What is the maximum allowable percentage of phosphorus in brazing alloys?

The maximum allowable percentage of phosphorus in brazing alloys is 0.05%. Phosphorus can negatively impact the mechanical properties of brazed joints, leading to issues such as brittleness. Maintaining a low phosphorus content ensures that the brazed joints have the necessary strength and ductility for reliable performance in HVAC systems and light commercial applications. A limit of 0.05% is established to minimize these detrimental effects, ensuring the integrity and longevity of the joints created with brazing techniques. This standard helps in adhering to industry guidelines for safety and performance in HVAC systems.

The other options represent higher percentages, which could compromise the quality of the brazed joints, making them unsuitable for the intended applications. Keeping phosphorus levels low is crucial in achieving the desired mechanical characteristics in the brazing process.