Investigation of the influences of heat treatment on the microstructures and thermal properties of Al-20Si alloy fabricated by powder extrusion

Zhang, Yongyun1; Feng, Shihui1; Ding, Chao1; Nodooshan, Hamid Reza Jafari1; Ye, Shulong1; Jiang, Feng1; Li, Zhong2; Gu, Meng1; Yu, Peng1

2020-10

10.1016/j.matchar.2020.110522

MATERIALS CHARACTERIZATION   影响因子和分区

1044-5803

1873-4189

Al-20Si alloy with high thermal conductivity and adequately low coefficient of thermal expansion is successfully produced by hot extrusion of pre-alloyed powder and used as a model material in investigating the influences of heat treatment on the thermal properties of the material. In the as-extruded samples, fine Si particles are distributed uniformly in the Al matrix. When the alloy is annealed at 250 degrees C or 400 degrees C for 2 h, neither the Al nor Si grains grow significantly, but the internal strain developed in extrusion is relieved. Therefore, thermal conductivity is improved to 148.0 W/(m center dot K) and the coefficient of thermal expansion is reduced to 17.3 x 10(-6)/K. With further increasing annealing temperature to 560 degrees C, the coarsening of Al and Si grains occurs. On one hand, it significantly reduces the grain boundaries and phase boundaries in the material, consequently further increasing the thermal conductivity to 174.8 W/(m center dot K). On the other hand, the coarsened structures lead to thermal stress during cooling, which offsets the constraining effect of Si on the thermal expansion of Al and results in an increase in the coefficient of thermal expansion.

Al-Si alloy ELECTRON BACKSCATTER DIFFRACTION Thermal conductivity MECHANICAL-PROPERTIES Coefficient of thermal expansion SI ALLOY Microstructures EXPANSION BEHAVIOR Heat treatment AL/SIP COMPOSITES Powder extrusion CONDUCTIVITY TEMPERATURE PRESSURE EVOLUTION FRACTION

SCI ; EI

英语

第一 ; 通讯

Shenzhen Science and Technology Innovation Committee[SGLH20161212155758670][KQJSCX20180322152424539] ; Shenzhen DRC project[[2018]1433]

Materials Science ; Metallurgy & Metallurgical Engineering

Materials Science, Multidisciplinary ; Metallurgy & Metallurgical Engineering ; Materials Science, Characterization & Testing

WOS:000571497800003

ELSEVIER SCIENCE INC

20203108996232

Thermal conductivity ; Aluminum alloys ; Grain boundaries ; Heat treatment ; Extrusion ; Silicon alloys ; Coarsening

Heat Treatment Processes:537.1 ; Aluminum Alloys:541.2 ; Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals:549.3 ; Thermodynamics:641.1 ; Materials Science:951

MATERIALS SCIENCE

Web of Science

1.Southern Univ Sci & Technol, Dept Mat Sci & Engn, Shenzhen 518055, Peoples R China;
2.Southern Univ Sci & Technol, Dept Mech & Energy Engn, Shenzhen 518055, Peoples R China

Zhang, Yongyun,Feng, Shihui,Ding, Chao,et al. Investigation of the influences of heat treatment on the microstructures and thermal properties of Al-20Si alloy fabricated by powder extrusion[J]. MATERIALS CHARACTERIZATION,2020,168.

Zhang, Yongyun.,Feng, Shihui.,Ding, Chao.,Nodooshan, Hamid Reza Jafari.,Ye, Shulong.,...&Yu, Peng.(2020).Investigation of the influences of heat treatment on the microstructures and thermal properties of Al-20Si alloy fabricated by powder extrusion.MATERIALS CHARACTERIZATION,168.

Zhang, Yongyun,et al."Investigation of the influences of heat treatment on the microstructures and thermal properties of Al-20Si alloy fabricated by powder extrusion".MATERIALS CHARACTERIZATION 168(2020).