Effect of extrusion temperatures on the microstructures, mechanical properties and thermal properties of PM Al-20Si alloy

Ding，Chao; Yu，Peng

2022-05-15

10.1016/j.jallcom.2022.163979

JOURNAL OF ALLOYS AND COMPOUNDS   影响因子和分区

0925-8388

1873-4669

Al-20Si alloy is fabricated by extruding pre-alloyed powder at different temperatures ranging from 350° to 550°C. Morphologies of the Si phase, mechanical properties and thermal properties of the alloy are influenced by extruding temperature. The alloy extruded at 350 °C mainly contains fine eutectic Si. Although its fine structure imparts high strength to the alloy, it is not stable in high-temperature CTE test and tends to agglomerate into large Si lumps due to Oswald ripening effect, therefore offsetting the restriction effect of Si on the thermal expansion of Al and thus increasing the CTE of the alloy. In contrast, the alloy extruded at 550 °C exhibits primary Si phase, which is large in size and more stable in the CTE test. Moreover, it has in-situ formed amorphous/δ * - AlO at the grain boundaries which reduces the CTE of the alloy further. As a result, the alloy fabricated at 550 °C exhibits the best combination of thermal properties (i.e. TC 184.5 WmK and CTE 20.9 ×10 K at 400 ℃).

Al-20Si Hot extrusion Mechanical properties Microstructure Thermal properties

SCI ; EI

英语

第一 ; 通讯

Shenzhen Science and Technology Innovation Committee[KQJSCX20180322152424539]

Chemistry ; Materials Science ; Metallurgy & Metallurgical Engineering

Chemistry, Physical ; Materials Science, Multidisciplinary ; Metallurgy & Metallurgical Engineering

WOS:000779660500003

ELSEVIER SCIENCE SA

20220511575148

Alumina ; Aluminum alloys ; Aluminum oxide ; Extrusion ; Grain boundaries ; High strength alloys ; Silicon alloys ; Thermal conductivity ; Thermal expansion

Metallurgy:531.1 ; Aluminum Alloys:541.2 ; Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals:549.3 ; Thermodynamics:641.1 ; Inorganic Compounds:804.2 ; Materials Science:951

MATERIALS SCIENCE

2-s2.0-85123760406

Scopus

Department of Materials Science and Engineering,Southern University of Science and Technology,Shenzhen,518055,China

Ding，Chao,Yu，Peng. Effect of extrusion temperatures on the microstructures, mechanical properties and thermal properties of PM Al-20Si alloy[J]. JOURNAL OF ALLOYS AND COMPOUNDS,2022,903.

Ding，Chao,&Yu，Peng.(2022).Effect of extrusion temperatures on the microstructures, mechanical properties and thermal properties of PM Al-20Si alloy.JOURNAL OF ALLOYS AND COMPOUNDS,903.

Ding，Chao,et al."Effect of extrusion temperatures on the microstructures, mechanical properties and thermal properties of PM Al-20Si alloy".JOURNAL OF ALLOYS AND COMPOUNDS 903(2022).