In the smelting process used krusibel kitchen . The material used is Al scrap student research results . The first thing done is the kitchen preparation process . Starting from the melting furnace cleaning and coating the coating to the placement of coal briquettes in large furnaces .

During the smelting process , the material used Al pre-heating process is carried out . It aims to eliminate the moisture on the surface of the material to avoid the formation of gas and dissolve in the molten metal which can cause gas defects . After the pre - heating the metal material is inserted into the furnace and allowed to melt . During smelting coal briquettes continuously added to maintain a stable supply of heat to melt the metal . ( Read: proses pengecoran aluminium  )

         i . alloying

In addition to the casting process which aims to produce the products according to the value dimension is also required mechanical properties suitable material . Provision of additional material ( alloying ) aims to improve the mechanical properties of the material prices . For Al granting alloying material using material Cu , Zn , Mg , P , Si , Sr , and Na .

In this lab strengthening alloying is not done . When it is done and then the sample testing ( tensile , hard ) then the resulting value is greater than without alloying .

       ii . degassing

At high temperatures the hydrogen gas will tend to diffuse into the molten metal . The hydrogen gas must be removed from the molten aluminum because it will cause defects in the casting . The process is called process gas expenses degasser . Degasser is generally used in the form of tablets or gas ( argon gas and nitrogen gas ) . Gas flushing mechanism in liquid aluminum metal are as follows :

Tablets are inserted into the molten aluminum will produce gas in the form of bubbles that almost vacuum ( < 1 atm ) . Hydrogen gas dissolved in the aluminum can not get out because the pressure inside the liquid Aluminum << 1 atm while the outside pressure of 1 atm . As a result of air bubbles produced tablets fit into hydrogen gas and air bubbles are carried upwards bersaman with other impurities dissolved in liquid aluminum . Gases or air bubbles are mostly going to be dross and will be discharged through the discharge process dross . In this lab degasser is not used .

        iii . cover Flux ( teknik pengecoran aluminium  )

Once the process is complete degasser continued with the process of flux . The process of granting flux aims to cover or covering the surface of the liquid aluminum metal to avoid the entry of hydrogen gas into aluminum metal . Provision made ​​during flux melting aluiminium start by sprinkling flux on the surface of liquid aluminum . Covering flux function for covering the surface of the molten metal in order to avoid the entry of hydrogen gas . Giving this kind of flux conducted without stirring . At the time of the flux covering practical use .

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