medium grained feldspars sandstone, thin feldspars sandstone and sandstone- silicalites lower thin sallow-grey-red feldspars debris sandstone, thick gravel-sandstone, fuchsia socialites and mudstones Eocene Linzizong Gr E2p upper E2p fuchsia-grey volcano breccia, rhyolite crystal-debris tuffeceous rocks with silicalite lower fuchsia-grey gravel tuffeceous rocks, tuffeceous rocks with dacite crystal-debris glass-debris Paleozoic Carboniferous-Permian Middle Permian P2x P2x thin-mid flint mass, flint belt limestone, mega-thick calsilutites, carbonate deposits,etc, overflowing with organisms as fossils and flint belt early Permian P1a P1a black shale, mudstones (slate), thin siltstone, grained feldspars quartz sandstone or mudstones interbedded with sandstones, limestone lenses with organisms as fossils late Carboniferous -early Permian C2Pl C2P1l gravel-siltstone, muddy siltstone, gravel-multsandstone, feldspars quartz sandstone, etc.
Early- Carboniferous J1y C1y black shale (slate), mudstones (slate), siltstone, thin grained feldspars quartz sandstone, thin grained quartz sandstone and limestone lenses with organisms as fossils, mudstones and limestone with horizontal bedding and insects-holes, Regional Geological Structure Conditions.
According to the research result of geochemical exploration, we knew that 13 kinds of elements is Normal distributions, and As, Sb in stream sediments is great concentration based on analysis of these raw numbers and exclude maximum, compare with the earth's crust abundance, the concentration coefficient is beyond 3; Pb, Cd, W, Sn, Bi and A in stream sediments is concentration elements, the concentration coefficient is between 1-3; Zn, Mo and Au is between 0.5-1; Cu and Hg is less than 0.5.