Linear and non-linear statistical modelling of green sand mould system

Abstract

In the present work, design of experiments (DOE) technique with response surface methodology was used to develop both linear and non-linear models, to establish the input–output relationships in green sand mould system. Grain fineness number (GFN), amount of clay, amount of water and number of strokes (degree of ramming) were considered as the input variables (parameters), which control the outputs (i.e. mould properties). Full factorial DOE was utilised for the linear model, whereas central composite design and Box-Behnken designs were used to develop the non-linear models. Experiments were conducted to measure the green sand mould properties, such as permeability, green compression strength, mould hardness and bulk density. The adequacy of all the developed models was checked through statistical analysis. Twenty random test cases were considered, to validate the models and compare their performances. A model that is statistically adequate and gives minimum percentage of deviation in prediction was adjudged as the best model for a particular response.