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Along with a number of positive technical properties, gypsum binders and products have the following disadvantages: significant fragility, low water resistance, low frost resistance, high creep when moistened [4].
– Volcanic ash of the Zayukovsky field with a maximum grain size of 5 mm was used as a filler and an active mineral additive.
Table 3 shows the studies’ results of composites using volcanic ash with a maximum grain size of 5 mm.
The studies’ results of composites using volcanic ash with a maximum grain size of 1.25 mm are shown in the table 4.
Table 5 shows the studies’ results of composites using volcanic ash with a maximum grain size of 0.14 mm.

Dong et al. [11] investigated the effect of diffusion temperature on the grain morphology of the α-case layer.
The microstructure of the starting stage (Fig. 3a) is characterized by quasi-polyhedral grains (without distinct grain boundaries – difficult to observe) of the original β phase with excluded α phase lamellae.
After HT (OA), the grain boundaries are clearly identifiable and are characterized by varying sizes.
From the curves shown, it is possible to characterize the dependence of the number of cycles to failure Nf on the load amplitude σa using Eq. 2 and Eq. 3.
Based on the experiments performed, the following conclusions can be formulated: i) Quasi-polyhedral grains and lamellae of the a-phase form the microstructure in the starting stage.

The process was carried out in 5.0 litre flasks containing 200 g of sterilized fine grained or coarse black shale ore suspended in 2000 ml Beijerinck's mineral medium (pH 7) without thiosulfate [8].
The number of cells, the concentration of dissolved organic carbon and metals as well as GC/MS analysis of biodegradation products were analyzed.
The concentration of metals released to the aqueous phase depended on the grain size of the ore too and was the highest in the case of fine grained ore (up to 34% of As) although in this case the role of bacteria was negligible except vanadium extraction.

So the Eq.1 can be expressed as bellow, (2) Where, n is sequence number for the sequence cutting points, n=0,1,2,3,……
Influence curve of grinding wheel graininess on surface roughness is shown in Fig.3b).The conclusions can be derived that the small grain diameter is helpful to reduce the surface roughness both in TUAG and in CG and that the surface roughness value in TUAG is smaller than that in CG.
However, in TUAG, the surface roughness is reduced rapidly, but the reduced trend becomes slow when the grain diameter is small enough.
The machined surface roughness value is associated with grinding wheel velocity, workpiece feed speed, grain size and grinding depth.
The results indicated that both in TUAG and in CG the surface roughness is decreased with the increase of grinding wheel velocity and grinding wheel graininess; the surface roughness is increase with the increase of workpiece feed speed and grinding depth; the grain size has the most obvious influence on surface roughness and that the ultrasonic vibration is helpful to decrease the surface roughness.

Today, VC particles are mainly used to refine grains other than becoming reinforcement.
Results and Discussions 3.1 Microstructure 3.1.1 Fracture surface microstructure analysis (a) 40vol.% (b)55vol.% (c) 70vol.% Fig.1 SEM micrographs of fracture with different VC content As shown in Fig.1, the extended patterns of material fracture become smaller with the increase of VC content, it is determined the grain growth is inhibited, so as to the hardness increase with increasing of VC content.
But VC particles also can separate the organization at the grain boundary; the separate is not obvious with 40vol.
Fig.2(c) shows the surface is relatively rough, caused by the loss of large number of particles, and VC content is too much to cause tissue fragmented, the effect of iron-based bonding to the VC is limited, when the material is subjected to friction and impact, a large number of particles of the material fall off, resulting in surface damage and increase the friction coefficient. 3.2 XRD analyses (a) 40vol.% (b)55vol.% (c) 70vol.% Fig.3 XRD pattern of VC/Fe Composites metal materials Fig.3 is XRD patterns of VC/Fe Composites metal material with different VC content.
This is believed to be due to the finer grains.

