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In particular, ion nitrided specimens of relatively less softening condition showed reduction both the depth and number of cracks compared with the other surface conditions.
To improve the service life of the mould, past efforts have been towards the development of die steel grades offering better high temperature strength as well as toughness and towards suppression of grain boundary carbides during heat for die cavities [1, 2].
The parameters effecting on the thermal fatigue test such as heating rate, cooling time, maximum and minimum temperature, and number of cycles were fully computer controlled.
And the IN specimens of relatively less softening condition (500 °C/4 h, 530 °C/8 h) showed reduction both the depth and number of cracks compared with the other conditions.
The nitriding surface significantly reduced the both the number of total thermal crack and the Lm value of the surface with less softening condition.

The process of 3DP was patented in 1994 by Sachs et al. under U.S. patent number 005340656 [1].
Currently only a few final products are produced by RP machines, but the number will increase as metals and other materials become more widely available [17].
It should be noted that in casting while solidification process is going on, there are preferred grain growth direction and grain re-orientation/ redistribution takes place [4, 22].
Fig.5), at 10mm shell wall thickness, mixed grain with uniform distribution have been observed, whereas at other shell wall thickness dendrite structures have been observed.
This may be because of better heat transfer rate conditions, which results into refine grain structure (with no dendrites).

Segregation of components is limited into the powder particles，which can eliminate the macroscopic segregation of conventional casting and has the advantages of uniform microstructure and fine grains，obtaining good yield strength and fatigue properties.
Engine fuel contains a large number of impurities such as S, Cl, Na, K, etc., these impurities can react with O or NaCl in the air (high content of NaCl over the coast or over the ocean) during combustion, and a mixed salt film such as Na2SO4 and NaCl is deposited on the surface of components, which is easy to cause hot corrosion of superalloy components.
Two different morphologies were observed on alloy surfaces, namely compact finer-grain crystalline and porous coarse-grain crystalline, as presented in Fig. 2.
The morphologies of The New alloy and FGH96 were observed on alloy surfaces, showing that more compact finer-grain crystalline film formed on the surface of The New alloy compared with FGH96.
A large number of mixed oxides formed in the external corrosion zone of FGH96, but no continuous oxides formed.

Based on the reaction process, it is possible to predict the rate of oxidation and corrosion of the number of moles of electrons of an element [4].
The number of valence electrons (ni) of the element aluminum with atomic number 13 is equal to the number of electrons.
Addition of Zn can significantly improve the grain size of metal substrates, consistent with previous findings [17].
Furthermore, the high grain boundary density induced by fine particles is also beneficial to improve the degradation behavior.
Acknowledgement This research was financially supported by mentoring Professor granted program of Engineering Faculty of Brawijaya University through contract number: 08/UN10.F07/H.PN/2022 References [1] S.

For the 1Cr18Ni9Ti sample: from the perspective of impact frequency, the deformation rate of the gridding in every layer is largest in initial thousands of times, with the increasing number of impact, deformation rate decrease gradually, until zero; View from the layer in coordinates, more closer to the surface gridding layer, the deformation rate is larger, The average deformation rate of the gridding decreases continuously with the increasing layers deep.
After a certain number of repeated impact, the metallographic structure of Ni-2 laser cladding coating component was observed by TEM after cutting, brigandine sample, grinding, polishing and aqua ragia corrosion, which was shown in Fig.5.
The broken grain is the performance of deformation. 20 20 Before repeated impact After repeated impact Fig.5 Metallographic organization chart of Ni-2 laser coating before and after repeated impact Conclusions (1) There is obvious difference between the two repeated impact tests of 1Cr18Ni9Ti sample and 1Cr18Ni9Ti sample with Ni-2 laser cladding coating.

Unfortunately, the high carbon and alloy contents in the tool steels inherently give rise to carbide segregation at grain boundaries and a coarse-grained microstructure by conventional processing, such as casting, hot working, and cooling [1].
While there have been a number of studies on LSM in modifying the microstructure of tool steels [20-27,30,32,33], there have been very few studies on improvement of both hardness and corrosion resistance.
Hardness was high because austenite was strengthened by solid solution, dislocation and smaller grain size
But the hardness of LM-440C is still high because austenite is strengthened by solid solution, dislocations and small grain size [25].
The importance of Mo is similar to that in the pitting resistance equivalent number (PREN) of the stainless steels: PREN = [Cr] + 3.3[Mo] + 16[N] This is a reasonable relationship reported by many researchers [52,53].

