Sorting Process
Industrial verification processes that classify and segregate metals based on their chemical composition and heat treatment state prevent incorrect alloys from entering critical supply chains. This activity, known as structural metal sorting, utilizes rapid electromagnetic and optical sensing instruments to verify bulk materials in real time. By measuring both electrical conductivity and magnetic permeability, the sorting equipment can distinguish between look-alike alloys.
Sensing Mechanism
A hand-held eddy current probe is pressed against the unknown component. The instrument compares the electromagnetic response against a built-in database of alloy signatures.
Calibration Routine
Instruments must be calibrated at the start of each shift using certified reference blocks representing the target alloys. When performing structural metal sorting, the operator must verify that the temperature of the reference blocks matches the temperature of the material being sorted. This thermal matching prevents measurement errors from causing false rejections.
Sorting Limitations
Surface roughness and oxide layers can interfere with the sensor coupling, which reduces measurement accuracy. To ensure reliable sorting, the metal surface must be free of grease and heavy scale. The minimum thickness of the metal must also exceed the skin depth of the electromagnetic wave to prevent thickness variations from biasing the result.
