Dresden 2011 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
MI: Fachverband Mikrosonden
MI 2: Electron Backscattering and Kossel X-Ray Diffraction
MI 2.7: Talk
Monday, March 14, 2011, 12:15–12:30, BEY 81
Investigation of intermetallic phases in multi-component Al-Si — •Asta Richter1 and Chun-Liang Chen2 — 1Technische Hochschule Wildau, Bahnhofstrasse 1, 15745 Wildau, Germany — 2Department of Materials Science and Engineering, I-Shou University, Kaohsiung 840, Taiwan
Multicomponent Al-Si alloys are important for the engineering applications such as automotive pistons. The presence of additional elements in the Al-Si alloy system allows many complex intermetallic phases to form, which are analysed by a combination of EBSD and EDX. The mechanical properties of different intermetallic phases have been investigated by using nanoindentation. In particular, the hardness and modulus of a number of phases have been established for a range of alloy compositions. In this study, the results show that both hardness and reduced modulus increase as the Ni ratio (Ni/(Ni+Cu)) of the AlCuNi phases increases (Al3Ni2 > Al7Cu4Ni > Al2Cu). The elastic modulus can be correlated with the formation temperature of the intermetallic phases. The intermetallic phases with a high heat of formation have a tight binding between atoms, and therefore their elastic modulus should be higher. The Al9FeNi phase possesses a high E/H ratio and can encourage the formation of initiation sites of cracks and debonds.