Evaluating the mechanical properties of grain-boundary phases in nano- and submicrocrystalline materials using a model of an elastic multilayer periodic medium

The results of the research of structure and properties of a composite compact from 13 Cr – 2 Мо and BN powders depending on the concentration of boron nitride are provided. It is shown that adding boron nitride in an amount of more than 2% by weight of the charge mixture leads to the formation of extended grain boundary porosity and finely dispersed BN layers in the structure, which provides a high level of wearing properties of the material. The effect of boron nitride concentration on physical and mechanical properties is determined. It was found that the introduction of a small amount of BN (up to 2 % by weight) into the compacts leads to an increase in plasticity, bending strength, and toughness by reducing the friction forces between the metal powder particles during pressing and a more complete grain boundary diffusion process during sintering. The formation of a regulated structure-phase composition of powder compacts of 13 Cr – 2 Mо – BN when the content of boron nitride changes in them allows us to provide the specified physical and mechanical properties in a wide range. The obtained results of studies of the physical and mechanical characteristics of the developed material allow us to reasonably choose the necessary composition of the powder compact for sealing structures of the flow part of steam turbines, depending on their operating conditions.

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Realization of structural evolution in grain boundary, solute redistribution and improved mechanical properties by adding TiCnps in wire and arc additive manufacturing 2219 aluminium alloy

Journal of Materials Research and Technology ◽

10.1016/j.jmrt.2021.01.030 ◽

2021 ◽

Vol 11 ◽

pp. 834-848

Author(s):

Peng Jin ◽

Yibo Liu ◽

Fuxiang Li ◽

Junzhao Li ◽

Qingjie Sun

Keyword(s):

Mechanical Properties ◽

Additive Manufacturing ◽

Grain Boundary ◽

Aluminium Alloy ◽

Structural Evolution ◽

Solute Redistribution

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Effect of Aging Treatment on Properties and Microstructure of an Al-7.5Zn-1.3Mg-1.4Cu-0.12Zr Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.638-642.273 ◽

2010 ◽

Vol 638-642 ◽

pp. 273-278 ◽

Cited By ~ 2

Author(s):

Xi Wu Li ◽

Bai Qing Xiong ◽

Yon Gan Zhang ◽

Guo Jun Wang ◽

Zhi Hui Li ◽

...

Keyword(s):

Mechanical Properties ◽

Electrical Conductivity ◽

Grain Boundary ◽

Response Rate ◽

Aging Treatment ◽

Aging Response ◽

Peak Aging

In this study, the effect of various aging treatment (T6 and T7 treatment) on the mechanical properties, electrical conductivity and the microstructure of an Al-7.5Zn-1.3Mg-1.4Cu-0.12Zr alloy has been investigated. The results show that with elevating the aging treatment temperatures, the aging response rate is greatly accelerated. When T6 temper is performed at 140°C for 12h, as compared to peak aging for 24h at 120°C, the UTS and the corresponding Elongation values keep the same level, whereas the TYS and the electrical conductivity obviously increase by 5% and 9%, which is up to 560 MPa and 22.6 MS/m, respectively. And there are clear PFZs along the grain boundary and slightly coarser precipitates inside the grain. GPI zones, GPII zones and η' phases are major precipitates for the alloy under T6 condition. When T7 temper is performed on the alloy, the main precipitates are GPII zones, η′ and η phases. The coarser precipitates inside the grain and discontinuous grain boundary precipitates are favorable to electrical conductivity, which decrease the strength of 5~17% compared to T6 treatment. After T76 treatment (i.e., 110°C/6 h + 160°C/6 h), the UTS, TYS, Elongation and electrical conductivity values were 540 MPa, 510 MPa, 16.7% and 23.5 MS/m, respectively.

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Effect of Nonequilibrium Grain Boundary Segregation of Alloying Elements on Mechanical Properties in Fe–5Mn–9Ni–5Mo Alloy

Materials Transactions JIM ◽

10.2320/matertrans1989.37.56 ◽

1996 ◽

Vol 37 (1) ◽

pp. 56-62 ◽

Cited By ~ 7

Author(s):

N. H. Heo

Keyword(s):

Mechanical Properties ◽

Grain Boundary ◽

Boundary Segregation ◽

Alloying Elements ◽

Grain Boundary Segregation ◽

Segregation Of Alloying Elements

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Grain boundary character correlated carbide precipitation and mechanical properties of Ni-20Cr-18W-1Mo superalloy

Materials Science and Engineering A ◽

10.1016/j.msea.2016.05.028 ◽

2016 ◽

Vol 667 ◽

pp. 391-401 ◽

Cited By ~ 19

Author(s):

Yinben Han ◽

Xiangyi Xue ◽

Tiebang Zhang ◽

Rui Hu ◽

Jinshan Li

Keyword(s):

Mechanical Properties ◽

Grain Boundary ◽

Carbide Precipitation ◽

Boundary Character ◽

Grain Boundary Character

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Effect of Post Weld Heat Treatment on Fusion and Heat Affected Zone Microstructure and Mechanical Properties of Inconel X-750 Welds

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.214.108 ◽

2011 ◽

Vol 214 ◽

pp. 108-112 ◽

Cited By ~ 3

Author(s):

Prachya Peasura ◽

Bovornchok Poopat

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Grain Size ◽

Grain Boundary ◽

Weld Metal ◽

Heat Affected Zone ◽

Aging Temperature ◽

Post Weld Heat Treatment ◽

High Aging Temperature ◽

Zone Microstructure

The Inconel X-750 indicates good hot corrosion resistance, high stability and strength at high temperatures and for this reason the alloy is used in manufacturing of gas turbine hot components. The objective of this research was study the effect of post weld heat treatment (PWHT) on fusion zone and heat affected zone microstructure and mechanical properties of Inconel X-750 weld. After welding, samples were solutionized at 1500 0C. Various aging temperature and times were studied. The results show that aging temperature and time during PWHT can greatly affect microstructure and hardness in fusion zone and heat affected zone. As high aging temperature was used, the grain size also increased and M23C6 at the grain boundary decreased. This can result in decreased of hardness. Moreover excessive aging temperature can result in increasing MC carbide intensity in parent phase (austenite). It can also be observed that M23C6 at the grain boundary decreased due to high aging temperature. This resulted in decreasing of hardness of weld metal and heat affected zone. Experimental results showed that the aging temperature 705 0C aging time of 24 hours provided smaller grain size, suitable size and intensity of MC carbide resulting in higher hardness both in weld metal and HAZ.

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Microstructure and Mechanical Properties of Mo2FeB2 Based Cermets Containing SiC Whisker

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.625.304 ◽

2012 ◽

Vol 625 ◽

pp. 304-307 ◽

Cited By ~ 1

Author(s):

Hai Zhou Yu ◽

Wen Jun Liu ◽

Lian Ying ◽

Min You

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Grain Boundary ◽

Grain Growth ◽

Rupture Strength ◽

Boundary Migration ◽

Grain Boundary Migration ◽

Hard Phase ◽

Maximum Hardness ◽

Vacuum Sintering

Four series of cermets with the SiC whisker content between 0 and 1.0 wt.% were prepared by vacuum sintering. The transverse rupture strength (TRS), hardness (HRA) and fracture toughness (KIC) were also measured. The SiC whiskeraddition was located at the grain boundaries, which prevented grain boundary migration and restrained the grain growth. However, an increasing SiC whisker content decreased the wettability of the binder on the Mo2FeB2 hard phase. The highest TRS and fracture toughness was found for the cermets with 0.5 wt.% SiC whisker addition, whereas the cermets without SiC whisker addition exhibited the maximum hardness.

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