A STUDY ON MIXABILITY, MICROSTRUCTURE AND MICROPOROSITY IN LFC OF B206 ALUMINUM - COPPER ALLOY

摘要

B206 aluminum-copper alloy has a potential for wider use in the automotive industry due to its light weight and relatively superior mechanical properties as compared to aluminum-silicon alloys. The possibility of casting this alloy via Lost Foam Casting (LFC) has not been investigated in detail. Therefore, the effects of foam types (T170B-standard untreated EPS and Tl 75-brominated EPS), coating types (Styro Shield 5553 and Styro Shield 5554), copper level (4.5 wt percent and 5.0 wt percent) and titanium levels (0.5 wt percent and 0.25 wt percent) were related to fillability, microstructure and microporosity. The metal velocity in T175 EPS pattern was higher than that in T170B EPS pattern. For T175 EPS pattern, the total solidification time was 3 percent higher and the loss of temperature for decomposition of EPS was lower than those in the case of T170B EPS pattern. The grain size, porosity level and maximum pore size were quantified using Light Optical Microscopy (LOM) and image analysis. The casting with T175 EPS pattern showed larger grain size relative to that with T170B EPS pattern. The porosity level and the maximum pore size decreased significantly when the titanium level was increased from 0.05 wt percent to 0.25 wt percent.