The invention discloses a
casting method capable of preventing a precise
investment casting from generating hot-spot shrinkage holes. The
casting method comprises the following steps that: a dead
head position is determined according to a conventional method, and a dead head
metal patch is replaced by a shell patch at a part, needing to be provided with the dead head
metal patch, of the precise
investment casting, wherein the material of the shell patch is
mortar paste prepared from back layer
slurry, back layer
powder and back layer sand in a
mass ratio of 1:1:5; the shell patch is bonded by the
mortar paste, wherein before bonding, a layer of back layer
slurry is brushed at a part needing to be bonded with the
mortar paste at first, and then the wedge-shaped shell patch is formed according to a method that the thickness at a dead head is greater than that at a hot spot; after that, shell
roasting and pouring are performed. Due to the action of the shell patch, the dead head and the hot spot keep a good feeding channel, thus realizing a mode of sequentially solidifying from the hot spot to the dead head, and then preventing the hot spot of the
casting from generating the shrinkage holes. According to the method, patch
metal for the casting is saved, the product yield of the process increases, and the visual quality of the casting is guaranteed.