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One must remember that high temperatures largely influence the mechanical properties of concrete so it is clear that this creates evolution of the fracture energy up to a temperature of 300°C.
These changes severely degrade their mechanical properties, and compromise the resistance to heat transfer and resistance to fire penetration [10].
As can be predicted from the rapid degradation of the mechanical properties, the crack width is markedly increased with the rising temperature.
Concrete Structure, Properties and Materials, Prentice-Hall Inc, New Jersey, 2nd Ed, pp 390, (1993)
Shah, Factors affecting the cementitious materials at high temperatures and medium [0] heating rates, Materials and Structures issue 39:4 (RILEM 288), pp.455-469, (May 2006).

The specific critical depth of cut apI is given and the main influencing factors of burrs are obtained.
The main factors affecting burr formation in milling include the physical mechanical property of work material, shape of end of workpiece, cutting parameters and cutter geometry, etc.
They have many special properties as follows.
So workpiece with burr produced has to be deburred, and time of the deburring work is long and it often becomes one of the factors which reduce machining productivity, and increase the cutting cost of workpiece.
The main factors to affect burr formation in milling are workpiece material, cutter geometry, cutting parameters, and shape of end of workpiece, etc.. 3.

Machining induced tensile residual stress of components made from Duplex Stainless Steel (DSS) is a major factor affecting their functional performance.
The extant literature reveals that residual stress holds a strong influence on these properties.
DSD provide more reliable, cost effective and efficient one step approach for problems involving twelve factors.
The physical properties of these group of steels combine the properties of both ferritic & austenitic grades.
Nachtsheim, “Definitive screening designs with added two-level categorical factors,” J.

So it is necessary to consider the effect of the flame cutting on the static and fatigue properties of Q345.
In this paper, a test about the static characteristics and fatigue properties of Q345 was launched, and the effect of the flame cutting was considered, as the result, the law affected by the flame cutting on the fatigue properties of Q345 was obtained. 1 Introduction Loader boom is a significant load-bearing component for a wheel loader.
Compared to the raw material, the fatigue properties of the material under the heat treatment will change dramatically[4-7].
It is due to that the flame cutting process equals to a special heat treatment, while the heat treatment can change the material microstructure to improve its mechanical properties, which will enhance the fatigue properties controlled by the surface crack initiation mechanism.
It is shown that Q345 material fatigue properties could be changed greatly by the flame cutting process, which will enhance the fatigue limit about 30%; (3) The static and fatigue properties of Q345 material will be effected evidently by the flame cutting process, so it is necessary to take account of this factor in designing and estimating loader boom-life. 5 Acknowledgment The corresponding author of this paper is Xi Lu.

Especially zirconia has become popular due to its excellent mechanical properties [1, 3].
There have been many studies for mechanical properties of zirconia, but a few studies have focused on its translucency.
Porosity is one of the main factors that influenced the translucency of ceramics [4].
Conclusion Within the limitation of this study, it was suggested that the heating time up to the sintering temperature would not affect the optical properties of high translucent zirconia.
Ban, Effect of coloring on mechanical properties of dental zirconia, J.

For example through adding Alloy to structural steel, optimizing composition, special smelting method, galvanizing and other technology can obtain excellent performance such as high strength, good ductility and toughness, low temperature resistance, high temperature resistance, corrosion resistance and wear resistance properties and so on. therefore high strength galvanized steel has become preferred vehicle body material.
Table 1.Chemical composition and mechanical properties of tested materials /MPa /Mpa C Si Mn P S Others 800--950 500 10(%) 0.18 0.5 2.0 0.025 0.015 ≥0.015 Adopting acetone to clean the welding positions before welding, using the self-made clamp fixing workpiece, ensuring smooth workpiece welding, butt weld welding gap is controlled in plate thickness of less than 10%.
Along the perpendicular direction of weld seams to Cut welding parts after welding, polishing workpiece after acid etching, metallographic microscope is used to observe the weld seam and welding quality, a hardness test has done to weld heat affected zone, and mechanical performance analysis has been done to welding specimen.
(a) Weld pool (b)Heat affected zone Fig.1 Joint microstructure(500) (P=1300W,V=0.96m/min,defocus=-0.4mm,gap0.15mm,α=300,Ar) Mechanical properties tests of weld microstructure.
When the welding speed exceeds a certain value, sensitivity of the welding joint crack increases, Welding speed limit is related with laser power, thickness and other factors.

