Industrial components of the commonly used cast iron range: 2.5 ~ 4.0% C and 1.0 ~ 3.0% Si, 0.5 ~ 1.4% Mn, 0.01 ~ 0.20% S. In addition, still contain Cr, Mo, V, Cu, Al the element.
HuiKouTie casting of the organizational characteristics is to have the graphite flake, the matrix organization are divided into three types: ferrite, pearlite, ferrite pearlite +.
Usually, C and Si can effectively promote graphitization elements. In order to ensure that cast iron casting can get ash, and not get too much and bulky graphite piece, usually will cast iron composition control of in 2.5 ~ 4.0% C and 1 ~ 2.5% Si.
Al, Cu in cast iron, Ni, Co elements will also proote graphitization. S, Mn, Cr, W, Mo, V, carbide form elements is stop graphitization. S not only strong stop graphitization, still can reduce the mechanical properties of the cast iron and liquidity. General control in 0.1 ~ 0.15% below. Mn although can stop graphitization, but he can and S generation MnS, the content of 0.5 ~ 1.4%.
HuiKouTie can be regarded as a steel base and the inclusion of flake graphite. So graphite piece is less, the thinner, more even, the mechanical properties of the cast iron is more high. In the content of graphite cast iron with C and Si is related to, especially the C. But contain C and Si low amount of cast iron will increase chilling tendency, form white or hemp mouth organization.
Usually in order to improve mechanical properties of cast iron, can adopt "inoculated" namely before casting in the molten iron into small "inoculant". So in the iron solidification process produces a lot of artificial crystal nucleus, in order to promote the form of graphite nuclear and crystallization. Not only can prevent chilling, and still can make the crystallization of graphite piece of significant refined.
The most commonly used inoculants for ferrosilicon and calcium silicon alloy, addition amount for the total weight of molten iron general of around 0.4%. After the inoculated the cast iron, not only its strength has greatly improved, and the model form and toughness has also improved.