FEATURES OF OBTAINING A GRADIENT STRUCTURE IN CAST IRON BILLETS FOR GLASS PACKAGING INDUSTRY MOULDS

Procesi littâ, 2024, Vol 4 (158), 3-13

Abstract

Glass manufacturing is an important industry sector that produces a wide range of environmentally eco friendly products, and from building glass to laboratory equipment.However, the production of glass containers requires the use of special equipment - glass moulds that are subjected to significant thermal and mechanical stress during operation, which leads to their rapid wear. Current
technologies do not ensure a long service life for glass moulds. One of the main tasks is to develop effective methods for obtaining a gradient structure in cast iron billets with a ferrite metal matrix, which will significantly improve their characteristics and extend their service life. A technology has been developed to create a gradient structure in cast iron billets in the cast state, which improves the heat resistance and mechanical properties of castings. The technology was tested on heat-resistant cast iron, which is known for its high thermal conductivity and strength. To obtain the gradient structure, the company used pour over and in-mold methods of cast iron with modifiers and chillers of different thicknesses.
Main research results:
1. A targeted change in the structure of cast iron billets was achieved through the use of pour over and in-mold methods of processing of cast iron using SB5 and VL63(M) modifiers. This made it possible to create a gradient structure that differs from the traditional homogeneous structure.
2. The use of 10, 20 and 30 mm thick cast iron chillers made it possible to control the size and shape of the graphite inclusions. For the second blow moulds, an optimum structure with lamellar graphite was achieved, which provides the high thermal conductivity required at high temperatures. 
3. The formation of spheroidal graphite in the surface layers of the first blow moulds was achieved, which increased the resistance to mechanical stress and the durability of the moulds. The degree of spheroidization of spheroidal graphite reached 70-80%.
4. Studies have shown a smooth transition from lamellar to spheroidal graphite, which improves thermal conductivity and wear resistance of moulding sets.
5. Metallographic studies have confirmed the presence of a stable ferrite metal matrix that is resistant to cyclic loads, which avoids additional heat treatment and reduces production costs.
Thus, the introduction of a gradient structure in cast iron billets for glass moulds has significantly improved their performance properties and opens up new opportunities for optimizing production processes.