所谓的”七一”型芯,就是水玻璃砂用氯化铵水溶液浸润硬化的芯子。过去,由于熔模精密铸造一直没有园满地解决型芯的问题,有些复杂的零件还是铸造不出来,这就使熔模精密铸造生产受到了一定的限制。采用“七一”型芯进一步完善了熔模精密铸造工艺,大大扩大了它的应用范围。 The so-called “seven one” core, is sodium silicate sand with sodium chloride solution impregnated hardened core. In the past, since the investment casting has not been satisfactorily solved the problem of core, some of the complex parts can not be cast, which makes the casting investment casting has been subject to certain restrictions. The use of “71” core to further improve the investment casting process, greatly expanding its scope of application.