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The grain growth behavior and mechanical properties in the friction stir weld zone after post weld heat treatment (PWHT) have been investigated.
In order to improve the mechanical properties of softened region, the post weld heat treatment (PWHT) should be followed.
It is reported that during the PWHT, some fine grains in the SZ of Al alloy have an advantage of grain growth and resultantly grow abnormally consuming surrounding grains in spite of the existence of the grain boundary pinning particles [3-4] therefore, the grains structure instability occurred during PWHT and it is important to know the behaviour of grain growth and the effects of the microstructural factors on the mechanical properties of the joints with various FSW and PWHT conditions.
Studies about the behaviours of the grain structure and mechanical properties with various FSW parameters after different PWHT temperatures are still limited.
The heat affected zone (HAZ, b) is characterized by a similar grain structure to that of the BM, however grains were slightly coarsened.

The choice of solvent, control of base volume, feeding methods and other factors were optimized , toluene/isopropanol (85/15) is the best solvent .
Using FT-IR, elemental analysis, TG, DMA, X-ray and other means, we compared the structure, degree of substitution, the crystallinity, thermal stability, dynamic mechanical properties, dielectric properties and acid and alkali resistance between the CECs by solvent method and traditional method.
The degree of substitution (DS) is usually considered to be one of the most important factors in affecting the properties of CEC[2].
Elemental analyses were performed using Element Vario Micro Cube (Germany), degree of substitution and nitrogen content can be measured by elemental analysis as following equation[19]: Dielectric properties were tested by Agilent 4294A impedance analyzer, 0.5cm × 0.5cm small square thin CEC films coated with conductive silver paste adhesive on both surfaces were made as samples, samples’ dielectric properties can be evalued by the value of dielectric constant ε .
Dynamic mechanical thermal performance were analysised by TA U.S. companies DMA2980 dynamic mechanical thermal analyzer .Membrane material samples sized 30 × 6 × 1mm, test temperature -100 oC -200 oC, test frequency 1 Hz, amplitude of 10 μ, heating rate 5 oC / min.

The experimental measurements of the joint properties were also thoroughly presented in [7].
The mechanical and physical properties of the base superalloys Inconel 718 and Mar-M247 are summarized in Table 1 [7].
The properties of WL was presented in Table 1.
Concentration factors in the welded zone of IN718 side.
Nathal, The Mechanical Properties of Candidate Superalloys for a Hybrid Turbine Disk, NASA/TM—2013-217901

It has been ascertained that the flexible electronic form factor affects the quality of the physical and electrical properties of printed pattern and the device performance.
Mechanical flexibility is the key factor towards successful application.
The corresponding mechanical and electrical properties of the printed patterns were further investigated.
Parameter Unit Value Jetting Voltage V 20.00 Nozzle Height mm 0.80 Drop Spacing mm 10.00 - 20.00 Substrate temperature ̊C 40.00 Ink properties such as viscosity, pH, particle size and surface tension are critical factors to be considered to minimize variation in inkjet performance.
The inks were printed in 3 different layers and their mechanical and electrical properties were investigated by bending tests.

Environmental factors in the atmosphere - humidity, temperature, rainfall, high concentrations of various aggressive and non-aggressive substances in the air, sunshine have negative affect on the service life of structures, machines and other equipment which are located not only in the external environment.
And therefore there is a possibility of measurement of environmental factors or study in detail their effect which increase aggressiveness of the environment addressed.
One of the most important factors affecting corrosion processes is the position and location of the surface within the structure.
Reactions also depend on properties of the metal itself.
References [1] Černý, M., Corrosion properties of metal structural materials, SNTL Praha, 1984.

Obtaining new materials with high-quality structural properties is possible using traditional methods [9, 10].
In turn, the form factor in modelling is determined by the random value of these angles, which reflect the individual structural properties of an inhomogeneous medium.
Huliieva, Prediction of the structural properties of powder materials by 3D modeling methods, Materials Science Forum 1068 (2022) 231-238
Kovalenko, Determination of the influence of deflections in the thickness of a composite material on its physical and mechanical properties with a local damage to its wholeness, Eastern-European Journal of Enterprise Technologies, 4, 1(100) (2019) 6-13
Ruban, Investigation of the properties of powder materials using computer modeling, Materials Science Forum 1038 (2021) 33-39

The reason for that is Si3N4 ceramics are characterized by excellent material properties such as high mechanical strength, high temperature resistant and high shock resistant.
One major advantage of the EDM process is that there is no direct contact between the tool electrode and the work piece electrode and thus the process is independent of mechanical material properties of the electrodes.
Gap voltage seems to be the least significant factor affecting MRR.
The most significant factors affecting the TWR are current, servo, open voltage and the interaction between current and servo as shown by the Pareto plot in Figure 3 (b).
Current, servo and the interaction between them were found to be the most significant factors affecting both the MRR and TWR followed by open voltage.

Pongsathorn Kongkeaw et al fabricated bamboo-epoxy composites and tested for its mechanical properties.
It was reported that the tensile strength of the bamboo-epoxy composite material increases with increase in the fiber length without affecting the elongation at break of the composite [5].
Rajesh Ghosh et al fabricated Banana fiber reinforced Vinyl Ester resin composites and was tested for its mechanical properties.
These three factors were set at two levels.
These factors are called control factors.

The study concluded that fiber type, source and structure are the main factors that affect its properties.
The effect of reinforcement weight fraction on the mechanical properties of the composite was investigated.
“Effect of Alkali Treatment on Mechanical Properties of Sisal-Reinforced Polymer Matrix Composite”, International Journal of Mechanical Engineering, 3, 4(2014)
“Fabrication and evaluation of mechanical properties of alkaline treated sisal/hemp fiber reinforced hybrid composite,” Mater.
“Surface modification of sisal fibers: Effects on the mechanical and thermal properties of their epoxy composites,” Polym.

Alginate nanoparticles are obtained by diverse methodologies and the physical and chemical properties can be affected by production techniques and the molecules incorporated.
The structural characteristics of alginate i.e., a ratio of M and G, sequence, G-block length, and molecular weight, are critical factors affecting the physical properties and also the formation of hydrogel and when alginate molecules have longer length of G-block and higher molecular weight, the gels present enhanced mechanical properties [3-4].
The wound healing develops by an interaction among cellular growth factors, blood components and extracellular matrix and thus cytokines are key proteins to promote the healing processes [12].
To import specific effects on the mechanical properties and bioactivities, the diverse molecules can be incorporated into the materials.
Mooney, Alginate: properties and biomedical applications, Prog.