Induction Hardening realizes surface hardening through rapid heating and cooling, which is characterized by high efficiency, energy saving, and small deformation, and is widely used in automotive driveshafts, crankshafts, slewing bearing of heavy machinery, wind power gears and other transmission components. Induction hardened layer depth directly affects the performance, SHD non-destructive measurement is extremely important for process adjustment, quality control, intelligent manufacturing information technology and zero-defect production, to ensure that the workpiece wear resistance and fatigue strength.