Study on the Effects of Metallurgical and Processing Parameters on the Production of Compacted Graphite Cast Iron
Date Issued
2016
Date
2016
Author(s)
Lin, Kai-Wei
Abstract
The primary purpose of this research is to establish the optimal conditions for the production of compacted graphite cast iron by investigating the effects of metallurgical and processing parameters (types of compactizer, addition amounts of compactizer, holding time, holding temperature and late inoculation) on graphite morphology and mechanical properties of compacted graphite cast iron. The results show that, for a fixed C.E. value of 4.2% and addition amounts of 0.3% inoculant and 0.6% Mg-RE compactizer without late inculation, a carbide-free compacted graphite cast iron with 80~90% vermicularity can be obtained. For the same treatment condition, again a carbide-free compacted graphite cast iron but with lower vermicularity about 50~70% and was attained by conducting late inculation. In addition, flake graphite will generate when Mg-RE compactizer decayed at about 13~20 minutes after compactization and inoculation treatment, but lower holding temperature can slow down this phenomenon. Besides, compacted and spheroidal graphite cast iron can’t be reach by conducting late inculation after flake graphite generate. For using RE alloys as the compactizer, a fixed C.E. value of 4.2% and addition amounts of 0.3% inoculant and 0.6% RE compactizer without late inculation, compacted graphite cast iron with 40~70% vermicularity but with carbide can be obtained. For the same treatment condition, carbide can be eliminates by conducting late inculation and a carbide-free compacted graphite cast iron with lower vermicularity about 10~60% can be attained. RE alloys will decay at about 20~27 minutes after compactization and inoculation treatment due to less volatile. In terms of the optimal conditions for the production of compacted graphite cast iron, addition amounts of 0.3% inoculant and 0.6% Mg-RE compactizer without late inculation, a carbide-free compacted graphite cast iron with about 80~90% vermicularity can be obtained at about 13 minutes after compactization and inoculation treatment. In the other hand, addition amounts of 0.3% inoculant and 0.8%~1.0% RE compactizer with late inculation, a carbide-free compacted graphite cast iron with 60% vermicularity can be obtained at about 20 minutes after compactization and inoculation treatment.
Subjects
Compacted graphite cast iron
Vermicularity
Compactizer
Late inculation
Carbide
Type
thesis