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Cavitation causes the device to use efficiency to reduce, or even result in equipment damage, very serious consequences and impact resistance to cavitation protection is an effective way to improve parts of the service life of the material surface. And other ion beam surface metallurgy technology can be divided into the ion beam surface melting and ion beam surface cladding technique, the use of the technology can be obtained on the metal surface excellent heat resistance, wear-resistant, low-cost metallurgical layer, and in mining, metallurgy , military and other fields. The huge economic and social benefits the technology can be applied to improve the performance of the material's resistance to cavitation. Metallurgy layer cavitation destruction process analysis, to help people learn more about the mechanism of generation of cavitation, has a certain theoretical value. Strengthen the technical conditions for marine engine cast iron cylinder liner, ion beam surface melting, select the optimization of the process parameters, prepared by high-quality anti-cavitation fused hardening layer at the surface of the cylinder. Conditions for irrigation machinery, the use of ion beam surface cladding enhanced technology, ion beam surface preparation of a variety of iron-based alloy cladding layer. Optical microscopy, scanning electron microscopy, X-ray diffraction (XRD), micro hardness tester showed that the treatment by ion beam surface melting, the surface hardness of the cast iron sample, meticulous organization, the existence of the form and distribution of the graphite completely changed; to Fe, Cr, C, Ni, B, Si powder as a raw material in the cladding layer was prepared by the Q235 Steel good macro-morphology of the surface with a matrix material to achieve a metallurgical bond. Add different ingredients in this recipe based on rare-earth oxides, fine Cladding flaws, inclusions significantly reduced. But the added amount is not better, best content 0.1% La 2 O 3 0.1? 2 O . The hardness of the cladding layer substantially gradient distribution, a slight decrease of the cladding layer, the outer surface hardness than the internal subsurface has the highest hardness of the subsurface. Use of the the ultrasonic oscillation magnetostrictive instrument, analytical balance of cast iron melting layer, untreated sample and sample nitriding treatment resistance to cavitation performance. Using a scanning electron microscope to track the observed changes in the morphology of the specimen during cavitation. The results show that: the same cavitation time through the ion beam surface melting processing cast iron cylinder liner the sample cavitation weightlessness least, 12h cumulative weightlessness least. Resistance to cavitation performance untreated sample of 4.48 times better than cast iron cylinder liner specimen after nitriding treatment showed good resistance to cavitation performance. With time, the surface melting more and more obvious than without treatment and nitriding treatment resistance to cavitation performance advantages. The main reason is that surface melting occurred graphite exist completely change, and melting layer organized crime, have a certain depth. Using the same equipment, research the performance of the different iron-based alloy cladding layer sample resistance to cavitation and cavitation weight loss compared with 0Cr13Ni6Mo stainless. The results show that: the cladding layer with Fe, Cr, C, Ni, B, Si powder as a raw material having a certain degree of cavitation erosion resistance performance, is 0Cr13Ni6Mo stainless steel 0.841 times, mainly due to the hard phase grain boundaries of γ-(Fe, Ni) phase plastically deformed hinder γ-(Fe, Ni) as well as stress-induced martensite transformation toward each other. Addition of rare earth oxides, the resistance to cavitation performance improved significantly, primarily due to the addition of rare earth Cladding purify dendritic structure refinement secondary dendrite arm spacing decreases, the organization becomes uniform and compact. But the addition of rare earth should be adequate, in this experiment, to join 0.1Ce 2 O 3 the 0.1La 2 O after cladding layer cavitation performance, resistance to cavitation performance is nearly twice 0Cr13Ni6Mo stainless steel.
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