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Long-term effects of these factors may change the physical properties of the insulator, which may affect its thermal insulating properties.
Physico-mechanical properties and chemical mineralogical compositions of cements are shown in table 2-4.
Physical and mechanical properties of cement used in specimen Compressive strength compression/bending, [MPa] in 28 days Curing period, [min].
Currently, the most effective and simple way to improve the physical-mechanical properties of cement solutions and concrete is through the use of chemical additives.
When additives are introduced, the technical properties of the concrete mixture, the hardening processes of the concrete itself and its operational properties change substantially.

The chemical composition of welding materials in the formation of a welded joint plays a decisive role-determines the presence of defects and mechanical properties.
Calculation of Melting Factors, Metal Deposit Factors and Losses The main efficiency and stability indicators for the arc welding process are: melting factor, metal deposit factor and losses.
Results and Discussion The resulting values of melting factors, metal deposit factors and losses are presented in Table 1.
Resulting values of melting factors, metal deposit factors and losses.
Concerning welding and technological properties, all electrodes for underwater "wet" welding are acceptable and suitable for underwater welding, but the best properties were recorded for UW-EZ-2 electrodes by BrocoUnderwater. 2.

College of Materials and Metallurgy, Guizhou university, Guizyang 550003,China awaq0623@126.com, bqbliu2@263.net, cshuijie.qin@gmail.com Keywords: Laser technique; 40Cr steel; Laser surface alloying; Rare earth oxide Y2O3 Abstract: To increase the mechanical properties of the metal rollers, Mo and Mo+Y2O3 alloy powders were designed.
Since rare earth elements and its oxides are of excellent physical and chemical properties, such as unique electron shell structure, outstanding chemical activity and bigger ionic radius, they are usually used as the quality modifier for LSA treatment, which are able to achieve functions of deterioration, strengthening and purification as well as improvement of the performance of the metal alloy layer[4,5,6].
(a) (b ) Fig. 1 Morphology of the alloying layer:(a) without Y2O3 and (b) with Y2O3 As shown in Fig.2(a), from the surface to the substrate, the morphology of alloying layer without Y2O3 could be divided as alloying zone, transition zone and heat affected zone after LSA.
Consequently, the microstructure from the surface to the substrate of the alloy layer consists of alloying carbides, retained austenite and metastable ultrafine martensite in the heat affected zone[9]。.
The reason lies in two factors: On one hand, during LSA, rapid heating and solidifying leads to formation of fine grain size, which strengthens alloying layer.

Among many factors that influence the reliability of a flip-chip assembly using NCF interconnections, the most effective parameters are often the coefficient of thermal expansion (CTE), the modulus (E), and the glass transition temperatures (Tg).
Of these factors, the effect of Tg on thermal deformation and device reliability is significant; however, it has not been shown clearly what effect Tg has on the reliability of NCF.
The material properties of a NCF between the chip and a PCB have enormous effects on thermal fatigue.
Of these factors, the effect of Tg on thermal deformation and device reliability is significant; however, it has not been shown clearly what effect Tg has on the reliability of NCF.
This delamination is mainly affected by the shear strain at the edge of the chip.

To understand inhomogeneous deformation mechanism in polycrystalline metals is important matter for structural use materials, because the deformation behavior of each grain governs the mechanical properties such as deformability, ductility, fracture, and so on.
The mechanical test rig with 200N loading capacity is installed on the rotation stage.
We should take shape factor, Sf more than 0.3 at least.
These are affected by grain microstructure.
The partial deformations affected by local grain orientation are clearly observed in εx and εy.

Analysis by Vickers indentation resulted in hardness of 11.2 GPa and fracture toughness of 24.6 MPa.m1/2, showing the feasibility of producing dense WC-Fe3Al composite with high mechanical properties using the SPS technique.
In these composites, the high hardness of WC grains combined with the ductile matrix, usually cobalt (Co), results in excellent combinations of mechanical properties, especially hardness and fracture toughness [1].
Some variables that affect the formation of compounds by mechanical action include time and energy of milling, which depend among others factors on the ball-to-powder mass ratio (BPR), speed and number of balls [11].
Fig. 4a shows the results of mechanical properties of the composite WC-10% Fe3Al, which had Vickers hardness (HV) of 11.3 ± 0.5 GPa and fracture toughness, KIc, of 24.6 ± 5.6 MPa .m1/2.
The composite had high density of 13.697 g/cm3 (98.7% of theoretical density) and mechanical properties (hardness and fracture toughness) similar or higher than the conventional composite WC-10 wt% Co.

