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Grain refinement, a method to improve the mechanical property, has been used by the authors [3] on AZ31 hot-rolled sheets and extruded bars.
The tensile mechanical properties were testified to be improved.
In this paper, the texture effect on the mechanical properties of room temperature and the deformation mechanism at elevated temperatures will be reported.
Result and Discussion Flow curves affected by the grain-refining treatment are shown in Fig. 1.
The mechanical behavior can primarily be related to the textures developed in the specimens, rather than the grain size.

Desai[2] and others have done a large number of the contact surface of the direct shear and single shear test in which they studied the main factors of sand -structure interface.
Particle size ranges from 0.5mm to 1mm and the basic physical and mechanical properties are shown in Table 1.The instrument is the semi-mode direct shear apparatus , as shown in Fig.1.
Therefore compactness has effect on the mechanical properties of interaction between structure and sand sample.
Experimental study of the monotonous mechanical properties of interface between soil and the contact surface of structure[J].
Study of micromechanical properties of sand soil based on the direct shear test[J].

The constructional steels of hydraulic support with international advanced level mainly adopt the high-strength welding structural steel with its tensile strength of more than 700~1000MPa.This paper analyzes the chemical compositions features of S890 high-strength low alloy steel for 900MPa grade.The Influence of welding parameters,peak temperature and on the microstructures and mechanical properties of welding HAZ of S890 high-strength low alloy steel were investigated by thermo-simulated tests, The influence of welding heat input on the mechanical behaviors of the welded joint was also investigated.
In this area, primitive microstructure tempers again or partial re-phase transformations and re-cools,but the area involved in the overlap is limited,so the influence on the properties of S890 steel is not obvious.
But the weldability of materials need continued study , optimize welding process, increase comprehensive properties and bearing capacity of welding joint, to meet the high reliability demand in support design.
In order to study how different welding technological parameters affects HAZ of S890 steel, the welding joint structure and mechanical properties, the weldability of S890 steel ,which is the material of the support and its more than 900Mpa ,is studied by using practical and simulation welding methods in this paper. 1 Test Method Raw material used in test is S890 steel for construction machines that has a tensile strength more than 900 MPa,the composition and mechanical properties are listed in table 1 and table 2. specimens are cut from steel plate directly by using electrical discharge wire-cutting.The specimen size is 10 mm×10 mm×55mm.
But the effect on properties of S890 steel is small in most of the cases because the overlap region involved is limited,the change of hardness in table 6 corroborating that.

Fretting fatigue is one of the major factors in the design of hydrogen equipment.
Introduction The effects of hydrogen on the fatigue properties are being extensively studied in order to establish a hydrogen based economy.
The mechanical properties of the materials are shown in Table 2.
Table 2 Mechanical properties and Vickers hardness Material Condition 0.2% proof stress Ultimate tensile strength Elongation Reduction of area Vickers hardness SUS316 Solution heat treatment 236MPa 631MPa 79.4% 85.6% HV152 SUS304 Solution heat treatment 237MPa 771MPa 72.3% 81.2% HV174 Apparatus and testing conditions.
The internal hydrogen affected not only the fatigue limit but, also the fatigue life, whereas the effect of the internal hydrogen on the fatigue life of the SUS316 is not significant.

Similarly, as reported by Ezugwu et al. [3], increasing the cutting speed and feed rate increases the hardness and depth of the affected layer.
The lubricants used in this experiment were synthetic ester and palm oil and their properties were shown in Table 1.
These factors lead to an increased in cutting force which resulted in greater hardening effect.
The combinations of the aforementioned factors lead to the severe deformation underneath the machined surface.
These factors have led to the improvement on surface roughness.

