The research ınto the effect of Al4C3 added to the alloy of AA 2014 on the mıcrostructure and mechanıcal propertıes

At the start of the experimental study, for the process of spinn casting, the commercial aluminum ingot material is liquefied at the temperature of 750°C on the electric furnace inside a graphite crucible. Into the liquid alloy, in terms of weight, Al4C3 is added at the rates of %0,5, 1, 2 and 4 in turns. Liquid metal that involves some reinforcement is mixed by a mixer which obtains its energy from an engine, and which is prepared with Cu material. Then, die process is carried out by putting into a metal mould which is a sample of the micro tensile. The samples which are taken out of the mould are prepared for the metallography by being cut 3mm thick for each. With the infiltration method, in order to produce composite material by using stainless steel materials at the diameter of 10mm and at the height of 20mm infiltration pipes are prepared. In order to be put into the pipes, produced with the gas atomizing method AA 2014 alloy powder is mixed with Al4C3 powder which is added at the rates of %0,5, 1, 2 and 4 reinforcement volumes , in turns, in a two-dimensional. For the process of infiltration, ingot alloy AA 2014, a matrix material, is liquefied on the electric furnace at 750°C. The infiltration pipes which are tied to vacuum unit are vacuumed for 3 minutes by being immersed into the liquid metal, liquefied at the temperature of 750°C. At the viiend of the process, the materials taken out of the pipes are cut 10mm high for each. Sintering process is applied for an hour to the samples at 570°C. Aging heat treatment is performed for hours changing from 1 to 8 on the samples which are sintered after spinn casting and infiltration. Following the spinn casting method, tensile resistance of the samples exposed to aging heat treatment is investigated. In both methods, depending on the rates of the reinforcement, the effects of aging process on the hardness are examined. Energy dispersion spectroscopy (EDS) of the samples having gone under the process of heat treatment is measured and the Al4C3 dispersion is observed in the composition. By getting the image of the optical microscope and SEM of the samples, exposed to the process, microstructural properties are observed. Additionally, the positive effect of Al4C3 phase on the hardness of the material is defined. In addition to this, it has been found out that there is a huge difference between the hardness of the casting samples and the hardness of the infiltration samples. The micro hardness of casting samples is defined as 180 HV. The tensile strength of the samples which get through aging treatment following the spinn casting has been measured. The results of the tensile test have showed that the samples increase in accordance with the reinforcement amount and that the highest tensile tension reaches up to 300Mpa. Tensile % extension is observed to be at 30. Science Code : 710.1.092 Key Words : Al4C3 , Metal Matrix Komposite, Vacuum Infiltration, , Aging Page Number : 100 Adviser : Doç. Dr. Bülent BOSTAN