Thermal and Flow Analysis of Stainless Steel and Alumina Feedstock Used for 2C-PIM Process

Abstract

Within this research, rheological analysis and thermal properties of two component feedstock based on ceramic and metallic powders are carried out to understand their flow behaviour. Scanning electron microscopy (SEM), Differential Scanning Calorimeter (DSC), Thermogravimetric (TGA) and Capillary Rheometer were employed to set up optimum conditions for moulding, debinding and sintering process. DSC results defined the melting point for both backbone binder components were recorded at the same point, 55 oC. TGA results showed total weight loss of alumina and stainless steel feedstock was 17.4% and 6.43% respectively. Throughout rheological analysis, both feedstock exhibit pseudoplastic behaviour as viscosity reduce with the increase of shear rate, with shear sensitivity index less than 1. The activation energy, E for alumina and stainless steel feedstock had E values in the range of 101.93 - 2934.3 J/mol and 7132.3 - 10436 J/mol, respectively. For both alumina and stainless steel feedstock, high mouldability index occurred at the highest temperature with shear rate of 96 s-1 and 4070 s-1 which had the value of 47 x 103 and 24 x 103 respectively. The optimum injection temperature for stainless steel and alumina feedstock should be 190 °C and 230 °C respectively, since the feedstock exhibits the best characteristics for injection.

Mechanical Properties of Rice Husk-Recycled Polypropylene Composite

“…In this study, the shear sensitivity index (n) characteristics can also be evaluated. Previous studies have demonstrated that the optimal n value in the pseudoplastic flow phase is in the range of 0.5 to 0.7 [19]. The explanation is because the feedstock viscosity changes with the shear rate more quickly with a smaller n value, indicating how a high n value may lead to process instability and make it harder to control the sample quality.…”

“…The melt viscosity of recycled polymer blends was evaluated to learn more about the interaction of the polymers in the blend and how compatibilizers affect it. This study was conducted to find the feedstock's stability during the injection moulding process [19]. A feedstock's flow behaviour is preferably pseudoplastic, which means that as the shear rate increases, the viscosity drops.…”