Papers by Author: Wojciech Kasprzak

Abstract: This paper presents the prediction results of the temperature change during the solidification process of the cylinder head made of the AC2A aluminum alloy. Prediction results have been obtained by using the FDM solidification analysis based on two different solidification models were investigated. Here, the solidification model means functional relationship between the Temperature and the Fraction Solid. The first model is a simple Linear function and the second model is estimated from DSC measurement. The comparison between the simulated and measured temperatures of the aluminum cylinder head revealed that the selection of solidification models significantly reflects the prediction results. The DSC model gives higher prediction accuracy of the temperature change than the Linear model. The solidification models estimated by using Thermo- Calc and UMSA [3] were also investigated.

Abstract: Computer based classification methodology is presented in the paper for defects being developed in the Al alloys as the car engine elements are made from them produced with the vacuum casting method. Identification of defects was carried out using data acquired from digital images obtained using the X-ray defect detection methods. The developed methodology as well as the related X-ray image analysis and quality control neural networks based software were carried out to solve this problem.

Abstract: In this work effect of cooling rate on the size of the grains, SDAS, β phases and thermal characteristic results of Al-Si cast alloys have been described. The solidification process was studied using the cooling and crystallization curve at cooling rate ranging from 0,1 °Cs-1 up to 1 °Cs-1. The main observation made from this work was that when cooling rate is increased the aluminum dendrites nucleation temperature and solid fraction at the dendrite coherency point increases, which implies that mass feeding is extended. In addition to that, it was observed that solidus temperature and size of the β phases decreases when cooling rate increases. Investigations were showed, that the thermal modification could be quantitatively assessed by analysis of the crystallization curve.