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The scale used here is Vickers and the load applied is 5kg.The hardness value for shell moulding is more compared to that of sand casting because of the fine grain structure for shell moulding.
Test: - Vickers hardness test Applied load = 5kg Hardness number = 1.854L/d2 For Sand casting For Shell moulding D =0.299 D=0.293 L = 5 kg L = 5 kg H.
The thickness of the shell mould is small so that the gases can escape easily and in case of sand casting the thickness of shell mould is very large so the gases cannot escape and gets entrapped inside Sand casting Shell moulding Mean = 6790.92 μm2 Mean = 69336.83 μm2 Width = 714.8 μm Width = 2.877 mm Height = 530.6 μm Height = 2.136 mm Resolution = 2080*1544* 24 Resolution = 2080*1544*24 Volume fraction= 1.79% Volume fraction= 1.128 =14.32% =9.0304% Micro structure: The micro structure obtained for sand casting and shell moulding is a dendritic structure and the shell moulding is having relative fine grain structure because of the rapid solidification in shell moulding Fig 4.3: Micro structure

Introduction It is becoming increasingly important to clarify microscopic plastic deformation processes in β-Sn because of the need for strength analysis of Sn-based lead-free solder joints containing few or only one crystal grain [1, 2].
where A is the slip plane area, a1 and a2 are the in-plane translation vectors, and n1 and n2 are real numbers between zero and one.
The results predict that uniaxial tension activates eight nonequivalent groups of slip systems depending on crystal orientation, and imply that plastic deformations are sensitive to their orientations in Sn-based lead-free solder joints containing few or only one crystal grain.

All diffraction peaks in Fig. 1, a and b can be indexed as the hexagonal structure magnesium hydroxide (JCPDS file number 7-239).
The significant peak broadening indicates the Mg(OH)2 has a very small grain size.
The wider diffraction peak , the smaller grain size.

The film consists of a large nunber of grains whose volume is smaller than 0.5 mm3.
All of these grains are arranged in the substrate in a particular way.
Precision measurement The number of groups 1 2 3 4 5 6 7 8 9 10 The measured gas %CH4 0.22 0.50 0.72 1.00 1.20 1.50 1.73 2.00 2.35 2.50 Experimental results %CH4 0.21 0.52 0.75 0.98 1.18 1.54 1.78 1.94 2.32 2.57 Relative deviation /% 4.54 4.00 4.17 2.00 1.67 2.67 2.89 3.00 1.28 2.80 As Table 1 shows, the relative deviation is below 5%, which shows that the sensor has high precision.

Lanthanum magnesium hexaluminate (LaMgAl11O19, LMA) with its high melting point, high-temperature thermal stability, low thermal conductivity and the plate-like hexagonal crystal morphology has been extensively studied as a potential candidate material for a number of applications in industry, military and scientific research [6,7].
Subsequently, ZrO2-LaMgAl11O19 ceramics with different LMA addition(0 wt%, 2 wt% 4 wt%, 6 wt% 8 wt% and 10 wt%) were prepared using 3YSZ (99.5 wt% pure, grain size 1μm, Orient Zirconic Ind Sci & Tech Co., Ltd., China)as raw materials.
The presence of LMA plate-like grains may play an important role in improving the flexural strength, fracture toughness and crack growth resistance effectively.

Because the FWHM of (0004) rocking curve contains only the degree of tilt that the SiC sub-grains have with respect to the substrate normal direction, the FWHM of (11 2 8) rocking curve was also measured.
Although <11 2 8> direction is not parallel with (0001) plane, we can assume the degree of tilt that the SiC sub-grains have with respect to the substrate parallel direction to the some extent with (112 8) rocking curve.
Journal Title and Volume Number (to be inserted by the publisher) 3 expected to be the impurity effect on the step terrace.

The relationship between the static recrystallization activation energy Q rex and t0.5 can be expressed as follows[4], (5) where, is strain and is strain rate; R is gas constant, J /mol, 8.31 J/mol; T is absolute temperature, K; D0 is the original austenite grain size, 183 mm here; ，p，q，s is constant
The Cu peaks in the spectrum come from the copper network. 100nm (d) (c) (b) (a) Fig.4 TEM micrographs at (a)10s,(b)100s,(c)500s, and (d) EDS analysis of the precipitate shown in (c) (indicated by arrow) According to the model of strain induced grain boundary migration, the driving force of recrystallization Frex is given as follows[6], (7) where, μ is the shear modulus (4´104MN/m2 for steel); b is the Burgers vector (2´10-10m), and Δρ is the change in dislocation density.
The pinning force of particles is calculated by the rigid boundary model (RBM)[8], as follows, (9) where, γ is the interfacial energy per unit area of boundary, taken as 0.8 J/m2; f is the volume percentage of precipitates; r is the particles radius, nm. r is estimated according to average diameter and f is given by empirical equation from Ashby[9]as follows, (10) where, Np is the number of particles estimated from the particles distribution in about 1μm2; d is diameter of particle, nm; s is standard deviation of diameter, nm.

It is a nonconventional machining process in which abrasive grains in a high-speed water jet collide with the workpiece and erode it [1].
Compared with traditional and most non-traditional machining technologies, AWJ cutting technology has a number of distinct advantages, such as no thermal distortion, high flexibility, high machining versatility and good surface quality, easy integration with mechanical manipulators, low machining force and minimal burrs [1].
The abrasive material used in experiments was Garnet, with the hardness between 7 and 9 on the Mohs scale and the grain size # 80.

The average grain size (D), and of these samples, on the basis of information in Pt(111) diffraction peak and Sherrer equation (Eq. 1) and Bragg equation (Eq. 2), was work out respectively and shown in Table 2, and could be found that it was to magnify along with rising annealing temperature
(1) (2) Where, D is average grain size, k is constant of Sherrer (0.9), λ is X-ray wavelength (0.15405nm), θ is diffraction angle of Bragg, β is FWHM, d is crystal face spacing, n is natural number.

By comparing the results with standard JCPDS card (PDF ID number 43-1051) of XRD data documents, the sample was a match to VO2 pure phase.
As seen in Fig. 2. scanning electron microscope (SEM) results showed that the grain size distribution of the VO2 microcrystal is in the range from several micrometers to several decade micrometers.
It indicated that the grain morphologies would be the main factor to affect VO2 phase transition parameters.