Fabrication of micro condenser tube through direct extrusion

In accordance with environmental regulations on refrigeration technology, the commercial A1100 alloy condenser tube that has widely been used in CFC and HCFC refrigerant systems and operated at a low working pressure (10–30 bar) was inappropriate to the eco-friendly CO2 refrigerant systems which possess a high working pressure (60–80 bar) due to the low mechanical properties. As a result, the stiffness of the conventional 1000 series alloys might not be appropriate in this requirement. The present study is mainly aimed at developing condenser tube material such as A3003 alloy for the application of eco-friendly refrigerants with higher working pressure rather than for conventional CFC and HCFC refrigerants. The mechanical properties and pressurized strength of condenser tube are greatly affected by the coarse grains, which grow during the brazing process. According to the pressurized testing, A3003 alloy is more suitable than A1100 alloy when the condenser tube is applied to eco-friendly refrigerants usage because A3003 alloy can be durable in a heat exchanger which requires high working pressure.