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The main characteristics of selected volcanic initial rocks for aggregates and heat-acid-resistant lightweight concretes on their base N Parameters Types of initial rocks for aggregates Types of heat-acid resistant concretes Tuff Pumice Tuffcrete pumice concrete 1 Average density, [kg/m3] 980….1340 393….483 1578 1118 2 Real density,[g/sm3] 2.62….2.65 2.43…2.52 - - 3 Porosity,[%] 49…63 80….84 - - 4 Fire resistance, [℃] 1180…1210 900…950 1200 850…900 5 Softening temperature, [℃] 1100…1120 850…900 1150 780…830 6 Heat resistance, the number of air thermal cycling 40 ... 800 [℃] (40...700 ℃) * >25 >25 20 20* 7 Relative linear thermal deformations at 900 (700 ℃) *,[%] -during first heat treatment - after recurrent heat treatment +0.53…+0.63 +0.48…+0,62 (-0.48…-0.84)* (+0.28…+0.036)* +1.76 +0.38 -3,.52* +0.46* 8 Relative volume deformations,[%], after heating up to temperature: - 800 ℃ (700 ℃) * - 900 ℃ (800 ℃) * +0.015 +0.24 -2.75* -7.2* -0.5 0.34 -2.34
The crushed sands of fractions 0.14 ... 5.00 mm (with a particle size of 2.5...3.0) and crushed stone fractions are used in concrete and macadam with grain sizes from 5 to 20 mm.

Table 2: Physical properties of AZ31 AZ31 physical property Value Thermal conductivity [W/mK] 76.9 Specific heat [J/kgK] 1040 Density[kg/m³] 1780 Poisson’s Ratio 0.35 Young’s Modulus [GPa] 45 Table 3: FE model parameters Parameter Value Tool temperature [°C] 20 Blank temperature [°C] 450 Forming speed [mm/s] 250 Number of elements for blank 3250 Friction coefficient 0.13 Heat transfer coefficient [J/m²sK] 46x103 Results and discussion The results of the uniaxial tensile tests at temperatures between 20°C and 450°C are shown in Fig. 5(a) for a strain rate of 1/s.
This could be due to a very fine initial grain size in the alloy.

Cold rolling is operated for the work hardening, refinement of crystal grain size, highly dimensional accuracy and improvement of surface quality.
Form the above, the manufacturing cost of Aluminum strip become high because of the number of processes.

Theoretical Foundations and Experimental Methods With increasing temperature, the number of vacancies (holes) in the sites of the crystal lattice increases continuously.
M-elements act as inhibitors of grain growth during alloy nanocrystallization [10–11].

Grain size analysis values were used to meet the particle fineness requirements for the following studies.
To determine the number of magnetite compounds in the samples, they were subjected to magnetic separation.

The addition of ATT increases the water absorption rate because ATT is a porous material and contains a large number of hydroxyl groups with relatively hydrophilic groups.
Evaluating distillers grains as bio-fillers for high-density polyethylene[J].

Sample number Laser Power [kW] Speed of the Al wire feed [mm/min] Intensity of the compressed-air flow [litre/min] Clad thickness [mm] 1 2,5 830 - 1,28 2 2 830 - 0,96 3 1 830 - 0,74 4 1 830 10 0,77 5 1 830 20 0,84 6 1 830 30 1,03 Table 1.
The SEM image of the 5th sample shows that the dark grey, small nearly spherical grains contain oxygen and aluminium, so with a great chance alumina.

(8) where is the Avogadro number, is the density, is the average sound velocity, andare transverse and longitudinal elastic wave velocity, respectively [28].
In earlier years, the effective modulus of polycrystalline materials is approximated by taking into account uniform strain [30] or uniform stress [31] exerted on grains, which are put forward by Voigt [30] and Reuss [31], respectively.

The factor regulating to physical and mechanical properties are crystalline phases, crystallisation degree and fine grained size [6].
Sintering process increased the number of crystalline phases present in the sintered glass ceramic bodies.

The abrasive water jet cutting process is influenced by many parameters such as water pressure, abrasive (mass) flow rate, abrasive grain size, stand-off distance, jet traversing speed, nozzle diameter, etc.
Obviously, granite cutting by abrasive water jet is a complicated process influenced by a large number of factors, of which the jet diameter and traversing speed are among those most influential controllable parameters.