CuAlBe合金铸造气孔与工艺关系的探讨

The Exploration of the Relation between Gas Holes and Technology in CuAlBe Alloy Castings

本文通过试验，研究了ＣｕＡｌＢｅ合金铸造气孔缺陷与工艺的关系。试验表明，ＣｕＡｌＢｃ合金铸造时易吸气并产生气孔，熔炼和浇注工艺对气孔的形成有重要影响。大气下熔炼时合金液的含气量大，真空熔炼并结合吹氮（氩）等精炼除气工艺可显著降低合金液的含气量；而铸件最终是否存在气孔缺陷，关键在于浇注工艺。提高凝固速度、减少二次氧化夹渣，并造成自下而上的顺序凝固，可阻碍气泡的形成。因此，采用金属型或砂型加放冷铁，进行低温底注并点补冒口的浇注工艺，能大大减少气孔缺陷。

The technology effect on CuAlBe alloy castingg′ gas holes is studied.The results of experiments show that it is easy for CuAlBe alloy to absorb gas and form gas holes through it′s casting process,and it is closely related to smelting and pouring technology.For example,the vacuum smelting with blowing nitrogen(argon) can obviously decrease the amount of gas absorbed durign smelting CuAlBe alloy.In the other hand,the pouring way is the key that determines whether CuAlBe alloy castings remain gas holes. By the means of rapid and orderly solidification from bottom to top and decrease secondary oxides,the bubbles formation would become very difficult,so it′s found in fact that using metal model or sand model with chills,bottom gating to pour in lower temperature and pouring the riser late in pouring process can decrease CuAlBe alloy castings′ gas holes defects.