Development and research of vermicular graphite cast iron

In the 1950s, kdmills and other scholars discovered vermicular graphite cast iron, but it did not attract attention at that time. It was not until the 1960s that real research began on it. In recent years, vermicular graphite cast iron is more and more found to be a new type of cast iron with application potential, and has developed rapidly in many countries. Vermicular graphite cast iron sacrifices part of the heat transfer performance in exchange for better fatigue resistance, high strength and high wear resistance than gray cast iron. The engine parts made of vermicular graphite cast iron have small volume and high strength. It has a good development prospect in the fields including key parts of power equipment.

However, due to the high strength, high tensile strength and relatively low thermal conductivity of vermicular cast iron, compared with gray cast iron, the tool replacement frequency increases and the tool life decreases. Conservative cutting parameters are often used in the actual machining process, which affects the productivity. These factors hinder the development of vermicular graphite cast iron. For example, when Guangxi Yuchai Co., Ltd. processes the vermicular graphite cast iron engine cylinder head, the cutting amount is small, the production efficiency is low, and the cutting tool is easy to break.

In China, some scholars began to study vermicular cast iron for a long time, mostly through experimental research to optimize cutting parameters in order to reduce the processing cost of vermicular cast iron. There are few studies on the dynamic mechanical behavior and cutting simulation of vermicular graphite cast iron. Therefore, it is necessary to study the dynamic mechanical behavior of vermicular cast iron, establish the constitutive equation of vermicular cast iron under the condition of high temperature and high strain rate, and guide the machining simulation of vermicular cast iron. At the same time, using the existing rich cutting examples, the appropriate cutting parameters are deduced by intelligent algorithm.