Mechanical properties of casting ferrite
1. The mechanical properties of malleable iron castings are affected by some factors, including cooling rate during solid solution, chemical composition, heat treatment, casting design, cross-section thickness, gate, riser, and white gate location and effectiveness.
2. Because of the complexity of these factors in affecting the performance of the final product, there is no precise quantitative relationship between the performance of the iron at different positions of the same casting or the casting and the sample cast from the same molten iron. When this type of quantitative relationship is important and its specific purpose must be known, the quantitative relationship can be determined by experiments.
3. Specimen are specified as malleable iron tensile test bars. The diameter of the test section is "/sin. [16mm]. This section is a typical section for general operation of malleable iron castings. In addition, the initial condensation of malleable iron As a homogenizing treatment, the heat treatment inherent in the manufacture of malleable iron tends to reduce the sensitivity of the section. Therefore, it is not feasible to test with the precise properties of a given casting. This is manufactured according to any typical casting. The standard test bar should provide a performance similar to the actual one, which should be the expected average solid malleable iron casting.
4. If malleable iron castings are used for welding, the microstructure of the affected iron should be marked, especially for the heat-affected zone. Therefore, due to the possible adverse effects on the performance of the castings, the welding of malleable iron castings should be strictly controlled by metallography, followed by appropriate post-weld heat treatment to improve the elongation, impact resistance and workability (the workability is possible As a result, the reduction is minimized, especially in the vicinity of welding. However, it is generally considered improper to connect castings with similar castings or with other materials through off-site fusion welding or manufacturing equipment (the equipment does not fully test the entire complete part).