Investigations on the mechanical and tribological behaviour of Ti 3AL 2 5V XWC composites processed by microwave sintering technique

Abstract

In this research Titanium alloy (Ti-3Al-2.5V) reinforced with newlineTungsten Carbide (WC) provides good mechanical and tribological properties newlineat room and elevated temperature condition because of its existence of newlinetungsten carbide particles. In other hand, the strength of the composites is also newlineenhanced by the presence of WC particles. In this investigation the raw newlinematerials such as Titanium (Ti), Aluminium (Al), vanadium (V) and Tungsten newlineCarbide (WC) with purity level of 99.9% was used. In this study Ti-3Al-2.5V newlinewas used a matrix material and WC is used as reinforcement with 0.5, 1.0, 1.5, newline2.0 and 2.5 wt.% by using planetary ball mill the required amount of powder newlinewas mixed with contact speed, with varying time at inert atmosphere. newlineAfter mixing the composite powders was kept in a die set newlineassembly, which is made up of tool steel, 10 mm diameter unique die set newlineassembly was fabricated for this investigation. The length to diameter ratio newlinewas maintained as 1 to get a proper compaction and thereby reduce the newlineporosity of the composite. Using Universal Testing Machine, the compaction newlinewas performed for 700 MPa at 10 sec dwell time using universal testing newlinemachine. Before compaction, the die female and male part was coated with newlinezinc stearate in acetone medium was used for lubrication and easy ejection. newlineAfter compaction all the samples was collected and sintered using Microwave newlinefurnace. Non-conventional microwave sintering was carried out at 1200°C, newline2.45 GHz. The heating rate was maintained constant for entire process newline(15 0 C / min for 1 hr.). The furnace had alumina insulation for the prevention newlineof heat loss. The heating rate was controlled by adjusting the input power. newlineBefore sintering, the green compacts were preheated at 400 °C for 0.5 h for the newlineremoval of residual additives. newline newline