The failure of all 12 blades of an air fan was investigated by metallurgical and mechanical experiments and an examina-tion of the fracture surface. The experimental results show that the cast aluminium-silicon alloy ...The failure of all 12 blades of an air fan was investigated by metallurgical and mechanical experiments and an examina-tion of the fracture surface. The experimental results show that the cast aluminium-silicon alloy without any modification had a number of material defects, such as coarse grains, a loose structure, a large number of shrinkage holes, a long and thin bold-pin shaped silicon-phase, poor material strength and serious brittleness. In addition, installed on the spindle without elastic conjunction, blade No.10 vibrated and inevitably.spun off due to the large centrifugal force. Therefore, blade No.10 first cracked at the locking handle, then broke at the root, which caused all the other 11 blades to be broken by the crack of blade No.10.展开更多
基金Projects 2005A047 supported by the Science & Research Foundation for Youth of China University of Mining and Technology2007CB607605 by the National Basic Research Program of China
文摘The failure of all 12 blades of an air fan was investigated by metallurgical and mechanical experiments and an examina-tion of the fracture surface. The experimental results show that the cast aluminium-silicon alloy without any modification had a number of material defects, such as coarse grains, a loose structure, a large number of shrinkage holes, a long and thin bold-pin shaped silicon-phase, poor material strength and serious brittleness. In addition, installed on the spindle without elastic conjunction, blade No.10 vibrated and inevitably.spun off due to the large centrifugal force. Therefore, blade No.10 first cracked at the locking handle, then broke at the root, which caused all the other 11 blades to be broken by the crack of blade No.10.