There are many factors influence the risk of proximal femur fractures, which could be divided mainly into two groups named the inner factors and the extra factors [2].
Bone is a kind of anisotropic and inhomogeneous material and its properties vary among individuals.
However, it has been demonstrated that the differences between isotropic and orthotropic material properties assignments are small [10] and in order to reduce the difficulty of defining the material properties, proximal femur in this paper was assumed to be homogeneous, isotropic, linear elastic with Young’s modulus 10 GPa and Poisson’s ratio 0.3.
Fardellone, Extraskeletal risk factors for fractures of the proximal femur, Joint Bone Spine 71 (2004) 14–17
Morgan, et al, Comparison of the elastic and yield properties of human femoral trabecular and cortical bone tissue, J.

Possibility of Evaluating a Depth of Defects as a Hole in a Composite Dielectric Sample by the Parameters of Electric Response to Pulse Mechanical Excitation Petr Khorsova*, Anatoly Surzhikovb, Vladimir Surzhikovc and Roman Laasd National Research Tomsk Polytechnic University, 30, Lenina Ave., 634050, Tomsk, Russia *apnh1@tpu.ru, bsurzhikov@tpu.ru, civa1954@mail.ru, dromanlaas@tpu.ru Keywords: mechanoelectrical transfomations, mathematical model, defect, acoustic wave Abstract.
Introduction Designs from composite dielectric materials are used in aviation, space technology, automotive, mining, civil engineering and other areas in conditions of mechanical, thermal and other loads.
Besides, various technological factors in the manufacturing process can lead to product mismatch with project values: composition violation, a cavities formation, hit of various inclusions.
The essence of the phenomenon is that as a result of pulsed mechanical impact on the heterogeneous non-metallic materials occurs a variable electromagnetic field due to acoustic wave impact on dipole moments of double electric layers on the borders of dissimilar materials, as well as on inclusions with piezoelectric properties.
In the aftermath, the response begins to be affected by responses due to reflected acoustic waves from the sample boundaries and hole lateral boundaries.

Therefore, the skidding wheel distance and time are major factors of tyre wear and smoke [4].
In the Archard wear theory, the volume of tyre tread rubber eroded is defined as: V=KeFRHSD (15) where, V is the total volume of wear amount (m3), Ke is the wear dimensionless coefficient “Archard’s abrasion factor”, which depends on the wear conditions, heavy or moderate, and is affected by the material’s properties and its ability to wear.
Table 2 shows the tyre tread rubber properties [33].
All the simulations show the wheel spin-up overshooting, because the same friction force is affecting the wheel.
Daugherty, “A study of the mechanical properties of modern radial aircraft tires”, NASA TM-212415, 2003

Stability of the Jeffcott Rotor with Local Rubbing He LI1,a, Xiaozhe CHEN1,b, Bangchun WEN1,c 1School of Mechanical Engineering and Automation, Northeastern University, Shenyang, China.
Suppose that k is stiffness of rotor shaft, m is mass, c is bearing damping factor, kr is stator radial stiffness, u is eccentric distance, w is angle frequency of rotor , and ignore the effect of gravity, so that the motion differential equation of local rubbing of Jeffcott rotor system are given by (3) Inducing transformation non-dimension: Motion differential equations of local rubbing of Jeffcott rotor system with non-dimension are as follows: (4) In addition, letting , and just taking account for autonomous system, Eq. 4 is transformed into (5) Where ,, ,
In addition to the clearance and the stiffness ratio b, the system damping and friction coefficient are also important factors affecting rotor stability.
Analysis on vibration properties of rotor rubbing.