TY - JOUR
T1 - Study of the Al-Si-X system by different cooling rates and heat treatment
AU - Suarez, Miguel Angel
AU - Figueroa, Ignacio
AU - Cruz, Alejandro
AU - Hernandez, Alfredo
AU - Chavez, Jose Federico
PY - 2012/9
Y1 - 2012/9
N2 - The solidification behavior of the Al-12.6% Si (A1), the hypereutectic Al-20%Si (A2) and the Al-20%Si-1.5% Fe-0.5%Mn (A3) (in wt. (%)) alloys, at different cooling rates is reported and discussed. The cooling rates ranged between 0.93 °C/s and 190 °C/s when cast in sand and copper wedge-shaped molds, respectively. A spheroidization heat treatment was carried out to the alloys in the as-cast condition at 540 °C for 11 hours and quench in water with a subsequent heat treatment at 170 °C for 5 hours with the purpose of improving the mechanical properties. The samples were characterized by optical microscopy, scanning electron microscopy and mechanically by tensile test, in order to evaluate the response of the heat treatment on the different starting microstructures and mechanical properties. It was found that alloys cooled at rates greater than 10.8 °C/s had a smaller particle size and better distribution, also showed a greater response to spheroidization heat treatment of all silicon (Si) phases. The spheroidization heat treatment caused an increase in the ultimate tensile stress (UTS) and elongation when compared with the alloys in the as-cast condition. The highest UTS value of 174 MPa was obtained for the (A1) alloy.
AB - The solidification behavior of the Al-12.6% Si (A1), the hypereutectic Al-20%Si (A2) and the Al-20%Si-1.5% Fe-0.5%Mn (A3) (in wt. (%)) alloys, at different cooling rates is reported and discussed. The cooling rates ranged between 0.93 °C/s and 190 °C/s when cast in sand and copper wedge-shaped molds, respectively. A spheroidization heat treatment was carried out to the alloys in the as-cast condition at 540 °C for 11 hours and quench in water with a subsequent heat treatment at 170 °C for 5 hours with the purpose of improving the mechanical properties. The samples were characterized by optical microscopy, scanning electron microscopy and mechanically by tensile test, in order to evaluate the response of the heat treatment on the different starting microstructures and mechanical properties. It was found that alloys cooled at rates greater than 10.8 °C/s had a smaller particle size and better distribution, also showed a greater response to spheroidization heat treatment of all silicon (Si) phases. The spheroidization heat treatment caused an increase in the ultimate tensile stress (UTS) and elongation when compared with the alloys in the as-cast condition. The highest UTS value of 174 MPa was obtained for the (A1) alloy.
KW - Aluminum alloys
KW - Cooling rates
KW - Heat treatment
KW - Mechanical properties
KW - Particle size
UR - http://www.scopus.com/inward/record.url?scp=84866915077&partnerID=8YFLogxK
U2 - 10.1590/S1516-14392012005000103
DO - 10.1590/S1516-14392012005000103
M3 - Artículo
AN - SCOPUS:84866915077
SN - 1516-1439
VL - 15
SP - 763
EP - 769
JO - Materials Research
JF - Materials Research
IS - 5
ER -