Strength Prediction for Pearlitic Lamellar Graphite Iron: Model Validation

The present work provides validation of the ultimate tensile strength computational models, based on full-scale lamellar graphite iron casting process simulation, against previously obtained experimental data. Microstructure models have been combined with modified Griffith and Hall–Petch equations, and incorporated into casting simulation software, to enable the strength prediction for four pearlitic lamellar cast iron alloys with various carbon contents. The results show that the developed models can be successfully applied within the strength prediction methodology along with the simulation tools, for a wide range of carbon contents and for different solidification rates typical for both thin- and thick-walled complex-shaped iron castings.

Mathematical model of the heat interaction between the metal matrix and the reinforcement phase during the production of Metal Matrix Composites

This present paper is relevant to the establishment on mathematical model of the heat interaction between the metal matrix (liquid phase- Cu) and a reinforcement (solid- Fe) phase, during the production of the Metal Matrix Composites (MMCs) by the method of capillary molding. In this case is substituted heat object with a mathematical model drawn up and grounded to investigation of the original behavior and properties, clarifies temperature fields in bodies. The established simulation clarifies temperature fields and the causal liaison between the metal matrix and the reinforcement phase in the formation of the macro and microstructure at the time of production of MMCs. Casting process simulation is an approved method for the optimization of the methods of casting technology. The basic opportunities, ideology and structure of the software "MATLAB FEA" are introduced to simulate casting technology. The possibilities of the product are illustrated by the results obtained from a computer simulation by the technical process of the production of MMCs.

"Cast Iron - A Predictable Material” 25 Years of Modeling the Manufacture, Structures and Properties of Cast Iron

During the last 25 years, casting process simulation has developed from predicting hot spots and solidification paths to an integral assessment and optimization tool for foundries for the entire manufacturing route of castings. Modeling cast irons has always been a special challenge due to the strong interdependency between the alloy composition, applied metallurgy and metal treatment with the solidification, phases and structures which form and the resulting properties of the material.

Influence of Local Microstructure on Stresses, Durability and Fracture Mechanics of Cast Iron Components

Cast iron components show a large variety of different microstructures in dependence on chemical composition, inoculation and cooling conditions. In conventional static and dynamic calculations as well as in fracture mechanics assessment of cast iron components, the influence of local microstructure on the overall behavior of the component is not considered. Usually one material dataset is applied for the whole material. The paper describes recent developments in the field of the prediction of local microstructure and its correlation to local stress-strain, fatigue durability as well as fracture toughness. The benefit of combining casting process simulation with lifetime predictions and fracture mechanics assessment is shown for selected examples. By integrating casting process simulation, microstructure modelling, local material characterization and load analysis, a simulation based approach for predicting the behavior and performance of cast iron components already during the design stage is enabled. Thus, the local assessment helps designers to assess risks and strive for light weight designs before the casting is made.

Al-Si and Al-Si-Mg Cast Alloys Shrinkage Porosity Estimation

US A356 and US 413 cast aluminium alloys shrinkage characteristic have been discussed in the present study. Specific volume reduction leads to shrinkage in castings and it can be envisaged as a casting defect. Finite difference based casting process simulation software has been used to study the shrinkage characteristic and it is quantified using mathematical formulae. The three dimensional model of the shrinkage defect has been constructed using CAD application software. Shrinkage characteristic has also been quantified through experimental validation studies and compared well with casting process simulation. Shrinkage characteristic study and control is essential for producing defect free castings. Influence of casting shape on the shrinkage characteristic has been studied in this paper.