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Constitutive equations At the grain level, the plastic strain rate is given by the sum of the shear strain rates from all the active slip systems , (3) where N is the number of slip systems, is the Schmid tensor of the slip system .
Stable multi-junctions can undergo a maximum number of three serial higher-order non-coplanar interaction types during deformation.
Self-consistent polycrystal models: a directional compliance criterion to describe grain interactions.

Since a number of reports about friction stir incremental forming are not so many and most of them are presented by the authors’ group, results about friction stir incremental forming by the authors’ group are introduced in this paper.
Area of occurring dynamic recrystallization and grain refinement by friction stir incremental forming is considerable to be limited to certain depth from the surface.
AZ80 sheet was thicker and the effect of dynamic recrystallization and grain refinement on the improvement of formability was smaller than those of AZ31 ones.
Acknowledgement Researches introduced in this paper are financially supported by JSPS KAKENHI Grant Number 22360309 and 25289261, and Cross-ministerial Strategic Innovation Promotion Program from Japanese government.

It is considered that the interface between powder boundaries cannot be eliminated immediately after establishing contact, and a certain number of micro-voids formed by the particle surface roughness are located on this interface.
Interface source diffusion follows one of the two routes as indicated in Fig. 2(b), addressed respectively as grain boundary diffusion (along the interface) and volume diffusion mechanisms.
Table 2 Sample Information Extracted from Subroutine in Abaqus Displacement Node Number Radius (r) Contact Pressure [MPa] Micro-void Radius [µm] Diffusion Bonding Parameter … 2.00 A 0.00 48478 0.0075 0.85 … 2.00 B 1.47 38737 0.0288 0.42 … 2.00 C 2.09 27433 0.0466 0.07 … Summary In this paper, the concept of interfacial bonding in powder forging was introduced, and a numerical diffusion bonding (DB) model was developed for a new powder forging technique, direct forging (DF).
Johnson, New Method of Obtaining Volume, Grain-Boundary, and Surface Diffusion Coefficients from Sintering Data, J.

Already by mortars preparation stage, the short fibers are uniformly dispersed and mixed with the very fine dry solid cement and aggregates grains, leading to the production of a homogeneous mixture and finally mortar.
Materials The cement type used was CEM IV 32.5 N and fine limestone aggregates were of 4mm maximum grain (sand).
Table 1: Compositions of mixtures composition codes (the number reveals the % fiber volume percentage) constituents M0 M0.25P M0.50P M0.75P M01.0P M1.25P M1.5P M1.75P M2.0P cement IV 32.5N [g] 1500 1500 1500 1500 1500 1500 1500 1500 1500 fine aggregates [g] 500 500 500 500 500 500 500 500 500 PP fibers [g] 0 2.3 4.6 6.8 9.1 11.4 13.7 15.9 18.2 admixture [g] 3 3 3 3 3 3 3 3 3 water [g] 300 300 300 300 300 300 300 300 300 For each composition three molds for rectangular specimens of dimensions 40mmx40mmx120mm were casted.
Li and his collaborators showed that fiber-matrix interface debonding energy could play important role in their toughening mechanism, even though a large number of possible crack mechanisms could arise [7].

However a comparison of the microstructures shown in Fig. 2 shows that as the PWHT time increases, there is an appearance of grain boundary carbides away from the pearlite zones and these carbides coarsen as the PWHT time increases further.
There also exist now a number of reasonably robust correlations between Charpy results and fracture toughness for use in the upper shelf region [11].
This is borne out by the metallographic examination, which showed an increase in the formation of grain boundary carbides and a gradual increase in the size of these carbides as the PWHT time increased.
This could be due to a number of reasons.

A comparison of the concentration profiles and microstructures leads us to the conclusion that spatial gradient of binder appears due to the infiltration of metal melt into the porous matrix formed by the refractory ceramic grains.
On the contrary, all small pores between grains are filled with the binder.
Different bi-metal materials with layer thickness from 1000 down to 4 nm were investigated, number of layers achieved 5000.
Layer thickness 60 nm, number of layers is 300.

Introduction Concrete is the widely used number one structural material in the world.
Concrete with coconut shell as coarse aggregate and grained palm kernel as fine aggregate and compared with conventional cement concrete with stone aggregate and sand and concluded that they are suitable for light weight aggregate concrete [5].
For conventional concrete 4 numbers of 10 mm ∅-HTS bars were used.
[5] Siti Aminah B.T ,Investigate the combination of coconut shell and grained palm kernel to replace aggregate in concrete, National Conference on Postgraduate Research, (2009) (NCON-PGR)

Some natural fibers that have good potency to be developed as sound absorptive material are wood, cork, kenaf, hemp, cane, cardboard, and sheep wool [4], extracted pineapple-leaf fibres [5], Arenga Pinata fibre [6], palm oil male flower [7]and combination of rice husk grain and coconut coir [8].
Moreover, a perforated panel effectively absorbs the sound energy by composing of a large number of individual Helmholtz resonators.
Acknowledgement The authors acknowledge for the financial support from Research and Community Service Center in Andalas University by research grand of Percepatan Guru Besar (PGB) in year of 2018 by contract number 23/UN.16.17/PP.PGB/LPPM/2018.
Al-Atabi, Acoustic absorption of fibro-granular composite with cylindrical grain, Applied Acoustics 126 (2017) 58–67 [9] E.

The average grain size was determined to be approximately 150μm.
The important deformation microstructure feature is typical dynamic recovery structure due to there exists a large number of subgrains.
In addition, there also occurs numerous Mn-containing particles and Al3(Er,Zr) precipitates in grain interior and boundaries.
(3) There exists a large number of subgrains which indicates typical dynamic recovery structure.

The mean MFA in Acacia mangium increases rapidly as a function of the number of the year and after the 7th year-old it varies between 6° and 10°.
Figure 2 shows the plot of FWHM against tree age for the various wood samples from pith, bark and pith-bark regions for grain size about 150.0 µm.