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., University of Bologna, V. le Risorgimento 4, I-40136 Bologna (Italy) 2 DIPTEM, Via all'Opera Pia 15 I-16145 Genova, Italy 3 DIEM, V.le Risorgimento 4, I-40136 Bologna, Italy a lorella.ceschini@unibo.it, biuri.boromei@unibo.it, cgambaro@diptem.unige.it, d alessandro.morri4@unibo.it, egiangiacomo.minak@unibo.it, ffabrizio.tarterini@unibo.it Keywords: Friction Stir Welding, FSW, metal matrix composites, MMCs, microstructure, hardness, tensile test, impact tests, fatigue, mechanical properties Abstract.
One main limitation of these metal matrix composites (MMCs) is their low weldability by conventional fusion processes, since these lead to relevant microstructural modifications in the welds (such as undesirable matrixreinforcement reactions, particle segregation, evolution of occluded gas), which reduce their mechanical properties [1].
Since the material subjected to FSW does not melt during welding, the resultant joints offer advantages over those produced by conventional fusion welding processes, such as fewer weld defects, better retention of mechanical properties, less distortion, and lower residual stresses.
Mechanical characterization.
In this MMC, FSW also reduced the particle shape factor, from 2.1 in the base material to 1.9 in the welded zone.

Therefore, improving the performance of UF membranes, retention properties of small molecules, as well as development of high-performance UF membranes with different process and making the production large-scaled have important practical significance.
It is known that PES UF membranes have excellent chemical resistance, good thermal stability and mechanical properties and broadly manufactured for industrial applications [3, 4].
The PES/SPSF blend UF membrane not only retains the excellent mechanical strength but also improves the hydrophilic of membrane, and expands the using of the PES membrane.
After that, dried PES was added into the mixture and mixed under constant mechanical stirring for 8h.
As shown in Fig.4 and fig.5, the pure water flux increases with the reducing of ratio of PES/SPSF and then decreases, while all of the rejections reach to 99.9%.Hydrophilic and the structure of membrane are important factors of the membrane performance.

The tool wear affects tool life, dimensional accuracy and surface integrity of workpiece.
Although some reseaches have been conducted for the machining of sand molds in recent years, the main attentions were paid to casting properties of resin sand materials.
The workpiece material was resin sand mold material with a binder and curing agent, whose properties are presented in Table 1.
Properties of resin sand mold Particle(order) Resin(%) Curing agent(%) 24h tensile strength(Mpa) 40/70 0.15 0.3 0.614 Table 2.
Conclusions From the results discussed above, the following conclusions are arrived: 1) Hardness is the most important factor affecting tool wear.

Orientation of fibre preforms is an important factor that affects the properties of short natural plant fibre composites.
Literature reports that dynamic sheet forming (DSF), used for paper production, has the potential to be used to form aligned fibre mats which could improve the mechanical performance of NPFCs [1-3].
Analysis of alignment in such fibre mats would be invaluable for estimating composite properties.
Le, A review of recent developments in natural fibre composites and their mechanical performance.
Efendy, Preparation and mechanical properties of novel bio-composite made of dynamically sheet formed discontinuous harakeke and hemp fibre mat reinforced PLA composites for structural applications.

Of course, the fretting properties of Zr-alloy would be examined precisely before the construction of power stations.
As the mechanical condition keeps constant, the contribution of mechanical factor is thought to be constant.
The friction is considerably affected by the surface condition.
From the polarization curve, Zr-alloy has almost the same static and dynamic corrosion properties as SUS304 in Na2SO4 solution. 2.
Hori: Tribological Properties of SUS304 Steel in Seawater, JSMEInt’l, Jour.

Introduction The epoxy resin has excellent mechanical properties, electrical properties, adhesion properties, heat resistance, solvent resistance and it is easy to mold[1].
Silicone-modified epoxy resin can improve the toughness, high temperature resistance and boiling resistance and other properties of the epoxy resin [3,4] .
The paper mainly study on factors of the synthesis reaction, and prepare silicone-modified epoxy resin, which has good hue and balanced epoxy value, molecular weight as well as molecular weight distribution[7].
GPC test of the synthesis product The molecular weight of the polymer is an important factor to affect the performance of polymer materials.
Characterization and properties of new silicone-containing epoxy resin[J].

The index properties of test soil are given in Table 1.
Table 1 Index Properties of Sample Property Values Cohesion () 0 kPa Internal angle of friction () 33.1o Maximum dry unit weight () 16.6 kN/m3 Optimum moisture content () 7.0% Loading frame Dial gauge Specimen Compaction mold with diameter of 4 inches Proving ring Circular rod Fig. 1 Experimental equipment for laboratory bearing tests.
Comparisons between Test Results and Simulations For the bearing capacity of a circular foundation, the shape factors are required in the bearing capacity equation for the strip foundation.
The values of shape factors have been proposed by several investigators [1-3].
The scaling factor is typically applied through the factor .

No blistering was observed in heat affected zone samples for up to 24 hrs charging.
Development of hydrogen-induced cracking (HIC) has adverse effects on mechanical properties and service life of steels.
Simulations of coarse-grained heat affected zone (HAZ) and normalising of transfer bar (950°C, 20 minutes) were carried out using tubular furnace with either quenching or slow cooling, respectively.
Therefore, differences in grain size, volume fraction and types of the phases are considered to be the main factors determining the trend of residual hydrogen content.
Kim, Effect of environmental and metallurgical factors on hydrogen induced cracking of HSLA steels, Corros.

Introduction The Ti-6Al-4V (TC4) α＋β titanium alloy are widely used in aerospace industry due to preserve better mechanical property with highly favorable properties such as a high strength-to-weight ratio, good heat treatment capability, low density, good biocompatibility and resistance to corrosion under high temperature conditions [1-3].
The study on the chip formation mechanism not only help to understand the cutting process, but also is helpful for the correct selection of tool geometry angle, cutting speed, feed rate and other related factors, so as to optimize the cutting process in the real production [6].
After workpiece material and its properties are determined, the cutting parameters have important influence on chip shape.
Tool geometric angle is an important parameter which affects the tool cutting property, the changes of geometric angle can affect the tool life.
(In Chinese) [6] Yujun Cai, Chunzheng Duan, Minjie Wang, et al: Journal of Mechanical Strength, 2009, 31(3): 387-390.

The biggest advantage of fiber reinforced composite is light mass, for example, the golf shaft which made by carbon fiber reinforced composite, and apply carbon fiber cloth tape molding method, is 30%~ 50% lighter than the metal rod one, while its mechanical properties is highly improved compared with metal rods.
Mechanical Properties.
Strength, toughness, elasticity and other mechanical properties factors should be taken into account when we use sport equipment.
The mechanical properties of common materials are shown in Table 1.
Table 1 The mechanical properties of common materials Material Specific strength, Mpa Specific modulus, Mpa Timber 215.6 18620 Carbon steel 176.4 24500 glass fiber/epoxy 607.6 23520 Boron fiber/epoxy 607.6 98000 Aramid fiber/epoxy 842.8 49000 Carbon fiber(HT) /epoxy 1274.0 88200 Carbon fiber(HM) /epoxy 784.0 156800 Types of sports equipment with fiber reinforced composite There are wide variety of sports equipments, Here are several sports equipments which are made by fiber-reinforced composite materials.