中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 25 No. 7 July 2015 |
（Department of Materials Science and Engineering, Faculty of Engineering, Shahid Chamran University of Ahvaz,
Ahvaz 61357-83151, Iran）
Abstract:The microstructure and mechanical properties of the gas tungsten arc welded cast A356 alloy were investigated with fillers ER1100, ER4043, ER4047 and ER5356 under the pulse frequencies of 1, 3 and 5 Hz. Results showed that the filler metal and pulse frequency affected the grain structure of fusion zone considerably. The highest fraction of eutectic (44%) was formed with filler ER4047. Tensile fracture of all specimens indicated that fracture did not occur in the fusion zone. The greatest impact toughness (about 4 J) was achieved for the welds with filler ER4047 while the largest hardness (HV 90) was obtained with filler ER5356.
Key words: cast A356 alloy; gas tungsten arc welding; microstructure; hardness; impact energy
