Effects of Heat Treatment on the Corrosion Behavior and Mechanical Properties of SiCp/Al-Mg-Si-Cu Materials

This study investigates the effects of solution and aging heat treatments on SiCp/Al-Mg-Si-Cu aluminum matrix composites using scanning electron microscopy, confocal microscopy, salt spray corrosion tests, and electrochemical characterization. Solution and aging treatments promote finely dispersed CuMgA2 phases, significantly enhancing mechanical properties, increasing hardness to 134 HV and strength to 440 MPa. With prolonged corrosion, particle stripping on the composite surface intensifies. After 8 days of corrosion, morphology fluctuation variances are 14.40 for untreated samples, 5.73 for solution-treated samples, and 4.40 for aged samples. Electrochemical tests reveal that aged samples have the lowest corrosion current (1.616×10–7 A/cm2) and the largest capacitive arc, indicating superior corrosion resistance. XPS analysis confirms that aging results in uniformly distributed CuMgAl2 phases, enhancing corrosion resistance. Aging treatment significantly improves corrosion resistance, followed by solution treatment, with untreated samples performing the worst.