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Limited experimental work also suggested the complicated material and mechanical property of the fusion zone and the heat affected zone (HAZ) especially in dissimilar weld joints might play an important role in promoting SCC growth.
It will make the results a certain degree of error because the mechanical properties continuity at the interface of materials is ignored.
On the assumption that the mechanical properties at the dividing lines of each two sections are not continuous, it is almost impossible to investigate the crack at the fusion line.
Table 1 shows the material mechanical properties of three zones in the dissimilar weld joint.
Tab.1 Material mechanical property in the dissimilar weld joint.

Major microstructural factors controlling properties of magnesium alloys after semisolid processing are considered.
The assessment is not straightforward since some factors may superimpose on each other.
For example, while comparing mechanical properties it is difficult to separate the contribution of porosity and other defects in casting from the pure microstructure factor.
An example of matrix used for assessing properties after semisolid processing Casting Semisolid Wrought Structural feature Dendrites Globules/dendrites Grains Integrity (porosity-P) Pc Pssp< Pc 0 Alloy properties Low Intermediate High Component properties Low Intermediate High Heat treatment No/Yes Yes/No Yes Process temperature Above liquidus Liquidus-solidus Below solidus Component cost Low Intermediate High Role of Microstructural Components For a given chemical composition of a magnesium alloy, the technique of component manufacture affects the microstructural factors, which control properties.
Since the particle size affects the slurry flow mode and properties of the final component, its control is of engineering importance.

The Influence of Processing Parameters on Mechanical Properties and Microstructure of Welding Zone for Ti3Al-TC4 Dual Alloy Zekun YAO 1,a, Xinmin LIANG 1b，Hongzhen GUO 1,c, Wangbin 1, Guohui LI1 , Zhiqing QIAO 1 Hui ZHANG 1 1 Northwestern Polytechnic University，Xi'an, China a yzekun@nwpu.edu.cn, bchm96@sohu.com, czhguo@nwpu.edu.cn Key words: dual alloy processing parameter variance analysis microstructure Abstract It has been investigated that the influence of processing parameters on mechanical properties of weld zone for Ti-24Al-15Nb-1.5Mo and TC4 dual alloy welded by electron beam in vacuum.
The results shows the remarkable influence factors are heat treatment regime and deformation for yield strength of welded dual alloy samples at room temperature tensile test, and the remarkable influence factor is forging temperature for the elongation in tensile test at 500ºC.
The microstructure and mechanical properties of this alloy are affected by processing conditions.
The objectives of this investigation are to examine the influence of processing parameters on microstructure and mechanical properties of the welded Ti-24Al-15Nb-1.5Mo/TC4 dual alloy through near isothermal forging, and to research the practicability of processing this sort dual alloy.
A L8 (2 7 ) orthogonal experiment table of four factors and two levels had been designed.

METALLURGICAL AFFECTS OF THREE DIMENSIONAL PRINTING BASED RAPID CASTING SOLUTION Rupinder Singh1, a 1Department of Production Engineering, GNDEC, Ludhiana, India aemail: rupindersingh78@yahoo.com Keywords: Three dimensional printing; rapid castings; mechanical properties; micro structure.
Abstract: Three dimensional printing (3DP) as rapid casting (RC) solutions has transformed over centuries from black art to science, but the metallurgical impinge on the process responsible for change in mechanical properties (like: surface finish, hardness, dimensional stability etc.) are still disputed.
The result of study suggests that prominent reason found to be responsible for improving the mechanical properties of RC is control of heat transfer rate while solidification (thus reducing dendrite formation).
The comparison among different alloys/metals w.r.t dimensional tolerance, mechanical properties may be studied and mathematical model for specific volume, pouring temperature and the shell thickness may be developed.
Also the effect of different powder materials used for making shells may be studied for dimensional accuracy and other mechanical properties.

In this process, factors such as current density, temperature, electrolyte concentration and additives can significantly affect the performance of the electrolytic copper foil [4-5].
Current density, which is an important parameter for metal electrodeposition, affects the surface quality and mechanical properties of electrodeposited metals.
However, most of the current research on current density is not systematic, and there are few comprehensive studies on how current density affects the surface, internal structure and mechanical properties of copper foils.
This paper aims to explore how current density affects the surface morphology, microstructure and mechanical properties of electrolytic copper foil systematically.
Research on Tensile Properties The mechanical properties of the electrolytic copper foil at different current densities are shown in Fig. 5.