In this paper, based on the mechanism of freeze-thaw process, several factors affecting the freeze resistance of concrete were considered, and a regression model including the interaction of loads and freeze-thaw was established according to experimental data.
In the effective depth of the freeze-thaw, the freeze-thaw damage is serious, and the mechanical performance is degraded severely.
Although that part of concrete actually remains a little of compressive strength, its properties are extremely unstable.
The only fly in the ointment is that Eq. 2 and Eq. 4 are dependent on many factors such as species of cement, mixing proportion of concrete and concrete additives.
Research on the Bond-anchorage Performance of Frost-resistant Concrete and Anti-freezing Property of Prestressed Concrete.

Dynamic mechanical properties of silica fume concrete in a number of strain rate under the conditions of dynamic compression mechanical properties subjected to various strain rates were studied, and gained the stress versus strain curves, details of an experimental investigation using 74 mm-diameter split Hopkinson pressure bar(SHPB) apparatus were presented.
Introduction Silica fume is the fume reclaimed from smoke and gas produced by silica and ferrosilicon smelting, a large number experimental research and practice indicate that: admixing some silica fume to concrete cannot only meliorate the physical dynamic mechanical properties effectively, but also meet some special construction demand. silica fume has been an important admixture Of concrete in the field such as hydro project, marine port project, transportation project, military project, civil engineering and so forth[1-5].Right understanding of material characteristic in different strain rate and dynamic mechanical properties of silica fume concrete may be great significant to the its construction and extending its applied range in civil engineering.
Via orthogonal experiment, the article is considering four factors, namely water to binder ratio(J),silica fume(G), fly ash content(F) and sand ratio(S).
Rising from the last factor at low strain rate to the second factor at high strain rate in the four factors, it can be seen that the silica fume additive have an important effect on concrete impact performance, especially the performance of the high-velocity impact.
Table 2 Range result of each factor affected dynamic compression strength under different pressure impact 0.2Mpa 0.4MPa 0.6Mpa Horizon J G F S J G F S J G F S 1 56.8 60.3 66.5 58 126.1 123.5 138.5 126.7 178.3 166.9 187.3 174.5 2 62.3 58.2 54.8 59.8 133.8 128.3 120.8 127 174.3 175.1 164 171.1 3 60.3 60.83 58 61.5 119.5 127.6 120.1 125.7 168.1 178.7 169.4 175.1 Range 5.5 2.63 11.7 3.5 14.3 4.86 18.34 1.03 10.2 11.8 23.3 4 Chart 4 Effect of factors on dynamic compression strength The 4th chart is the effect of each factor on dynamic compression strength graphics.

In their next paper [11], they investigated the mechanical properties of FDM parts as affected the same set of parameters.
The foregoing literature review indicates that good amount of work has been done to estimate the mechanical properties of FDM parts.
The final equation in terms of actual factors for the build time response variable is as given.
Chandrasekaran, “Investigation of mechanical properties and porosity relationships in FDM fabricated porous structures”, Rapid Prototyping Journal, vol. 12, 2006, pp.100-105
Mahapatra, “Parametric appraisal of mechanical property of FDM processed parts”, Materials and Design, Vol. 31(1), 2010, pp.287-295

There are several factors that affect geopolymerization, including the type and ratios of the starting materials as well as the curing conditions of the initial mixture.
The experimental design involved the variation of three control factors in five levels.
Factors, such as the curing conditions and the composition of the precursor, strongly affect the structure and properties of geopolymers.
Mehrotra, Influence of granulated blast furnace slag on the reaction, structure and properties of fly ash based geopolymer, J.
Nikraz, Properties of fly ash geopolymer concrete designed by Taguchi method, Mater.