The experimental results show that the method may increase the tensile strength by 50 Mpa and the hardness by 20 HB of gray cast iron, decrease the chilling tendency, improve the graphite morphology, reduce the wall thickness sensitivity and raise the content of A graphite morphlogy by increasing the sulphur c.

Taking HT250, QT450-10 as experimental materials and the traditional inoculant as comparative object, the influence of "Ba" inoculant on the fading-resistance and the experiment shows: Ba inoculant can reduce the chilling tendency in cast iron, increase the number of eutectic colong and alleviate the producing of D-type graphite.

To boost our economy,a complex of policies must be implemented to increase people’s marginal rate of consumption and decrease marginal rate of imports as well as cutting tax.