Cross-linking density and mechanical properties of the composites were also studied.
Moreover, different amount of magnetoactive fillers influence mechanical and magnetic properties of the vulcanizates.
The configuration and rigidity of the chain structures depend on several factors including the strength and distribution of the applied magnetic field [4].
There are numerous factors which can affect the manner in which an MRE will behave, for example, the elastomer matrix will have its own material properties of elastic modulus, density, etc.
Results and discussion Mechanical properties Table 1.

Influencing factors on slope stability Engineering geological conditions.
So that sliding force of the slope increased, the anti-sliding force reduced, safety factor was lower.
The occurrence of landslide throughout the process was mainly infected and controlled by slope structure, lithology, rainfall and other factors.
Table 1 Physical and mechanical properties of initial soils and rock index soil E[GPa] n g[KN·m-3] Shear strength [°] C[KPa] Gravel soil limestone mudstone Mudstone intercalated with coal Fracture 2.0 12.0 8.0 7.0 0.4 0.40 0.24 0.25 0.30 0.35 16.1 34 26 24 18.2 37.4 56 42 34 31.5 47 320 240 210 29 Table 2 Physical and mechanical properties of different saturated soils index soil E[GPa] n g[KN·m-3] Shear strength [°] C[KPa] 11.2% Gravel soil Fracture 2.0 0.4 0.40 0.35 16.1 18.2 37.4 31.5 47 29 35% Gravel soil Fracture 1.7 0.36 0.40 0.35 16.4 18.5 36.0 29.0 46.5 27.5 70% Gravel soil Fracture 1.3 0.3 0.40 0.35 16.8 18.7 33.8 27.6 45.8 26.8 100% Gravel soil Fracture 1.0 0.2 0.40 0.35 17 19 32 27 45 26 Fig.2 The engineering geological profile Fig.3 The FEM grid model of slope The results and analysis.
This model considered only the role of rain on the soil shear strength reduction, it was necessary to go further analysis on other factors that influenced and affected on the sliding body.

Factors that Affect Fibrillation of the Liquid Crystalline Polymer (LCP) Phase In an Injection Moulded Polycarbonate / LCP Blend L.P.
Since the LCP fibres have high orientation and high strength, enhancement of mechanical properties of the molded product is attained.
Injection moulded LCP blends usually have low mechanical properties due to the thick samples resulting in low shear stress experienced by the LCP phase [10,11].
However, due to the popularity of this processing method, it would be very useful to be able to develop LCP blends with good mechanical properties through this method.
By having a highly fibrillated morphology, a better enhancement in the mechanical properties is expected.

Microstructure and Toughness Properties of Subcritically, Intercritically and Supercritically Heat Affected Zones in X80 Pipeline Steel Sadegh Moeinifar School of Engineering, Islamic Azad University, Shoushtar Branch, Iran moeinifar@gmail.com Keywords: Microalloyed steel, Welding Simulation, Heat affected zone, Microstructure, Microhardness, Charpy.
The objective of this paper is to study the influence of second peak temperature during simulated welding on properties of the subcritically (S), intercritically (IC) and supercritically (SC) reheated coarse grained heat affected (CGHAZ) zones.
Fracture toughness property is a major factor on the design of oil and gas pipelines.
In setting specification requirements for future construction of new pipelines it is important to have a good understanding of the local brittle zone (LBZ) properties after welding.
The austenite grain size could not be the controlling factor of the HAZ toughness [4].

In the field of welding, the welding thermal cycle generates inhomogeneous heating and cooling, resulting in inhomogeneous microstructure and mechanical properties in the weld joints.
HAZ is so narrow (about 2-3mm) that it is hard to determine mechanical properties on microscale by use of traditional methods.
The variation in microstructure is compared with the changes in micro mechanical properties.
Fig.5 Micro mechanical properties of weld joints Fig.5 SEM image of nanoindentation (a) CGHAZ (b)FGHAZ The relationship of micro mechanical properties and microstructure Nanoindentation hardness variation has a strong relationship with microstructure.
Cementite precipitates and high dislocation density in CGHAZ and FGHAZ are two key factors to strengthen the microstructure with the principle of precipitation hardening and dislocations strengthening, which increased the value of nanohardness.