Lost wax casting believe everyone will encounter in the process of machining casting broken phenomenon, so that will make our casting productivity decline, so we in order to prevent this happens we need to know is what are the causes of influence. When the lost wax casting stainless steel castings in hulling, mechanical processing, and in the process of installation, often attack (namely) of brittle fracture to brittle fracture phenomenon.In case of this problem, will make the whole furnace casting scrap, cause there are many reasons for this phenomenon:Lost wax casting stainless steel castings brittle fracture occurred for the following reasons:1, lost wax casting, smelting of deoxidizer aluminum consumption is too high, it with the nitrification in the steel is easy to form aluminum nitride clip and make the brittle fracture of the casting.2, furnace lining building boric acid dosage is too high, and make the steel carbon boron compounds, namely "boron brittle".3, lost wax casting high carbon and other alloying elements beyond the promise to scale will increase the brittleness of steel, such as in pig iron carburization, feeding carefully, or the accounting, will bring into harmful elements.4, lost wax casting molten steel overheating and severe heat treatment operation wrong, coarse grains.