Giant AluxX Aluminum
Giant bicycle frames use two different AluxX 6000 series alloy compounds, AluxX and AluxX SL.
AluxX is Giantâ€™s primary alloy frame building material. It is an exceptionally versatile material, exhibiting excellent weldability and corrosive resistance while maintaining relatively high tensile strength. This high tensile strength, combined with low density makes it an exceptionally lightweight frame building material.
AluxX has a nearly perfect blend of high tensile strength and high formability which allows the tubing to be finely butted (narrower wall thicknesses in non-stress areas), exhibiting superior strength and resistance to cracking.
AluxX SL is Giantâ€™s highest quality alloy frame building material; its unique compound increases the tensile strength even further over 6061 aluminum, so it can be drawn to even thinner wall thicknesses for even lighter weight.
Along with same corrosive and manufacturing advantages of AluxX, AluxX SL features an exceptionally high tensile strength-to-weight ratio. And even though tensile strength is increased, machineability and weldability are virtually unaffected, keeping additional manufacturing costs to a minimum. It is virtually immune to stress corrosion, while being easily joined by all welding and brazing methods.
ALUX SLâ€™s tensile strength is 18% greater than AluxX, which means we can use less material to build a frame, thereby cutting weight without compromising strength and durability. This is how Giant has been able to produce the lightest and stiffest aluminum road (2.3 pounds) and mountain (3.1 pounds) frames available today.
ALUMINUM MADE SIMPLE
For bicycle frame manufacturing, aluminum is combined with other materials to obtain the desired stiffness and strength. The various mixtures are called alloys and these compounds are identified by series numbers, e.g., 1000 series is the closest to pure aluminum, 2000 series is chiefly aluminum and copper, etc.
Giant concentrates on 6000 series production due to its superior fabrication, performance and testing characteristics. 6000 series aluminum consists of Al + Mg + Si (Aluminum + Magnesium + Silicon). Containing silicon and magnesium in proportions necessary to form magnesium silicide, 6000 series features good formability, weldability, machine-ability and corrosion resistance and strength, which makes it an ideal material for bicycle frames.
With the addition of traces of copper (cu), Giant is able to improve the tensile strength to very high levels while maintaining the desired welding characteristics.
Tubingâ€™s weight can be reduced by shaving the wall thickness in areas where there are less torsional forces, such as the middle of the tube. The result, called butting, is done by drawing, or extruding the tube through a die at critical points along the tube to achieve the desired wall thickness. 6000 series AluxX tubing is much easier to extrude than higher tensile strength materials as it generally exhibits a lower extrusion rate.
AluxX is a malleable material and it lends itself well to bending. However, when a tube is butted, it requires heat treatment for hardening and to achieve the necessary strength to resist torsional forces.
Giant AluxX frames all receive heat treatment, which uses a special combination of temperature and liquid curing. The frames are put into an oven and heated to a temperature of 535Â°C (1100Â°F). After removal from the oven they are quench-cooled in a liquid solution bath. This method ensures that the aluminum cools at a uniform rate, thus reducing potential flaws. After cooling, frames are realigned to exacting tolerances. The frames are then heated again to a temperature of 180Â°C (390Â°F) to complete the heat treatment process.