Casting technology is the technology and method to produce castings by applying casting related theory and system knowledge. Including casting process, pouring system, feeding system, air vent, chilling system, special casting process and so on. It is a process that liquid alloy is injected into the mold cavity which is suitable for the size and shape of the part to make it cool, solidify and prepare the casting. With the development of modern science and technology, castings are required to have high mechanical properties, dimensional accuracy and low surface roughness value; some special properties, such as heat resistance, corrosion resistance, wear resistance, etc., are also required to have short production cycle and low cost. Reasonable casting structure is the premise of obtaining high quality castings, and the fundamental method of simplifying casting process, increasing productivity and reducing production cost. The structure of parts to be cast should not only meet the requirements of working performance and mechanical properties, but also meet the basic requirements of casting process, method and alloy casting performance, so as to achieve the effect of high quality, high yield and low consumption.
The selection of materials for mechanical parts is a complex problem, which needs to be based on the knowledge of engineering material theory and its application theory, clear objectives and restrictions, carry out specific analysis, carry out necessary tests and comparison of material selection schemes, and finally determine the material selection scheme. Generally, the principle of “usability, rationality, economy and technicality” shall be followed .
The parts of the support table are mainly used to bear medium static load, that is to say, they support other parts of the machine when they are working, and they are often in the state of compressive stress, which requires compression resistance and wear resistance, so they are made of gray cast iron HT150.
Grey cast iron is a kind of cast iron with gray section and carbon mainly in the form of flake graphite. And its carbon and silicon content is high (carbon 3.0% – 3.7%, silicon 1.8% – 2.4%), its molten iron can be poured directly after being discharged without any treatment. Gray cast iron has good anti-wear, vibration absorption and cutting performance, as well as good casting fluidity, strong ability to fill the cavity, which is conducive to the floating of gases and impurities in the metal slag. HT150 works under medium load, and the unit area pressure between friction surfaces is not more than 490kpa. Castings in general mechanical manufacturing, such as: strut, base, gearbox, tool rest, bearing seat, bearing slide, etc. [2]. According to the requirements of this design, the material of the parts of the support platform is gray cast iron HT150.
