图1基座用于某产品的接收机上,为薄壁的板类零件,壁厚相差悬殊不大,最厚为10毫米,最薄为3毫米。材质为ZHSi80—3。铸件不允许有缩孔、气孔、夹渣、裂纹、冷隔、氧化皮等缺陷存在。图1示尺寸95腔体内涂覆(即镀耐磨银),涂覆后抛光到7时,表面针孔数每平方厘米不超过15个,其中直径小于0.3毫米的占80％。直径小于0.5毫米的占20％。 Figure 1 base for a product receiver, for the thin-walled board parts, wall thickness difference between the little difference, the maximum thickness of 10 mm, the thinnest of 3 mm. Material is ZHSi80-3. Casting does not allow shrinkage, porosity, slag, cracks, cold insulation, scale and other defects exist. Figure 1 shows the size of 95 cavity coating (ie wear-resistant silver), polished to 7 after coating, the surface pinhole no more than 15 per square centimeter, of which less than 0.3 mm in diameter accounted for 80%. Diameter less than 0.5 mm accounted for 20%.