Damping properties of SMA Sergey Kustov1 and Jan Van Humbeeck 2 1Dep.
Several equivalent characteristics of damping are used, depending on the experimental technique employed to measure damping properties.
(2) The inverse quality factor, Q -1, and the specific damping capacity, Ψ , are W W W W Q ∆ =Ψ ∆ = − π2 1 . (3) Equations (2) and (3) indicate that all basic damping characteristics are interrelated through numerical factors: 1 22 − ==Ψ Qπδ
Even in absence of formation of equilibrium phases (limited diffusion, not too high temperatures, typically below 0.3 Tm) structural relaxation affects strongly the damping properties of martensites.
In fact, damping properties of martensites, associated with the motion of linear/planar defects, can be affected strongly also by the diffusion, assisted by these linear/planar defects.

The specimens were exposed to environments with the temperature up to 1000°C and then subjected to physico-mechanical tests.
One of the key factors for the development of repair materials with required parameters is the selection of a suitable aggregate type including grain size which significantly contributes to the workability of fresh mortar and to the final parameters of polymer-cement composite.
This was particularly affected by the modifying conversion of quartz (573°C) – differential content of this component in the aggregate.
Tests for geometrical properties of aggregates - Part 1: Determination of particle size distribution - Sieving method.
Tests for mechanical and physical properties of aggregates - Part 3: Determination of loose bulk density and voids.

FEA of Planetary Pipe Rolling Process for Stainless Steel Jung-Kil Lee1,a , Dong-bum Kim2,b, Jin-gun Park2,c, Hyuk-soo Shin2,d, Won-yeong Kim2,e, In-hwan Lee3,f, Hae-Yong Cho3,g 1 1600 Chungjeollo (307 Gajeon-ri) Byeongcheonam-city Chunhgnam Province, South Korea 2 Graduate School of Precision Mechanical Engineering, Chungbuk Univ., Gaesin-dong, Heungdeok-gu, Cheongju-si, Chungbuk, South Korea 3 Department of Mechanical Engineering, Chungbuk Univ., Gaesin-dong, Heungdeok-gu, Cheongju-si, Chungbuk, South Korea a kil@kut.ac.kr, b kdb@cbnu.ac.kr, c gareagum@hotmail.com, d guardon@nate.com, e kimwy87@naver.com, f anxanx@cbnu.ac.kr, g hycho@cbnu.ac.kr Key words: Stainless steel, Rolling, Planetary rolling mill, Finite element analysis Abstract: Planetary Pipe rolling process for AISI 304 stainless steel has been studied by using finite element method.
Each of the process parameters affects forming result.
Rotating velocity and revolution does not affect compactibility[4] and are excluded in analysis conditions.
Internal property data for AISI 304 stainless steel in DEFORM-3D is used as property of billet. 3.
Friction is a main factor which makes planetary rolling possible.

Recrystallization state seems not only affect the fatigue life, but also the crack initiation pattern and crack initiation life.
Introduction Nickel base directionally-solidified superalloys are widely used in aircraft turbine blade because of their outstanding properties in high temperature and severe operation condition.
However another forgotten factor that does affect recrystallization is free surface, especially in case that the plastic deformation is under certain threshold.
That perfectly explained that free surface is a detrimental factor besides plastic deformation and high temperature treatment.
Directionally Solidified Non-hafnium Superalloy and Its Overload Mechanical Damage, Materials for Mechanical Engineering, Vol.25(2001):4-7 [2] Y.R.Zheng, Z.C.Ruan, S.C.Wang.

Such materials with low adhesive properties include fluoroplastics, which are the most chemically resistant of all currently known plastics.
It is also important to take into account, when choosing the place of installation and the location of the stand on it, such factors as the direction of currents, surge winds, surf, etc. [22].
The samples on the stand were installed in such a way as to ensure the same test conditions, taking into account the influence of external factors affecting fouling (insolation, waves, currents, etc.).
The tested PTFE coating and the WG-Weleforce LS control paint provide reliable protection against corrosion, but the PTFE coating has significantly better antifouling properties. 5.
The effectiveness of the anti-fouling properties of the fluoroplastic coating in the full immersion zone is 4.7 times higher than that of the WG-Weleforce LS paintwork. 6.