Directions for the development of a methodology for regulating the chemical composition and properties of cast iron in foundry production based on a probabilistic approach

Abstract

From the standpoint of systemic and structural-functional approaches, the state and prospects of development of the methodology for regulating and predicting the chemical composition and mechanical properties of grey synthetic cast iron intended for casting production are analysed. Attention is focused on the key intersections of the technological process of manufacturing castings for critical applications. The features, disadvantages, and advantages of the known methods for calculating the charge and adjusting the percentage of chemical elements in the cast iron composition directly during its melting are considered. Ways to take into account the instability of the chemical composition of scrap metal, ferroalloys, and other materials when forming the charge to ensure the quality of pig iron in accordance with the requirements of finished product standards are shown. A promising way to solve this problem in foundry is to use a probabilistic approach and the Monte Carlo method. The article presents formulas for calculating the strength and hardness of cast iron castings with lamellar graphite depending on its carbon equivalent and degree of eutecticity. The peculiarity of the proposed formulas, which gives them enhanced reliability and validity, is that the carbon equivalent and the degree of eutecticity of cast iron in them are determined by the Monte Carlo method using a probabilistic approach with regard to the consideration of the ranges of variation of the content of chemical elements in the cast iron composition regulated in the standard for foundry products. It is noted that the widespread use of thermal derivative express analysis of liquid cast iron in industry is constrained by the lack of a database of reference cooling curves with certain property indicators (chemical composition, microstructure, mechanical and other properties) of cast irons at foundries. Keywords: foundry, cast iron, chemical composition, properties, control, regulation, methodology.