Bifilm Inclusions in High Alloyed Cast Iron

Abstract

Continuous improvement in the quality of castings is especially important since a cast without defects is a more competitive product due to its longer lifecycle and cheaper operation. Producing quality castings requires comprehensive knowledge of their production, crystallization process, and chemical composition. The crystallization of alloyed ductile iron (without the addition of magnesium) with oxide bifilm inclusions is discussed. These inclusions reduce the quality of the castings, but they are a catalyst for the growth of spheroidal graphite that crystallizes in their vicinity. The research was carried out for cast iron with a highly hyper-eutectic composition. Scanning electron microscopy and EDS analysis were used in the research. A detailed analysis of the chemical composition was also carried out based on the spectrometric method, weight method, etc. Based on the obtained results, a model of spheroidal graphite crystallization near bifilm inclusions was proposed. The surface of the analyzed graphite particles was smooth, which suggests a primary crystallization process. The phenomenon of simple graphite and bifilm segregation towards the heat center of the castings was also documented.

Crystallization of Intermetallic Phases Fe2Si, Fe5Si3 for High Alloyed Cast Irons

“…The tests were conducted in laboratory conditions. Two-stage metallurgical processing of liquid metal was used [15]. The tests were carried out using a medium-frequency induction furnace (PI25, ELKON LLC, Rybnik, Poland).…”

“…The material prepared this way was used in the proper melt in the next step. Double melting was conducted to eliminate gas dissolved in the liquid alloy [15]. During the initial melting, samples for carbon content analysis were collected.…”

“…It also shows abrasion resistance. However, its most prominent advantage is its high resistance to the corrosive effects of many acids (sulfuric and nitrogen) and solutions of copper and chlorine [15]. High silicon cast iron is used to produce electrodes for cathodic protection systems [16,17].…”

Quality, Microstructure, and Properties of Metal Alloys

“…The work presented in this Special Issue [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] demonstrates the possibilities of further improving the microstructure quality and mechanical properties of metal alloys.…”

“…The analysis was also carried out on foundry metal alloys. The crystallization of alloyed ductile iron (without the addition of magnesium) with oxide bifilm inclusions is discussed [13]. Based on the obtained results, a model of spheroidal graphite crystallization near bifilm inclusions was proposed.…”