Surface Grinding Characteristics of Si₃N₄ Ceramics under High-Speed and Speed-Stroke Grinding Conditions

Multi-scale decomposition enhancement algorithm for surface defect images of Si3N4 ceramic bearing balls based on stationary wavelet transform

“…Use nonlinear transformation enhancement method to further process the approximate coefficient C(m 1 , n 1 ) after index low-pass filtering, which can be expressed as: 6) where C(m 1 , n 1 ) is the approximate coefficient after enhancement processing; α is the enhancement coefficient of defects signal, with the value range of [0,+∞]; X is the average value of the approximate coefficient; S is the standard deviation of approximate coefficient; k is the scope of enhancement, with the value range of [0,+∞].…”

“…Si 3 N 4 ceramic bearings are commonly used in optical precision instruments, high-speed machine tools, aeroengines, armoured machinery and other fields because of their excellent properties such as wear resistance, corrosion resistance, oxidation resistance, low specific gravity and high strength [1][2][3][4]. Si 3 N 4 ceramics are almost not afraid of corrosion, so Si 3 N 4 ceramic bearings can work under harsh conditions covered with corrosive media [5][6][7]. The density of ceramic balls is lower than that of the steel balls and its weight is much lighter [8].…”