燃油壳体内部结构日趋复杂，采用 3D 打印低压砂型铸造工艺可满足其生产技术要求。 但是对砂型、涂料性能也提出了新要求。 本研究使用智能型砂强度仪、发气量测试仪以及透气性测定仪，分析了树脂含量对砂型强度、发气量和透气性的影响。 在此基础上，研究了涂料工艺对 3D 打印砂型发气量和透气性的影响。 当树脂含量为 1.2%，涂料波美度为 20°Bé，且浸涂时间为 4 s 时，砂型试样的抗压强度可达 3.6 MPa，发气量和透气性分别能达到 9.1 mL/g 和32 cm4/(g·min)，3D 打印砂型具有较好的强度、发气量及透气性。 优化后的验证生产表明，ZL114A 铝合金低压砂型铸造燃油壳体气孔缺陷得以消除。

The internal structure of fuel housing is becoming increasingly complex. The 3D-printed sand mold low-pressurecasting process can meet its production requirements. However, it also imposes new demands on the sand mold and coatingproperties. An intelligent sand strength tester, gas evolution tester, and permeability tester were used to analyse the effectsof the resin content on the sand mold strength, gas evolution, and permeability. Therefore, the influence of the coatingprocess parameters on gas evolution and permeability in 3D-printed sand molds was investigated. Under the conditions of a1.2% resin content, a 20°Bé Baumé degree for the coating and a 4 s dipping time, the compressive strength of the sandmold sample reaches 3.6 MPa, with a corresponding gas evolution rate and permeability coefficient of 9.1 mL/g and32 cm4/(g·min), respectively. The 3D-printed sand mold demonstrates favourable strength, gas evolution, and permeability.Validation production via optimized parameters demonstrates that gas porosity defects in ZL114A sand mold low-pressurecast fuel housings are eliminated.