The diffusivity of Pt, Ni and Al being dependant on the stoichiometry of the -NiAl coating, different metal particles may precipitate mainly at the NiAl grain boundaries.
In addition, many pores appear randomly distributed in the top area and aligned at the coatings' grain boundaries in the central zone.
From these values, it can be concluded that Ni, Cr, Co and Ta can diffuse outwardly at a similar rate as no grain boundaries exist in the alloy.
Many precipitates especially Cr, Co, Ta and W have been also shown to occur at the outer coating grain boundaries.
However, in another outwardly grown (Ni,Pt)Al coating, no significant number of precipitates was reported [23].

This has been achieved by effectively managing a number of factors, including the control of impurity elements, such as hydrogen and phosphorous that are present during the preparation of Li-containing alloys, as well as using grain refining elements such as Mn and Zr.
These help by assisting in pinning grain boundaries.
This was shown by the large number of pit sites surrounding the intermetallic particles.
Some of the pits on AA2024-T3 were a similar size to those on AA2099-T8E77 (~100 x 100 µm), however, most were smaller and the number of pits was also less, as illustrated in Fig. 1c.
Of the phases that are detrimental to corrosion, AA2024-T3 possesses the potential to include a number; Al2Cu and Al2Cu-Mg, whereas AA2099-T8E77 can also include; Al3Li and Al2CuLi.

The number of cycles for each of the specimens has been established at 4000.
The dendrite grains at the boundary between the remelted and heat affected zones (RZ/HAZ) are fine, which is caused by the high temperature gradient.
With the use of the testing device, the coefficient of friction in the function of cycle number, has been evaluated (Fig. 3).
The sudden changes of the coefficient of friction that appear along some curves may result from the contact of the counter-specimen (Al2O3 ball) with the grains of adequate, undissolved in the laser treatment carbides.
The plot of the coefficient of friction depending on the number of cycles during the pin-on-disc test of X40CrMoV5-1 steel after alloying with TaC.

(2) Particle analysis Test of fine-grained soil 0.075mm below is conducted using laser particle size analyzer and test results are shown in the figure below, which reflects that the microscopic structure of the cohesive soil is stable aggregates cemented by free oxides.
This is an important feature of high water content cohesive soil that is different from the general fine-grained soil. 2) According to the test statistics, the maximum intensity moisture content is generally less than the optimum moisture content from 0.2 to 0.3 in consistency, and the moisture content is more than from 6% to 10%.
Fig.7 Relationship between resilient modulus and freeze-thaw cycles (2) Relationship between resilient modulus and freeze-thaw cycle number Resilient modulus for the different compaction degree is shown in Figure 8.
Fig.8 Relationship between resilient modulus and the freeze-thaw cycle number It can be seen that the resilient modulus under each compaction degree decreases with the increase of freeze-thaw cycle number.
Table 3 Service life prediction of the highway under different subgrade strength ratio Strength ratio Load condition Maximum bending stress /MPa cleavage strength/MPa Fatigue effects number/ Million times Service life/year 1.5 standard load 0.18 0.6 2.64E+05 68.4 overload 0.20 0.6 5.82E+04 52.6 1 standard load 0.22 0.6 1.48E+04 38.5 overload 0.25 0.6 2.37E+03 20.5 0.75 standard load 0.25 0.6 2.24E+03 20.0 overload 0.29 0.6 3.55E+02 6.8 0.5 standard load 0.30 0.6 1.82E+02 4.0 overload 0.34 0.6 2.98E+01 0.8 Conclusions Through analysis of long-term performance of high water content soil subgrade, conclusions are made as follows: (1) High water content cohesive soil has such physical and mechanical properties as natural moisture content is generally between 20% and 45%, liquid limit is between 40% and 60%, clay content is generally over 40%, permeability coefficient is between 10-7～10-8cm/s, the CBR value is less than 5, the optimum moisture content is about 20 percent and maximum dry density