Evaluation and Optimization of Machinability and Surface Characteristics of Hypereutectic Al Si Cast Alloys Using Different Turning Inserts

Abstract

In the past few decades, the usage of aluminum alloys has increased rapidly from automobile sectors to consumable durables. The application varies in different sectors viz. automobile around 40%, packing 21% Building 14% Electrical 8% and consumer durables around 7%. Particularly in automobile sector the application of aluminium alloys are more due to their high strength-to-weight ratio, low density, low coefficient of thermal expansion and high wear resistance, especially in the engine components. It is also a promising alloy for replacing steel, because of its good mechanical properties and castability. The advancement in the field of application makes the study of their machining and mechanical behavior important. But the limitation of hypereutectic Aluminum Silicon(Al-Si) alloy is machining, due to the presence of hard silicon particles. The presence of coarse silicon hard particles, the machining, and surface finish are the challenges in the industries. The objective of this work is to improve the machinability and mechanical properties of the hypereutectic Aluminum- newline20%Silicon cast alloy by refining the primary silicon particles. Titanium-Boron and phosphorus were act as refiners and strontium as a modifier in the cast hypereutectic Aluminum-20%Silicon cast alloy. The Aluminum-20%Silicon cast alloy is synthesized using stir casting method with and without modifier and refiners. Refiners and modifiers were added in the form of a master alloy. After casting process, the samples were undergone machinability test with conventional lathe at room temperature and Mechanical properties (Tensile, Hardness and Impact test). The machinability test was tested with three process parameters and three different inserts. The process parameters are; Speed (500, 775 and,1200rpm), feed rate (0.1, 0.3, and 0.5 mm/rev) and depth of cut (0.5, 1.0, and 1.5mm) and three inserts are uncoated carbide insert, coated PVD (Physical Vapour deposition) insert and coated chemical vapour deposition (CVD) inserts. And along with tests, the