CWA 18112:2024

Aluminium And Its Alloys - Fluidity Evaluation Via Multi Strip Testing Moulds

Scope

The aim of this document is to develop a testing method to evaluate fluidity of aluminium alloys for thin wall castings in a robust and reliable way to provide useful information for subsequent use in foundry. The adopted methodology is based on strip testing, and the primary objective of this work will be focused on defining standard protocols to achieve higher repeatability for fluidity of aluminium and its alloys. The present document describes the experimental procedure proposed for the fluidity testing method.
The fluidity for the AlSi10mnMg0.2 alloy via strip testing technique through permanent mould casting is included in Annex A.
In foundry processes, the filling behaviour of die and mould cavities is controlled by the viscosity of the liquid metal/alloy employed i.e., the technological relevance is very high. However, experimental data on the viscosity of liquid metals and alloys are lacking due to the difficulty in carrying out high temperature viscosity tests. The evaluation of fluidity, intended as a technological property of metals and alloys representing the inverse of viscosity, can supply fundamental information to be used in foundry processes. This document describes the testing procedure for evaluating the fluidity with specific reference to aluminium and its alloys for thin wall casting applications by means of multi strips testing methodology. The document provides detailed guidelines for designing and experimental testing followed by data processing.
NOTE 1 The testing method described here will refer to evaluate Lf for aluminium and its alloys for various thicknesses. It is noteworthy to mention that the evaluation of fluidity (Lf) is highly dependent upon multiple variables (as discussed in clause 4), so optimization in those variables will lead to different Lf values for the same alloys. Therefore, Lf cannot not be considered as an intrinsic property of the material, but rather a material and mould based characteristic property.
NOTE 2 There are multiple studies available in the literature regarding the effect of variable factors on the fluidity of aluminium alloys. However, this document will focus on mould geometry and defining an operational standard protocol to achieve higher reproducibility of data, making this technique more reliable and easier to use in foundry.