Damage behaviours of various coarse Al-Fe-Si particles in model wrought alloys

Al-Fe(-Si) model wrought alloys are prepared which are cast at three different cooling rates on a laboratory scale. In-situ SEM observation of tensile tests has been used to observe damage behaviours of coarse intermetallic compound (IMC) particles; Al_mFe_nSi_p and Al_mFe which are usually observed in practical wrought aluminium alloys. Particular attention is given to the chemical composition, size and aspect ratio of each broken particle. AlFeSi particles close to Al₈Fe₂Si₁ and Al₁₀Fe₃Si₃ are formed by metal mold and Graphite mold castings, respectively, and AlFeSi particles with various composition ratios are formed by furnace cooling, then being transformed into AlFe₃ by subsequent long exposure at 858 K. Almost all of the AlFeSi particles formed during the metal and Graphite mold castings remain intact, while other AlFeSi and Al_mFe particles are damaged extensively. Factors affecting the in-situ strengths of the particles are discussed.