负压吸附涂料层透气性的测试原理及方法

A Method for Determining the Permeability of Coating Used for Casting

提出了用负压吸附涂料层的方式测试涂料透气性的新方法，并推导出了在该方法下计算涂料透气性的数学表达式。对该方法的可靠性进行了实验验证，结果表明，该法所测数值对同一种涂料具有好的重现与稳定性；对涂料透气性的微小变化有好的敏感性；粘结剂量增加，涂料透气性下降。

This paper presents a new method in which the coating layer is absorbed by low vacuum for determining the permeability of coating used in casting. The mathematics function of determining the permeability has been derived and the permeability value of calculated from the function is comparable with others in molding sand standard. Then,the reliability of the method has been demonstrated through experiments. The results show that the permeability value is stable for one coating and sensitive for different coatings; The permeability of coatings will descend with the content of the binder increasing.