The numerical simulation model that the TNT grains working to the metal plate is set up by ANSYS/LS-DYNA, to study the changes of the reflected pressure and impulse on the different grain qualities and distances.
TNT explosion Air Plate Fig.2 Sketch model Analysis and comparison of the simulation results On the different qualities of TNT grains of columnar charges, the aspect ratio is 1:1, and the TNT grains blast on the square plate of the same size.
It is caused by the reason that the boundary of plate can no be clamped absolutely in the experiment.The tensile strain of the plate clamped boundary increases the deflection of the plate, thus the auxiliary value φ is brought forwards, which is the ratio of the experiment deflection to the simulation one, and φ is bigger as the number of the broken screws increasing.
Based on Eq 3 and large numbers of simulations, the parameters of these levels are obtained, as showed in Table 2, and the P-I diagram of metal is showed as Fig 4.

Initial parameters for the dynamic model are geometry of the spiral itself, some physical and kinematic parameters - vibration frequency and number of revolutions.
For screening grains of definite fraction into the lower product the static clearance (clearance between the turns of spiral in its still condition) – zст must be less than upper border of this fraction, and the grains with its average size more than zст go down during the spiral vibration.
That is, there is the “opening” of turns up to some definite size, we will call it dynamic clearance – zд, where hard grain go.
Let’s suppose that section DF (closest to bedding -in or clearance bearing) approximately equals to zст,, and section AB (middle clearance) approximately equals zд, all the rest clearances between them increase in arithmetical progression, that is with some increment , determined by the formula: (3) where i/4 – is the integer number of the spiral clearances on the arch length (or H0/4).
Naturally, at dз=z the particle cannot go through the hole, consequently the hole size must be increased relative to the grain size (here we can include increasing the screening surface hole size in the result of the screen bending). z = dз/0.8 for the drum screen.

Table1 Experiment schemes, % grain size number 3-1mm 1-0mm <0.088mm magnesite MA magnesite magnesite powder iron scales high iron magnesite 0 35 15 15 35 0 0 1 35 15 15 35 3 0 2 35 15 15 35 6 0 3 35 15 15 35 9 0 A 35 15 15 35 0 3 B 35 15 15 35 0 6 C 35 15 15 35 0 9 Experiments process.All raw materials was mixed, 4% sulphite lipuor was added mixture.
From Fig.4 we can see compression strength is bigger adding iron scales into samples than adding high iron magnesite. because Fe2O3 and MgO react, this reaction can produce low-melt mineral that connect grain and grain.
Table 2 Relationship between addition content and thermal shock resistance number sample 1 2 3 4 5 6 7 8 0# ○ ○ □ □ △ △ × × 1# ○ ○ □ □ ☆ △ × × 2# ○ ○ □ □ ☆ △ × × 3# ○ □ ☆ △ × × × × A# ○ ○ □ □ ☆ △ □ × B# ○ ○ □ □ ☆ △ × × C# ○ ○ □ ☆ △ × × × ○-free crack, □-small crack, ☆-surface grain off, △-big crack, ×-damage over 50%.

This presentation examines a number of recent aerospace applications of Superformed 5083; from contemporary tool designs through to finished components.
Although drop hammer forming can be quite versatile it has a number of “challenges” including environmental issues with noise and the toxicity of the lead based tooling used.
The SPF/QPF grades of the alloy are now commercially produced by a number of suppliers in Europe, USA and Japan.
The’ desensitized’ stable microstructure shows the resulting absence of beta phase at the grain boundaries.
Superform has over the years produced a number of such rib stiffened outer panels.

Based on the Pd film deposition parameters and from TEM bright field images (Fig. 1a), Pd films show a classic zone-3 morphology characterized by loosely held columnar grains.
Suitable XEC’s (hklS1 and ½hklS2) were calculated using widely applied grain-interaction models: Voigt, Reuss, and Hill’s weighted average, from single-crystal elastic constants of Pd and PdH0.6 at 300 K [11].
For a Pd film clamped onto a substrate, only in-plane grain interactions are expected, as compressive forces due to the hydrogenation results in a biaxial state of stress exerted by the substrate.
Hence, the (de)-hydrogenation stresses in these Pd films were estimated by using Hill’s weighted average grain-interaction model, which is the arithmetic average of x-ray and macroscopic elastic constants as calculated with the Reuss and the Voigt grain-interaction model.
Residual stress vs number of deloading cycles.