First-principles and experimental investigations on ductility/brittleness of intermetallic compounds and joint properties in steel/aluminum laser welding

The present study investigated the laser welding performance of Al-Fe aluminum alloy sheets with different contents of intermetallic compounds. Under the same welding parameters, the alloy of higher intermetallic compounds content has wide and deep weld pools with uniform sizes. The alloy of lower intermetallic compounds content has narrow and shallow weld pools with nonuniform sizes. The higher content of intermetallic compounds results in higher laser absorptivity and lower thermal conductivity, and then increases the effective absorbed energy during welding, which is beneficial to the formation of wide and deep weld pools. The distribution uniformity of intermetallic compounds influences the size uniformity of weld pools. In the alloy with lower content of intermetallic compounds, the nonuniform distribution of intermeallic compounds results in the formation of abnormal weld pool, leading to the nonuniform size of the weld pools. In the alloy with higher content of intermetallic compounds, uniform distribution of intermetallic compounds make the size of weld pools more uniform.

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Stability and Structures of Constitutional Defects in Nonstoichiometric Intermetallic Compounds by First-Principles Calculations

Materials Science Forum ◽

10.4028/www.scientific.net/msf.475-479.3111 ◽

2005 ◽

Vol 475-479 ◽

pp. 3111-3114

Author(s):

Masataka Mizuno ◽

Hideki Araki ◽

Yasuharu Shirai

Keyword(s):

Intermetallic Compounds ◽

First Principles ◽

Electronic Structures ◽

Stoichiometric Composition ◽

Electronic Structure Calculations ◽

First Principles Calculations ◽

Compositional Dependence ◽

Wide Range ◽

Formation Energies ◽

Structure Calculations

Some of intermetallic compounds exist in a wide range of concentration around the stoichiometric composition. First-principles electronic structure calculations have been performed for constitutional defects in non-stoichiometric CoAl and CoTi in order to investigate their stabilities and structural relaxations induced by constitutional defects. For the evaluation of stabilities of constitutional defects, the compositional dependence curves both of formation energies and of lattice parameters are obtained by the calculations employing supercells in various sizes. The lattice relaxations around constitutional defects are discussed by analyzing the change in electronic structures induced by constitutional defects.

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Effects of Co and Co + Mo additions on tensile properties of tungsten heavy alloys: first-principles study and experimental investigations

Powder Metallurgy ◽

10.1080/00325899.2021.1959694 ◽

2021 ◽

pp. 1-8

Author(s):

Ashutosh Panchal ◽

Ashish Pathak ◽

K. Venugopal Reddy ◽

P. A. Azeem ◽

T. K. Nandy ◽

...

Keyword(s):

Tensile Properties ◽

First Principles ◽

Experimental Investigations ◽

First Principles Study ◽

Heavy Alloys ◽

Tungsten Heavy Alloys ◽

Mo Additions

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First principles calculations of the optical and plasmonic response of Au alloys and intermetallic compounds

Journal of Physics Condensed Matter ◽

10.1088/0953-8984/26/30/305501 ◽

2014 ◽

Vol 26 (30) ◽

pp. 305501 ◽

Cited By ~ 12

Author(s):

V J Keast ◽

R L Barnett ◽

M. B Cortie

Keyword(s):

Intermetallic Compounds ◽

First Principles ◽

First Principles Calculations

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Mechanical and Thermal Conductivity Properties of Enhanced Phases in Mg-Zn-Zr System from First Principles

Materials ◽

10.3390/ma11102010 ◽

2018 ◽

Vol 11 (10) ◽

pp. 2010

Author(s):

Shuo Wang ◽

Yuhong Zhao ◽

Huijun Guo ◽

Feifei Lan ◽

Hua Hou

Keyword(s):

Mechanical Properties ◽

Thermal Conductivity ◽

Shear Modulus ◽

Bulk Modulus ◽

Intermetallic Compounds ◽

Elastic Constants ◽

First Principles ◽

Strengthening Phases ◽

Zr Alloy ◽

Zr Alloys

In this paper, the mechanical properties and minimum thermal conductivity of ZnZr, Zn2Zr, Zn2Zr3, and MgZn2 are calculated from first principles. The results show that the considered Zn-Zr intermetallic compounds are effective strengthening phases compared to MgZn2 based on the calculated elastic constants and polycrystalline bulk modulus B, shear modulus G, and Young’s modulus E. Meanwhile, the strong Zn-Zr ionic bondings in ZnZr, Zn2Zr, and Zn2Zr3 alloys lead to the characteristics of a higher modulus but lower ductility than the MgZn2 alloy. The minimum thermal conductivity of ZnZr, Zn2Zr, Zn2Zr3, and MgZn2 is 0.48, 0.67, 0.68, and 0.49 W m−1 K−1, respectively, indicating that the thermal conductivity of the Mg-Zn-Zr alloy could be improved as the precipitation of Zn atoms from the α-Mg matrix to form the considered Zn-Zr binary alloys. Based on the analysis of the directional dependence of the minimum thermal conductivity, the minimum thermal conductivity in the direction of [110] can be identified as a crucial short limit for the considered Zn-Zr intermetallic compounds in Mg-Zn-Zr alloys.

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