Hot Gas Forming of Aluminum Alloy Tubes Using Flame Heating

Hot metal gas forming (HMGF) is a desirable way for the automotive industry to produce complex metallic parts with poor formability, such as aluminum alloys. A simple hot gas forming method was developed to form aluminum alloy tubes using flame heating. An aluminum alloy tube was heated by a flame torch while the tube was rotated and compressed using a lathe machine and simultaneously pressurized with a constant air pressure. The effects of the internal pressure and axial feeding on expansion and wall thickness distribution were examined. The results showed that the proposed gas forming method was effective for forming aluminum alloy tubes. It was also indicated that axial feeding is a vital parameter to prevent reductions in wall thickness by supplying the material flow during the forming process.

Reducing the surface defects of Ta3N5 photoanode towards enhanced photoelectrochemical water oxidation

Ta3N5 photoanodes with reduced surface defects were obtained through the nitridation of a two-step-flame-heating-derived Ta2O5 precursor and exhibited enhanced photoelectrochemical performance.

PENGARUH VARIASI CAMPURAN OKSI-ASETILEN PADA PROSES FLAME HEATING TERHADAP SIFAT FISIS DAN MEKANIK ALUMINIUM SERI 7075

<em>The optimum properties of aluminum can be achieved by the addition of alloy and heat treatment. An experimental study was conducted to investigate the effect of the oxy-acetylene mixture on the flame heating process on the physical and mechanical properties of aluminum 7075. Aluminum was heated to 480° C using an oxy-acetylene flame and then cooled rapidly. Then the results were compared with the specimen with flame heating + aging treatment. Variations of oxygen and acetylene mixtures were 0.75, 0.875 and 1 liter/min. The distance of the torch to the specimen's surface is 3 cm and the water flow rate is 1400 cc/min. The aging process is carried out with a temperature of 120°C for 3 hours + 165 for 1 hour. The results showed that the highest hardness value in flame heating treatment was 143,10 HVN with acetylene variation 0,875 liter/minute. The result of the impact test does not change much from the initial material toughness value, due to the average flame heating time that is not too long.</em>

Pengaruh Debit Air Pendingin pada Proses Flame Heating terhadap Sifat Fisis dan Mekanik Aluminium 7075

Aluminum alloy 7075 is a combination that are consists of 5,5% Zn, 2,5% Mn, 1,5% Cu, 0,3% Cr and 0,2% Mn. Heat treatment phase is using flame heating method. There are 3 steps of dissolution in flame heating process. The first is heat treatment solution in the temperature between 450-500°C. The second is quenching phase using flow speed variation 1000; 1200 and 1400 cc/minute and the third phase is using aging which to hold the room temperature until reaching 120°C. Specimen test phase using vickers hardness test, micro structure and impact test. Flame heating treatment process in 1000 cc/minute quenching cause specimen become harder, using hardness test 93,43 VHN is achieved. With additional aging treatment, the hardness increase to 152,63 VHN and almost close 153,80 VHN raw material. The biggest Impact test value is gained from the result of flame heating without aging with cooling flow variation of 1000 cc/minute is 0,630 J/mm².