一、离心铸件的凝固与补缩: 在离心铸造中为了要得到致密的铸件,应力求形成由外表面向内表面的顺序凝固,内表面起着补缩冒口的作用,对铸件进行补缩。应尽量避免形成双向凝固,即当凝固阵面由外向内推进时,内表面亦形成凝固层并向外生长,以致在二个凝固阵面相遇处形成集中的缩松区。在生产中影响凝固方向的因素有两个方面: ①传热方面:由于铸型的吸热,以及铸型外表面与周围介质(空气或冷却水)间之热交换,使铸件中之热量通过外表面传递出去。假如采用砂型、而砂层的厚度等于或超过铸件的壁厚时,在铸件 First, centrifugal casting solidification and shrinkage: Centrifugal casting in order to get dense castings, should strive to form the outer surface to the inner surface of the order of solidification, the inner surface plays the role of feeding riser, the casting for shrinkage. Should try to avoid the formation of two-way solidification, that is, when the solidification front pushed forward from the outside, the inner surface also forms a solidified layer and grows outward, so that the two solidification fronts met to form a concentrated shrinkage zone. In the production of the factors that affect the direction of solidification has two aspects: ① heat transfer: due to the heat absorption of the mold, and the outer surface of the mold and the surrounding medium (air or cooling water) between the heat exchange so that the casting of heat The outer surface is passed out. If the use of sand, and sand thickness equal to or exceeding the wall thickness of the casting, the casting