Principles and Applications of shot peening:
    1 Principle: hardened steel shot the (General Applications manganese steel balls, having a diameter of 0.8-1.2mm, hardness to HRC47 50), compressed air is discharged or centrifugal shot-blasting machine flung by centrifugal force the metal surface, the use of steel the impact of the pill on the metal surface hardening the surface of the part.
    Steel shot impact metal surface: the first to make the surface of the part to generate 0.1-0.4mm deep hardened layer, automotive leaf spring to increase the parts of the surface of the plastic deformation and fracture resistance, and surface compressive stress, fatigue strength; second the defects on the surface of the part and the Since the reduced machining injury, thus reducing the stress concentration. automobile leaf spring shot peening generally work on the tensile surface, and of compression surface does not work, therefore the leaf spring peening only in the concave. processing quality should generally be the best shot peening stress (but some factories in the measure of the quality of the leaf spring peening lamina arc high change H). the shot peening diameter, material, hardness and spray speed has a direct impact on quality of shot peening.
    Applications: used in bear parts of the work under the alternating stress can greatly improve the leaf spring fatigue strength, such as automotive leaf springs, coil springs, shafts, connecting rods, shot peening can make the life expectancy has increased several times.