Open Access Thesis
Cast-iron -- Metallurgy; Cast-iron -- Mechanical properties;
The problem addressed in this study analyzed various properties of cast iron with high aluminum content. This grade of cast iron was projected for use in the automotive industry. The benefits provided with high aluminum content are lower specific gravity and relatively inexpensive source materials with the potential of achieving high temperature properties.
The purpose of the study was to select suitable source materials and determine an effective melting technique, to investigate metallurgical structure and mechanical properties at given chemical composition, and, finally, to provide elaborate results.
The design of the experiment included the following steps: (a) selection and preparation of source scrap materials; (b) processing of the cast iron with high aluminum content in air-induction furnace; (c) record temperature fluctuations while the iron solidifies; ( d) determine melt losses to achieve desired bulk chemical composition of the iron; ( e) prepare and perform a metallographic analysis of the samples from representative regions of the casting; (t) conduct the tests of tensile strength and hardness.
Necessary data was collected during the all stages of the experiment. The results were analyzed, and it was found that: (a) the cast iron with average aluminum content around 25 wt. % exhibits tensile strength comparable to the gray iron; (b) metallographic analysis revealed the presence of two major precipitates: graphite and carbide phase, which was identified as Al4C3; (c) specific gravity of the iron was measured as 5.62 g/cm3 , which is 21 % less than gray iron and up to 30 % less than other materials used in automotive industry.
Thus, the technology of melting iron aluminum with high carbon content was successfully tested in semi-industrial settings. Various analyses of the iron showed that its multi-phase microstructure included a matrix phase of iron-aluminum solid solution, aluminum carbide and graphite precipitates. Graphite precipitates, caused by high carbon content, lowered the tensile strength of the alloy.
Other advantageous properties of this alloy, such as resistance to corrosion and conservation of its tensile strength at elevated temperature are the matter of future research.
Year of Submission
Master of Arts
Department of Industrial Technology
Scott R. Giese
1 PDF file (89 pages)
©2009 Pavel Bizyukov
Bizyukov, Pavel, "Preliminary Investigation of Metallurgical Structure and Mechanical Properties of Cast Iron With High Aluminum Content" (2009). Dissertations and Theses @ UNI. 1294.